文章
Miss Chen
2017年08月10日
All roses, even the beautiful and hardy Knock Out, can sometimes have problems. While most of these issues will not kill the plant, they can cause leaf spots, yellowing, wilting and blight that may make it look like the rose is dying.
Pests and Disease
Black spot disease and mildew can still cause problems for Knock Out roses. In addition, pests like aphids, sawfly larvae and spider mites will often feed on Knock Outs. If left unchecked, these diseases and pests can weaken the plant and make it susceptible to disease and extremes of cold and heat.
Hydration
Roses do not like to have wet feet but still need adequate water. A good rule of thumb is to water 1 inch per week, 2 inches in arid climates or drought conditions. Mulch around the base of the rose to hold moisture.
Pruning
Knock Out roses should be pruned hard in the spring. Remove all crossing tips and branches, and thin the rose to provide adequate airflow.
Hardiness Zone Issues
Knock Out roses are considered to be hardy through U.S. Department of Agriculture Zone 5, but if you live in an area close to the dividing line between two zones, your roses may not tolerate harsher weather. Consider replacing your Knock Out with a rose more suited for your location.
Pests and Disease
Black spot disease and mildew can still cause problems for Knock Out roses. In addition, pests like aphids, sawfly larvae and spider mites will often feed on Knock Outs. If left unchecked, these diseases and pests can weaken the plant and make it susceptible to disease and extremes of cold and heat.
Hydration
Roses do not like to have wet feet but still need adequate water. A good rule of thumb is to water 1 inch per week, 2 inches in arid climates or drought conditions. Mulch around the base of the rose to hold moisture.
Pruning
Knock Out roses should be pruned hard in the spring. Remove all crossing tips and branches, and thin the rose to provide adequate airflow.
Hardiness Zone Issues
Knock Out roses are considered to be hardy through U.S. Department of Agriculture Zone 5, but if you live in an area close to the dividing line between two zones, your roses may not tolerate harsher weather. Consider replacing your Knock Out with a rose more suited for your location.
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文章
Miss Chen
2017年08月09日
Agaves (Agave spp.) are drought-tolerant succulents that have long, sword-shaped leaves that open in a rosette form. While some agaves feature smooth sides, many species have hardened, needle-like tips and curled, hardened teeth along the leaf edges. Agaves with sharp spines should be kept a minimum of 6 feet away from walking areas in the yard because the spines can easily puncture skin and cause serious injury. If you have small children or pets, removing the spines is the safest option. The spines won't grow back and cutting the spines won't kill the plant.
Step 1
Wear heavy protective clothing and eyewear, such as long-sleeved shirt, gloves, pants and safety glasses or goggles to prevent skin and eye contact with the agave plant spines and sap. While the sap of some agaves is consumed, some plant saps can cause irritation upon contact.
Step 2
Cut straight across the hardened leaf tips just above the point where the fleshy leaves transition to hardened spines, using a pair of bypass pruners. Cut just above the thick, fleshy portion of the leaves, but do not cut through this flesh because this can attract pests such as the agave snout weevil that lay their eggs in damaged sections of the plant. The weevil larvae burrow into the soft tissue of the plant, introducing a harmful bacteria that rots the plant cells, decomposing the plant from the inside out.
Step 3
Cut the curled, spiny teeth from the margins of the agave plant leaves, using bypass pruners or a pair of fingernail clippers. Clip off the sharp point, leaving a dull, flat surface at each spine. Do not cut into the fleshy portion of the leaf. Start from the spines closest to the leaf tip and work your way down to the base.
Step 4
Cut the straight, pointed spines from the tips and the curled spines from the leaf margins as new leaves emerge from the terminal bud in the center of the plant. The outermost leaves of an agave are the oldest leaves; new leaves grow straight up from the center and fan out into the rosette to make room for the next series of new leaves.
Step 1
Wear heavy protective clothing and eyewear, such as long-sleeved shirt, gloves, pants and safety glasses or goggles to prevent skin and eye contact with the agave plant spines and sap. While the sap of some agaves is consumed, some plant saps can cause irritation upon contact.
Step 2
Cut straight across the hardened leaf tips just above the point where the fleshy leaves transition to hardened spines, using a pair of bypass pruners. Cut just above the thick, fleshy portion of the leaves, but do not cut through this flesh because this can attract pests such as the agave snout weevil that lay their eggs in damaged sections of the plant. The weevil larvae burrow into the soft tissue of the plant, introducing a harmful bacteria that rots the plant cells, decomposing the plant from the inside out.
Step 3
Cut the curled, spiny teeth from the margins of the agave plant leaves, using bypass pruners or a pair of fingernail clippers. Clip off the sharp point, leaving a dull, flat surface at each spine. Do not cut into the fleshy portion of the leaf. Start from the spines closest to the leaf tip and work your way down to the base.
Step 4
Cut the straight, pointed spines from the tips and the curled spines from the leaf margins as new leaves emerge from the terminal bud in the center of the plant. The outermost leaves of an agave are the oldest leaves; new leaves grow straight up from the center and fan out into the rosette to make room for the next series of new leaves.
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成长记
Lucky Coyote
2017年08月09日
My Vera is doing exceptionally well, where I pruned it a few days ago, there are some starts forming at the leaf removal spots ❤
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文章
Dummer. ゛☀
2017年08月09日
Honeywort, a member of the family Boraginceae, is mainly found on the coast; it is a curious-looking plant with a leaf and flower stem which gradually uncurls. The flowers shown above are creamy-yellow, but there is also a deep purple form, shown below. Both colour forms are found in Portugal.
Identification
Typically 2o to 40cm in heightbut occasionally growing to 70cm, Honeywort in an annual and produces tubular flowers typically 22mm long and 6mm in diameter. Young flowers have a sweet scent.
Leaves of Cerinthe major are alternate, spatulate (spoon shaped) and stalkless.
Habitat
Generally favouring river valleys and other depressions that provide a degree of water retention, Honeywort is also seen on some dry roadside verges.
Distribution
This plant is common and widespread throughout the Mediterranean region and parts of North Africa, and its range extends eastwards at least as far as Turkey.
Taxonomy
Cerinthe comes from the greek Keros, meaning wax, and anthos, meaning flower. The implication is that bees were thought to take wax from these flowers. The specific epithet major means greaer; it refers to the large size of the flowers compared with those of other Cerinthe species.
Identification
Typically 2o to 40cm in heightbut occasionally growing to 70cm, Honeywort in an annual and produces tubular flowers typically 22mm long and 6mm in diameter. Young flowers have a sweet scent.
Leaves of Cerinthe major are alternate, spatulate (spoon shaped) and stalkless.
Habitat
Generally favouring river valleys and other depressions that provide a degree of water retention, Honeywort is also seen on some dry roadside verges.
Distribution
This plant is common and widespread throughout the Mediterranean region and parts of North Africa, and its range extends eastwards at least as far as Turkey.
Taxonomy
Cerinthe comes from the greek Keros, meaning wax, and anthos, meaning flower. The implication is that bees were thought to take wax from these flowers. The specific epithet major means greaer; it refers to the large size of the flowers compared with those of other Cerinthe species.
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文章
Dummer. ゛☀
2017年08月09日
These aquatic plants are difficult to identify to species level because the leaf shape varies with water depth andflow rate. Some starworts are annuals and others are perennials.
Distribution
Common Water Starwort is illustrated here. In Wales, where this specimen was photographed, the River Teifi around Lampeter has several other startwort species including Callitriche hamulata, Intermediate Water Starwort.
Callitriche stagnalis is widespread also throughout the rest of Britain and Ireland and occurs as a native plant in most parts of mainland Europe and in northern Africa. In North America Common Starwort is an introduced species, first discovered in the New York area in 1861, and is now a nuisance invasive weed in parts of the USA and Canada..
Habitat and Blooming Times
Starworts of various kinds occur mainly in shallow (depth to about a metre) static and slow- to moderately-fast-flowing water.
The green flowers of Callitriche stagnalis, which are minute, appear at the bases of the leaves from May to August, and tiny, four-segmented fruits follow. It is mainly by examination of the shape of the fruits, which in the case of Common Starwort are nearly round. (Without their fruits, the various Callitriche species are very difficult to separate.)
Etymology
Callitriche, the genus name, comes from the Greek words From the Greek kalli- meaning beautiful, and -thrix which means hair. Callitriche is therefore a reference to the hair-like stems of starwort plants.
The specific epithet stagnalis is, as you might expect, a habitat reference: this species often occurs in stagnant (standing or stationary) water, although it is also probably the most common of the starworts that grow in slow-flowing streams and ditches in Britain and Ireland.
Distribution
Common Water Starwort is illustrated here. In Wales, where this specimen was photographed, the River Teifi around Lampeter has several other startwort species including Callitriche hamulata, Intermediate Water Starwort.
Callitriche stagnalis is widespread also throughout the rest of Britain and Ireland and occurs as a native plant in most parts of mainland Europe and in northern Africa. In North America Common Starwort is an introduced species, first discovered in the New York area in 1861, and is now a nuisance invasive weed in parts of the USA and Canada..
Habitat and Blooming Times
Starworts of various kinds occur mainly in shallow (depth to about a metre) static and slow- to moderately-fast-flowing water.
The green flowers of Callitriche stagnalis, which are minute, appear at the bases of the leaves from May to August, and tiny, four-segmented fruits follow. It is mainly by examination of the shape of the fruits, which in the case of Common Starwort are nearly round. (Without their fruits, the various Callitriche species are very difficult to separate.)
Etymology
Callitriche, the genus name, comes from the Greek words From the Greek kalli- meaning beautiful, and -thrix which means hair. Callitriche is therefore a reference to the hair-like stems of starwort plants.
The specific epithet stagnalis is, as you might expect, a habitat reference: this species often occurs in stagnant (standing or stationary) water, although it is also probably the most common of the starworts that grow in slow-flowing streams and ditches in Britain and Ireland.
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文章
Dummer. ゛☀
2017年08月09日
Family - Scrophulariaceae
Stems - To +2m tall at anthesis, from stout taproot, herbaceous, densely stellate pubescent, winged by decurrent leaf tissue, erect, sometimes branching at inflorescence.
Leaves - First years leaves in a basal rosette to +1m in diameter but typically less. Blades entire to crenate to crenate-dentate, to 75cm long, 15cm broad, oblong to narrowly obovate, tapering at base, rounded or subacute at apex, dense stellate pubescent (soft to the touch), with prominent veins below. Margins often undulate. Cauline leaves becoming oblanceolate, sessile, reduced upwards, with tissue decurrent and undulate.
Inflorescence - Indeterminate dense terminal spike to 1m tall (long). Foliaceous to scalelike bracts subtending flowers. Bracts equaling or longer than calyx, dense stellate pubescent.
Flowers - Corolla yellow, zygomorphic, 5-lobed, +/-2.5cm broad. Corolla tube to +/-8mm long. Lobes rounded, stellate pubescent externally, glabrous internally. Stamens 5(3+2), alternating with corolla lobes, adnate on basal half of corolla tube, the upper 3 shorter than the lower 2. Filaments yellow, to 1.1cm long, villous mostly in upper half (hairs fewer and secund on lower two stamens). Anthers orange, 2mm long. Style green, mostly glabrous but with some hairs at base, -1cm long. Stigma capitate. Ovary superior, stellate pubescent to tomentose, 2-locular. Placentation axile. Ovules many. Calyx accrescent, 5-lobed, dense stellate pubescent. Tube to 2mm long. Lobes 5-6mm long, 2-3mm broad at base, lance-acuminate. Capsule to 1cm long, broadly ovoid, stellate pubescent, many-seeded, with persistent style.
Flowering - May - September.
Habitat - Pastures, fields, waste ground, disturbed sites, roadsides, railroads.
Origin - Native to Europe.
Other info. - This common plant was one of the first, if not the first, introduced plants from Europe to North America. In Carravaggio's painting "Saint John the Baptist", (painted ~1604AD), V. thapsus is painted at the feet of John the Baptist. Incidentally, this painting is displayed in Kansas City at the Nelson Atkins Museum of Art.
V. thapsus is unmistakable in the field. The fuzzy leaves and long flowering spikes can't be missed. The plant is common throughout Missouri.
Traditionally V. thapsus has been used to cure headaches, fevers, cramps, burns, and a host of other ailments (including cold feet). The plant does contain coumarins and other toxins so it should be used wisely.
Stems - To +2m tall at anthesis, from stout taproot, herbaceous, densely stellate pubescent, winged by decurrent leaf tissue, erect, sometimes branching at inflorescence.
Leaves - First years leaves in a basal rosette to +1m in diameter but typically less. Blades entire to crenate to crenate-dentate, to 75cm long, 15cm broad, oblong to narrowly obovate, tapering at base, rounded or subacute at apex, dense stellate pubescent (soft to the touch), with prominent veins below. Margins often undulate. Cauline leaves becoming oblanceolate, sessile, reduced upwards, with tissue decurrent and undulate.
Inflorescence - Indeterminate dense terminal spike to 1m tall (long). Foliaceous to scalelike bracts subtending flowers. Bracts equaling or longer than calyx, dense stellate pubescent.
Flowers - Corolla yellow, zygomorphic, 5-lobed, +/-2.5cm broad. Corolla tube to +/-8mm long. Lobes rounded, stellate pubescent externally, glabrous internally. Stamens 5(3+2), alternating with corolla lobes, adnate on basal half of corolla tube, the upper 3 shorter than the lower 2. Filaments yellow, to 1.1cm long, villous mostly in upper half (hairs fewer and secund on lower two stamens). Anthers orange, 2mm long. Style green, mostly glabrous but with some hairs at base, -1cm long. Stigma capitate. Ovary superior, stellate pubescent to tomentose, 2-locular. Placentation axile. Ovules many. Calyx accrescent, 5-lobed, dense stellate pubescent. Tube to 2mm long. Lobes 5-6mm long, 2-3mm broad at base, lance-acuminate. Capsule to 1cm long, broadly ovoid, stellate pubescent, many-seeded, with persistent style.
Flowering - May - September.
Habitat - Pastures, fields, waste ground, disturbed sites, roadsides, railroads.
Origin - Native to Europe.
Other info. - This common plant was one of the first, if not the first, introduced plants from Europe to North America. In Carravaggio's painting "Saint John the Baptist", (painted ~1604AD), V. thapsus is painted at the feet of John the Baptist. Incidentally, this painting is displayed in Kansas City at the Nelson Atkins Museum of Art.
V. thapsus is unmistakable in the field. The fuzzy leaves and long flowering spikes can't be missed. The plant is common throughout Missouri.
Traditionally V. thapsus has been used to cure headaches, fevers, cramps, burns, and a host of other ailments (including cold feet). The plant does contain coumarins and other toxins so it should be used wisely.
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文章
Miss Chen
2017年08月08日
Aloe vera soothes burns and skin irritations and works as a moisturizer for dry skin. To get the most benefit from your plant, harvest all of the gel from a leaf at one time, and then refrigerate it and use as needed.
Storing Leaves
You can wrap whole leaves in plastic wrap or store them in sealable plastic bags and then refrigerate them for several days. Whole aloe vera leaves may also be wrapped and then frozen.
Storing Gel
Stand your aloe leaf cut side down in a glass for 15 minutes to allow the sap to drain naturally. Discard the sap. Place the leaf on a cutting board and cut your aloe leaf in half horizontally. Scoop out the gel with a spoon. Place the sap in a jar, seal the jar and store it in the refrigerator, using it as you need it.
Considerations
The gel will naturally turn brown over time. To prevent discoloration, cut a vitamin E gel capsule in half and squish the vitamin into the gel. Stir the substances together. If you're storing a whole leaf, the plant will wither and mold, so use it within a week.
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文章
Miss Chen
2017年08月08日
Jade plants (Crassula ovata) can be grown from a single leaf and end up over 5 feet tall. They have fleshy branches and rounded, glossy leaves. As succulents, they require little water but grow best in bright light with some direct sunshine. Jade plants lose older leaves naturally but an increase in the rate of leaf loss is often the first sign of a problem.
Underwatering
Jade plants that are not receiving enough water often shed their older leaves. If the lower leaves on your plant are shriveling up and then falling off, check its soil. If it is completely dry, water your plant thoroughly. Water a jade plant every time the top inch of its soil is completely dry. Jade plants add leaves and shoots during the summer and need more water during the hot summer months.
Overwatering
Succulent jade plants are vulnerable to rot and must never be left with their pot standing in water. Check your plant's soil if its leaves turn yellow and start to drop off. Do not apply any more water until it has dried out completely. Remove the plant from its pot if you notice any soft sections on the trunk or branches. Wash all the soil off the roots and place it on a windowsill for a week. Cut off any branches or roots that are soft and repot in cactus potting mix.
Light
If your jade is losing its lower leaves at the beginning of winter this is likely to be because of low light. Move your plant closer to a window to increase light levels. Jade plants that are kept close to a window will shed leaves if they touch the glass on very hot or very cold days. Keep the plant a few inches back from the glass.
Temperature
Keep jade plants above 50 degrees Fahrenheit during the winter as cold temperatures will damage the leaves. Frost will kill your jade plant completely. Jade plants will shed leaves if they are placed in a cold draft or close to a radiator. A sudden change in temperature caused by a move will also cause leaf drop. The leaves will grow back once your plant has adapted to its new surroundings.
Leaf Shine
Never use leaf shine products on jade plants as it will cause all their leaves to turn yellow and fall off. Household chemicals and cleaners have a similar effect if they touch the leaves. Jade plant leaves shine naturally if they are dust free and the plant is healthy.
Pests
Jade plants are vulnerable to infestations of mealy bugs and scale insect. Mealies and scale make jade leaves sticky and can encourage the growth of molds. They also cause leaf drop and deformed leaves. Treat mealies and scale by dabbing them with a paintbrush dipped in a 70 percent solution of rubbing alcohol.
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文章
Dummer. ゛☀
2017年08月08日
You may know it as leaf, shoot or twig blight. It affects a variety of shrubs, trees and other plants. Combating anthracnose can be a frustrating process, leaving gardeners asking, “How do you treat anthracnose effectively?” Knowing more about what plants get anthracnose and how to prevent it can go a long way in successful anthracnose control. 
Anthracnose Disease Info
Anthracnose is a fungal disease that tends to attack plants in the spring when the weather is cool and wet, primarily on leaves and twigs. The fungi overwinter in dead twigs and fallen leaves. Cool, rainy weather creates perfect conditions for the spores to spread. Dry and hot weather stop the progression of the disease that may begin again once the weather conditions become optimal. The problem can be cyclic but is rarely fatal. Anthracnose fungus infects many deciduous and evergreen trees and shrubs, as well as fruits, vegetables and grass. Anthracnose is noticeable along the leaves and the veins as small lesions. These dark, sunken lesions may also be found on stems, flowers and fruits. In order to distinguish between anthracnose and other leaf spot diseases, you should carefully examine the undersides of leaves for a number of small tan to brown dots, about the size of a pin head. If you are unsure about diagnosing anthracnose, consult your local Cooperative Extension office for assistance and additional anthracnose disease info.
What Plants Get Anthracnose?
A wide variety of plants can be affected by anthracnose fungus, including those grown outside of a greenhouse, such as woody ornamentals and tropical foliage plants. Potted plants and greenhouse crops such as cyclamen, ficus, lupine, palms, succulents and yuccas are sometimes affected. Trees and shrubs that are prone to anthracnose include maple, camellia, walnut, ash, azalea, oak and sycamore.
How Do You Treat Anthracnose?
Anthracnose control begins with practicing good sanitation. Picking up and disposing of all diseased plant parts, including twigs and leaves, from the ground or from around the plant is important. This keeps the fungus from overwintering near the plant. Proper pruning techniques to rid trees and plants of old and dead wood also helps with prevention of anthracnose fungus. Keeping plants healthy by providing proper light, water and fertilizer will strengthen the plant’s ability to ward off a fungus attack. Stressed trees and plants have a difficult time recovering from anthracnose fungus. Chemical treatment is rarely used except when the disease involves newly transplanted plants or continual defoliation.
Anthracnose Disease Info
Anthracnose is a fungal disease that tends to attack plants in the spring when the weather is cool and wet, primarily on leaves and twigs. The fungi overwinter in dead twigs and fallen leaves. Cool, rainy weather creates perfect conditions for the spores to spread. Dry and hot weather stop the progression of the disease that may begin again once the weather conditions become optimal. The problem can be cyclic but is rarely fatal. Anthracnose fungus infects many deciduous and evergreen trees and shrubs, as well as fruits, vegetables and grass. Anthracnose is noticeable along the leaves and the veins as small lesions. These dark, sunken lesions may also be found on stems, flowers and fruits. In order to distinguish between anthracnose and other leaf spot diseases, you should carefully examine the undersides of leaves for a number of small tan to brown dots, about the size of a pin head. If you are unsure about diagnosing anthracnose, consult your local Cooperative Extension office for assistance and additional anthracnose disease info.
What Plants Get Anthracnose?
A wide variety of plants can be affected by anthracnose fungus, including those grown outside of a greenhouse, such as woody ornamentals and tropical foliage plants. Potted plants and greenhouse crops such as cyclamen, ficus, lupine, palms, succulents and yuccas are sometimes affected. Trees and shrubs that are prone to anthracnose include maple, camellia, walnut, ash, azalea, oak and sycamore.
How Do You Treat Anthracnose?
Anthracnose control begins with practicing good sanitation. Picking up and disposing of all diseased plant parts, including twigs and leaves, from the ground or from around the plant is important. This keeps the fungus from overwintering near the plant. Proper pruning techniques to rid trees and plants of old and dead wood also helps with prevention of anthracnose fungus. Keeping plants healthy by providing proper light, water and fertilizer will strengthen the plant’s ability to ward off a fungus attack. Stressed trees and plants have a difficult time recovering from anthracnose fungus. Chemical treatment is rarely used except when the disease involves newly transplanted plants or continual defoliation.
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文章
Dummer. ゛☀
2017年08月08日
Many ornamental and edible plants display dark, necrotic looking spots on their leaves. This is a symptom of bacterial leaf spot disease. Bacterial leaf spot on plants will discolor, and in extreme cases, kill leaves. Tiny, microscopic single celled organisms are what causes bacterial leaf spot. There are several methods on how to treat bacterial leaf spot and save your plant’s glorious leaves. Early identification is crucial to effective management of bacterial leaf spot disease. Symptoms of Bacterial Leaf Spot Bacterial leaf spot on plants may manifest in several different ways. Symptoms of bacterial leaf spot may include black edged lesions, brown spots with yellow halos or just light and dark areas on the foliage. Spots are irregular and measure between 3/16 and ½ inch wide. They can occur on the top or bottom of a leaf and kill sections of the tissue when they cluster together.
Symptoms of bacterial leaf spot may also appear on the edges of a leaf, where it appears brownish yellow and the tissue dries and breaks off. The leaves become quite papery and delicate when the bacterial disease attacks leaf edges. The disease is most prevalent on older leaves but will quickly establish on newer tissue. What Causes Bacterial Leaf Spot? Organisms that cannot be seen with the naked eye are the cause of this visibly damaging plant disease. Wet, cool conditions promote the formation of these bacteria, which can spread on plants quickly. The bacteria splash onto leaves or overwinter on plant debris in soil. Bacteria divide to reproduce and one bacterium can multiply quickly in just a matter of hours. Bacteria reproduce the fastest when temperatures are 77-86 F. (25-30 C.). High rates of infection will cause leaf loss and can seriously compromise a plants health. This makes the disease extremely contagious and bacterial leaf spot disease treatment extremely important.
The pathogen is also carried in infected seed; however, there are some disease resistant seed strains for food crops. Additionally, choose disease free transplants, rotate crops and avoid overhead watering to prevent spreading the bacteria. How to Treat Bacterial Leaf Spot In addition to the previous tips on preventing spread of the disease, you can use a copper fungicide on crops. This has limited management use unless it is applied early in the disease cycle. On ornamental plants, remove the affected leaves at the first sign to prevent the bacteria from jumping onto adjacent leaves. Some of the most common hosts are lettuce, beets, eggplant, peppers and large leaved ornamental plants, such as philodendrons.
Remove old vegetable debris in the garden and do not plant new crops where host plants were once growing. There are no recognized chemical treatments for bacterial leaf spot disease. Your best bet is prevention and mechanical control at the first sign of symptoms of bacterial leaf spot.
Symptoms of bacterial leaf spot may also appear on the edges of a leaf, where it appears brownish yellow and the tissue dries and breaks off. The leaves become quite papery and delicate when the bacterial disease attacks leaf edges. The disease is most prevalent on older leaves but will quickly establish on newer tissue. What Causes Bacterial Leaf Spot? Organisms that cannot be seen with the naked eye are the cause of this visibly damaging plant disease. Wet, cool conditions promote the formation of these bacteria, which can spread on plants quickly. The bacteria splash onto leaves or overwinter on plant debris in soil. Bacteria divide to reproduce and one bacterium can multiply quickly in just a matter of hours. Bacteria reproduce the fastest when temperatures are 77-86 F. (25-30 C.). High rates of infection will cause leaf loss and can seriously compromise a plants health. This makes the disease extremely contagious and bacterial leaf spot disease treatment extremely important.
The pathogen is also carried in infected seed; however, there are some disease resistant seed strains for food crops. Additionally, choose disease free transplants, rotate crops and avoid overhead watering to prevent spreading the bacteria. How to Treat Bacterial Leaf Spot In addition to the previous tips on preventing spread of the disease, you can use a copper fungicide on crops. This has limited management use unless it is applied early in the disease cycle. On ornamental plants, remove the affected leaves at the first sign to prevent the bacteria from jumping onto adjacent leaves. Some of the most common hosts are lettuce, beets, eggplant, peppers and large leaved ornamental plants, such as philodendrons.
Remove old vegetable debris in the garden and do not plant new crops where host plants were once growing. There are no recognized chemical treatments for bacterial leaf spot disease. Your best bet is prevention and mechanical control at the first sign of symptoms of bacterial leaf spot.
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文章
Dummer. ゛☀
2017年08月08日
If you’ve noticed an outbreak of leaf mottling along with blistering or leaf curl in the garden, then you may have plants affected by TMV. Tobacco mosaic damage is caused by a virus and is prevalent in a variety of plants. So exactly what is tobacco mosaic virus? Keep reading to find out more, as well as how to treat tobacco mosaic virus once it’s found. What is Tobacco Mosaic Virus? Although tobacco mosaic virus (TMV) is named for the first plant in which it was discovered (tobacco) back in the 1800s, it infects over 150 different types of plants.
Among plants affected by TMV are vegetables, weeds and flowers. Tomato, pepper and many ornamental plants are struck annually with TMV. The virus does not produce spores but spreads mechanically, entering plants via wounds. History of Tobacco Mosaic Two scientists made the discovery of the first virus, the Tobacco Mosaic Virus, in the late 1800’s. Although it was known to be a damaging infectious disease, tobacco mosaic was not identified as a virus until 1930. Tobacco Mosaic Damage Tobacco mosaic virus does not usually kill the plant that is infected; it does cause damage to flowers, leaves and fruit and stunts a plant’s growth, however. With tobacco mosaic damage, leaves may appear mottled with dark green and yellow-blistered areas. The virus also causes leaves to curl. Symptoms tend to vary in severity and type depending on the light conditions, moisture, nutrients and temperature. Touching the infected plant and handling a healthy plant that may have a tear or nick, whereby the virus can enter, will spread the virus.
Pollen from an infected plant can also spread the virus, and seeds from a diseased plant can bring the virus to a new area. Insects that chew on plant parts may carry the disease as well. How to Treat Tobacco Mosaic Disease There has not yet been found a chemical treatment that effectively protects plants from TMV. In fact, the virus has been known to survive for up to 50 years in dried plant parts. The best control of the virus is prevention. Reducing and eliminating sources of the virus and the spread of insects can keep the virus kept under control. Sanitation is the key to success.
Garden tools should be kept sterilized. Any small plants that appear to have the virus should be removed immediately from the garden. All plant debris, dead and diseased, should be removed as well to prevent the spread of the disease. In addition, it is always best to avoid smoking while working in the garden, as tobacco products can be infected and this can spread from gardener’s hands to plants. Crop rotation is also an effective way to protect plants from TMV. Virus-free plants should be purchased to help avoid bringing the disease into the garden.
Among plants affected by TMV are vegetables, weeds and flowers. Tomato, pepper and many ornamental plants are struck annually with TMV. The virus does not produce spores but spreads mechanically, entering plants via wounds. History of Tobacco Mosaic Two scientists made the discovery of the first virus, the Tobacco Mosaic Virus, in the late 1800’s. Although it was known to be a damaging infectious disease, tobacco mosaic was not identified as a virus until 1930. Tobacco Mosaic Damage Tobacco mosaic virus does not usually kill the plant that is infected; it does cause damage to flowers, leaves and fruit and stunts a plant’s growth, however. With tobacco mosaic damage, leaves may appear mottled with dark green and yellow-blistered areas. The virus also causes leaves to curl. Symptoms tend to vary in severity and type depending on the light conditions, moisture, nutrients and temperature. Touching the infected plant and handling a healthy plant that may have a tear or nick, whereby the virus can enter, will spread the virus.
Pollen from an infected plant can also spread the virus, and seeds from a diseased plant can bring the virus to a new area. Insects that chew on plant parts may carry the disease as well. How to Treat Tobacco Mosaic Disease There has not yet been found a chemical treatment that effectively protects plants from TMV. In fact, the virus has been known to survive for up to 50 years in dried plant parts. The best control of the virus is prevention. Reducing and eliminating sources of the virus and the spread of insects can keep the virus kept under control. Sanitation is the key to success.
Garden tools should be kept sterilized. Any small plants that appear to have the virus should be removed immediately from the garden. All plant debris, dead and diseased, should be removed as well to prevent the spread of the disease. In addition, it is always best to avoid smoking while working in the garden, as tobacco products can be infected and this can spread from gardener’s hands to plants. Crop rotation is also an effective way to protect plants from TMV. Virus-free plants should be purchased to help avoid bringing the disease into the garden.
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Dummer. ゛☀
2017年08月08日
Alternaria leaf spot in the garden is a real problem for growers of brassicas, but it also makes life miserable for tomato and potato growers, causing plaque-like spots on leaves and fruits. Treating alternaria can be difficult, so many gardeners do what they can to prevent this fungus from getting a toe-hold in their plots. Let’s learn more on what is alternaria and how to treat this gardener’s nightmare. What is Alternaria? The fungal pathogens in the genus Alternaria can be devastating to plants year after year.
The spores overwinter on old plant debris and attach themselves to seeds, making alternaria leaf spot especially tricky to completely eliminate if you save your own seeds. Garden vegetables are common targets of these wind-blown spores, but alternaria is not discriminatory in the plants it attacks — apples, citrus, ornamentals and weeds have been known to develop leaf spots caused by this fungus. Alternaria symptoms once infection begins include small, dark, circular spots that regularly reach ½ inch in diameter. As they spread, alternaria leaf spots may change in color from black to tan or gray, with a yellow halo around the outside. Because spot development is heavily influenced by the environment, there are frequently noticeable concentric rings that spread from the initial point of infection. Sporulation causes these spots to develop a fuzzy texture. Some plants tolerate alternaria spots better than others, but as these spots increase on tissues, leaves may wilt or drop, leading to sunburned crops or weak plants. Fruits and vegetable surfaces can be infected with alternaria spots as well, the lesions making them unsightly and unmarketable.
Because alternaria can invade tissues invisibly, eating spot-covered produce is not recommended. How to Treat Alternaria Treatment for alternaria requires fungicide to be sprayed directly on infected plants, as well as improvements in sanitation and crop rotation to prevent future outbreaks. Organic gardeners are limited to sprays of captan or copper fungicides, making control much more challenging. Conventional gardeners can use chlorothanil, fludioxinil, imazalil, iprodine, maneb, mancozeb or thiram on plants listed on the label of their chemical of choice, but should still strive for prevention in areas with known alternaria pathogens. Mulch can help to slow the spread of alternaria spores already in the soil when applied immediately after planting. Experiments at the New York State Agricultural Experiment Station showed that mulched kale crops experienced fewer and less severe problems with alternaria leaf spot than the control plants, with straw mulches significantly more successful at suppression than black plastic or biodegradable plastic mulches. The straw-mulched plants also grew much taller than other plants in the experiment.
Crop rotation is vital to preventing alternaria fungal spores from germinating – although the many alternaria fungal diseases look similar, the fungi themselves are often very specialized in the type of plant they will attack; gardens on four year rotations can avoid alternaria building in the soil. Cleaning up fallen leaves and spent plants as soon as possible will also limit the number of spores in the soil. Healthy, well-spaced plants tend to suffer less severe damage from alternaria than their overly-stressed kin.
The spores overwinter on old plant debris and attach themselves to seeds, making alternaria leaf spot especially tricky to completely eliminate if you save your own seeds. Garden vegetables are common targets of these wind-blown spores, but alternaria is not discriminatory in the plants it attacks — apples, citrus, ornamentals and weeds have been known to develop leaf spots caused by this fungus. Alternaria symptoms once infection begins include small, dark, circular spots that regularly reach ½ inch in diameter. As they spread, alternaria leaf spots may change in color from black to tan or gray, with a yellow halo around the outside. Because spot development is heavily influenced by the environment, there are frequently noticeable concentric rings that spread from the initial point of infection. Sporulation causes these spots to develop a fuzzy texture. Some plants tolerate alternaria spots better than others, but as these spots increase on tissues, leaves may wilt or drop, leading to sunburned crops or weak plants. Fruits and vegetable surfaces can be infected with alternaria spots as well, the lesions making them unsightly and unmarketable.
Because alternaria can invade tissues invisibly, eating spot-covered produce is not recommended. How to Treat Alternaria Treatment for alternaria requires fungicide to be sprayed directly on infected plants, as well as improvements in sanitation and crop rotation to prevent future outbreaks. Organic gardeners are limited to sprays of captan or copper fungicides, making control much more challenging. Conventional gardeners can use chlorothanil, fludioxinil, imazalil, iprodine, maneb, mancozeb or thiram on plants listed on the label of their chemical of choice, but should still strive for prevention in areas with known alternaria pathogens. Mulch can help to slow the spread of alternaria spores already in the soil when applied immediately after planting. Experiments at the New York State Agricultural Experiment Station showed that mulched kale crops experienced fewer and less severe problems with alternaria leaf spot than the control plants, with straw mulches significantly more successful at suppression than black plastic or biodegradable plastic mulches. The straw-mulched plants also grew much taller than other plants in the experiment.
Crop rotation is vital to preventing alternaria fungal spores from germinating – although the many alternaria fungal diseases look similar, the fungi themselves are often very specialized in the type of plant they will attack; gardens on four year rotations can avoid alternaria building in the soil. Cleaning up fallen leaves and spent plants as soon as possible will also limit the number of spores in the soil. Healthy, well-spaced plants tend to suffer less severe damage from alternaria than their overly-stressed kin.
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Dummer. ゛☀
2017年08月08日
It can be difficult to differentiate between leaf-related problems that occur in the summer garden, but angular leaf spot disease is pretty distinctive, making it easy for new gardeners to diagnose successfully. Plants that develop very regular leaf spots that follow veins may be suffering from this disease. Read on to find out more. What is Angular Leaf Spot? Angular leaf spot in plants is caused by several bacteria that survive in seeds and plant debris, including Pseudomonas syringae and Xanthomonas fragariae. These bacteria are somewhat host-specific, with P.
syringae targeting cucurbits and X. fragariae attacking strawberries. Symptoms first appear as small, water-soaked spots on leaves, but spread rapidly when conditions are moist and ambient temperatures are between 75 and 82 F. (24-28 C.). Spots expand until they fill the entire area between leaf veins, but do not cross over, which creates a tiled appearance on larger leaves. Older spots may dry out and tear, leaving holes behind. On fruits, angular leaf spot disease manifests as perfectly circular, water-soaked spots, much smaller than those on the leaves. As the disease progresses, the spots take on a chalky white appearance and may crack open, allowing pathogens to contaminate fruits and cause fruit rot.
How to Treat Angular Leaf Spot Treating angular leaf spot is not a simple, straightforward task. Once a plant is infected, it cannot be cured easily and most gardeners will remove the plant from their garden to prevent further spreading of the disease. Future problems can be prevented by only using certified, disease-free seed, practicing a three-year crop rotation with different plant families and making a habit out of cleaning up plant debris as it falls to the ground.
Beds with poor drainage or that are over-watered favor angular leaf spot — pay close attention to your watering habits if this disease has already developed in your plants. Before watering, check the soil moisture level with your hand. Unless the top 1 to 2 inches of soil feel dry to the touch, do not water; and when you do, make sure to water at the base of plants. Good watering practices can reduce the risk of many diseases, including angular leaf spots in plants.
syringae targeting cucurbits and X. fragariae attacking strawberries. Symptoms first appear as small, water-soaked spots on leaves, but spread rapidly when conditions are moist and ambient temperatures are between 75 and 82 F. (24-28 C.). Spots expand until they fill the entire area between leaf veins, but do not cross over, which creates a tiled appearance on larger leaves. Older spots may dry out and tear, leaving holes behind. On fruits, angular leaf spot disease manifests as perfectly circular, water-soaked spots, much smaller than those on the leaves. As the disease progresses, the spots take on a chalky white appearance and may crack open, allowing pathogens to contaminate fruits and cause fruit rot.
How to Treat Angular Leaf Spot Treating angular leaf spot is not a simple, straightforward task. Once a plant is infected, it cannot be cured easily and most gardeners will remove the plant from their garden to prevent further spreading of the disease. Future problems can be prevented by only using certified, disease-free seed, practicing a three-year crop rotation with different plant families and making a habit out of cleaning up plant debris as it falls to the ground.
Beds with poor drainage or that are over-watered favor angular leaf spot — pay close attention to your watering habits if this disease has already developed in your plants. Before watering, check the soil moisture level with your hand. Unless the top 1 to 2 inches of soil feel dry to the touch, do not water; and when you do, make sure to water at the base of plants. Good watering practices can reduce the risk of many diseases, including angular leaf spots in plants.
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文章
Dummer. ゛☀
2017年08月08日
You can tell a lot about your plant’s health from its leaves. When they’re green, shiny and flexible, all systems are go; that plant is happy and care-free. But when plants develop brown leaves in the middle of their canopy or leaf browning in center of leaves, problems are afoot. Most of the time, these symptoms can be traced back to improper growing conditions, but they may also be caused by fungi and viruses.
Causes for Plants Going Brown in Center Crown and Root Rot The center rotting out of a plant is almost always related to crown or root rot. Most plants can’t tolerate a soggy environment, especially those with crowns densely covered with leaves, like African violets. When you keep the soil wet all the time, fungal pathogens take advantage of the humidity that develops under the leaves of these low-growing plants, reproducing rapidly. Both root and crown rot can appear similar in these short plants, with the plants going brown in the center as the disease progresses. If you’re asking yourself, “What is causing brown leaves in center of my plant,” you need to check the soil moisture first. Allow the top inch or two of soil to dry between waterings and never leave plants soaking in water-filled saucers. Plants with root rot may be saved if you catch it in an early stage. Dig your plant, trim out any brown, black or soggy roots and replant into a well-draining medium — chemicals won’t help, the only thing that will fix root rot is a drier environment.
Diseases That Cause Brown Leaves Other reasons why leaves turn brown in middle include fungal diseases like anthracnose and host-specific rusts. They often start along the mid-vein of leaves, either near the center or toward the stem end. Fungal diseases are aggravated or initiated by humid conditions. Rusts can be treated early in the disease process, but good sanitation is vital to prevent it from spreading further. When tiny, rust-colored spots appear in the middle of your plant’s leaves, try neem oil before breaking out stronger chemicals like thiophanate methyl, myclobutanil or chlorothalonil. Remove any plants that resist treatment and keep all plant debris cleaned up off of the ground. Anthracnose also begins along the mid-vein in many plants, but is primarily a problem for woody plants, although tomatoes and other crops have been known to contract it. This fungus creates water-soaked lesions on leaves along the mid-vein that soon dry out and brown. Anthracnose is difficult to treat, but crop rotation and sanitation are the keys to preventing reinfection. A number of plant viruses result in vein necrosis, the death of the central leaf vein and those tissues surrounding it, causing browning. Other common symptoms include discolored spots, rings or bullseyes in a range of colors, general unthriftiness and distortion of emerging growth.
A plant affected by a virus cannot be cured, so it’s best to destroy them before other plants are infected as well. Many viruses are vectored by small, sap-sucking insects; be on the lookout for pests in and around sick plants.
Causes for Plants Going Brown in Center Crown and Root Rot The center rotting out of a plant is almost always related to crown or root rot. Most plants can’t tolerate a soggy environment, especially those with crowns densely covered with leaves, like African violets. When you keep the soil wet all the time, fungal pathogens take advantage of the humidity that develops under the leaves of these low-growing plants, reproducing rapidly. Both root and crown rot can appear similar in these short plants, with the plants going brown in the center as the disease progresses. If you’re asking yourself, “What is causing brown leaves in center of my plant,” you need to check the soil moisture first. Allow the top inch or two of soil to dry between waterings and never leave plants soaking in water-filled saucers. Plants with root rot may be saved if you catch it in an early stage. Dig your plant, trim out any brown, black or soggy roots and replant into a well-draining medium — chemicals won’t help, the only thing that will fix root rot is a drier environment.
Diseases That Cause Brown Leaves Other reasons why leaves turn brown in middle include fungal diseases like anthracnose and host-specific rusts. They often start along the mid-vein of leaves, either near the center or toward the stem end. Fungal diseases are aggravated or initiated by humid conditions. Rusts can be treated early in the disease process, but good sanitation is vital to prevent it from spreading further. When tiny, rust-colored spots appear in the middle of your plant’s leaves, try neem oil before breaking out stronger chemicals like thiophanate methyl, myclobutanil or chlorothalonil. Remove any plants that resist treatment and keep all plant debris cleaned up off of the ground. Anthracnose also begins along the mid-vein in many plants, but is primarily a problem for woody plants, although tomatoes and other crops have been known to contract it. This fungus creates water-soaked lesions on leaves along the mid-vein that soon dry out and brown. Anthracnose is difficult to treat, but crop rotation and sanitation are the keys to preventing reinfection. A number of plant viruses result in vein necrosis, the death of the central leaf vein and those tissues surrounding it, causing browning. Other common symptoms include discolored spots, rings or bullseyes in a range of colors, general unthriftiness and distortion of emerging growth.
A plant affected by a virus cannot be cured, so it’s best to destroy them before other plants are infected as well. Many viruses are vectored by small, sap-sucking insects; be on the lookout for pests in and around sick plants.
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文章
Dummer. ゛☀
2017年08月07日
What is volutella blight on plants? Also known as leaf and stem blight, volutella blight is a destructive disease that affects pachysandra plants and boxwood shrubs. Early diagnosis and vigilant plant care are the keys to volutella blight control. Read on to learn about treating volutella blight. Volutella Blight Symptoms Initial symptoms, which appear in early spring, frequently resemble winter injury. Volutella blight symptoms begin with delayed emergence of new growth and patches of wilted, discolored, yellow, red or bronze leaves that gradually increase in size before turning black and falling from the plant.
Greenish-brown, water-soaked cankers girdle the stems, causing the plant to shrivel and wilt as the cankers turn dark black or brown. Pinkish fungal spores often appear during humid weather. Volutella Blight Treatment Prune damaged growth.
Wipe cutting tools with bleach solution or rubbing alcohol between each cut to prevent spread of disease. Shake or rake the plant to remove infected leaves, then destroy the debris. Although fungicide sprays won’t cure volutella blight, application of lime sulfur or copper sprays may help in case of severe infestations. Spray plants just before growth appears in spring, and then continue throughout the growing season as directed on the label. Plants may benefit from an additional volutella blight treatment in autumn to protect late summer growth. Remove plants if the blight is overly severe.
Replace them with more disease-resistant shrubs or ground covers. Volutella Blight Control and Prevention To prevent volutella blight, keep plants healthy and minimize stress with regular trimming, which improves air circulation and increases penetration of sunlight. Trim plants during dry weather. Water plants in the morning so the foliage has plenty of time to dry before temperatures drop later in the day, as volutella blight is more prevalent in wet, humid conditions. Avoid heavy mulch, which may keep the growing environment overly damp. Treat insect infestations as they appear, and clean beds and rake plant debris in autumn.
Greenish-brown, water-soaked cankers girdle the stems, causing the plant to shrivel and wilt as the cankers turn dark black or brown. Pinkish fungal spores often appear during humid weather. Volutella Blight Treatment Prune damaged growth.
Wipe cutting tools with bleach solution or rubbing alcohol between each cut to prevent spread of disease. Shake or rake the plant to remove infected leaves, then destroy the debris. Although fungicide sprays won’t cure volutella blight, application of lime sulfur or copper sprays may help in case of severe infestations. Spray plants just before growth appears in spring, and then continue throughout the growing season as directed on the label. Plants may benefit from an additional volutella blight treatment in autumn to protect late summer growth. Remove plants if the blight is overly severe.
Replace them with more disease-resistant shrubs or ground covers. Volutella Blight Control and Prevention To prevent volutella blight, keep plants healthy and minimize stress with regular trimming, which improves air circulation and increases penetration of sunlight. Trim plants during dry weather. Water plants in the morning so the foliage has plenty of time to dry before temperatures drop later in the day, as volutella blight is more prevalent in wet, humid conditions. Avoid heavy mulch, which may keep the growing environment overly damp. Treat insect infestations as they appear, and clean beds and rake plant debris in autumn.
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