钓钟柳是一种比较常见的园林养殖花卉了，经常被用为绿化植物来养殖。那么，钓钟柳的花期是在什么时候呢？ [图片]钓钟柳的花期 钓钟柳的花期其实可以分为两个阶段，一个是在春季，另一个是在夏秋时。钓钟柳的花期一段是4月份——6月份，另一段是在7月份——10月份。 钓钟柳在开花的时候，通常会开成一个圆锥状的大花序，上面长有小花，呈现钟状。钓钟柳的花色还是比较丰富的，常见的有紫色、紫红色，和玫瑰红色，白色。蓝色和粉色等。 [图片]钓钟柳花期的注意事项 在钓钟柳的生长期间和它的开花前和开花后，需要注意补充养分，及时的施肥尤其是磷钾肥，可以促使其花大色艳，开得更好。在钓钟柳开花后，需要注意防寒，使其安全越冬。盆栽的钓钟柳，可以在9月份的下旬到10月份的上旬这段时间里，对其进行修剪，将整个植株的上半部分的枯枝给剪掉，然后脱盆将其埋进土里安全过冬。地栽的一般都需要将地面上的部分剪掉，并叫上防冻水进行越冬。 [图片]

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春日里有地上有一种不起眼的小花，叫#紫花地丁 ，它不择土壤，适应性极强，繁殖容易。虽然它没有玫瑰花一样的名贵，但是紫花地丁的价值分量很大。 [图片]紫花地丁花期早且集中；植株低矮，生长整齐，株丛紧密，便于经常更换和移栽布置，所以适合用于花坛或早春模纹花坛的构图。紫花地丁返青早、观赏性高、适应性强可以用种子进行繁殖，作为有适度自播能力的地被植物，可大面积群植。紫花地丁适合作为花境或与其它早春花卉构成花丛。在盆栽成株经过一定时间的冬眠后，可注意控制其开花日期，开出满盆娇嫩的花朵，用于窗台、书桌、台架等室内布置，也可制作成盆景。 有花友问编辑紫花地丁怎么种，因为紫花地丁是野花，所以花友一般有两个需求，一个是野外移栽，一个是买种子播种，所以本文我们分别从这两个方向来讲。 [图片]紫花地丁怎么种植？ 1、野外移栽 紫花地丁分部很广泛，野外可以经常看到，如果要移栽，首先要深挖，它的根系很长，尽量保持完整，挖出后立刻泡水，装入塑料袋，拿回家马上种下，注意一定要把所有花以及叶子剪掉只留叶柄和基部，然后马上浇大水，最后遮荫即可。 当然，如果有条件带土壤移植的话，可以不用剪掉叶子和花，尽量的多带土壤。 [图片]2、种子播种 我们化繁为简，一般在春季进行播种，将土壤浇透，待水渗下后，将种子撒至地面，稍加细土将种子盖严，一周即可出苗。小苗出齐要控制温度以防小苗徒长，此时光照要充足，保持土壤稍干燥。当小苗长出第一片真叶时开始分苗，移苗时根系要舒展，底水要浇透，当苗长至5片叶以上时即可定植。 紫花地丁为喜阴植物，故出苗后要勤浇水。生长强健，抵抗能力强，生长期无需特殊管理，可在其生长旺季，每隔7～10天追施一次有机肥。 到这里花友应该就了解了紫花地丁怎么种，其实紫花地丁非常好打理，粗放养护即可。 [图片]

#玉簪花 是一种观赏植物，观花或观叶价值都不低，但在养鱼过程中经常出现叶子发黄、软塌塌的现象，极大的降低了美观度。那么玉簪发黄原因有哪些，怎么解决？ [图片]玉簪花叶子软塌塌的还发黄，主要是下面这五种原因，附上详细分析，及解决措施： 土壤不适 玉簪适合种植在排水良好的土壤中，若土壤排水较差，引起积水会造成玉簪根系腐烂，致使叶片发黄变软。 解决方法：玉簪露地种植时，选用土层深厚、排水良好的沙质壤土；盆栽的最好选用疏松、肥沃的培养土。 浇水过多 栽培过程中，浇水过多，土壤排水较差时，根系在此环境下会因缺氧而腐烂，导致叶片变黄变软。 解决方法：玉簪浇水不宜过量，见干见湿，雨季期间下雨后露低栽培的玉簪要及时排水，盆栽要注意避雨。 [图片]浇水过少 玉簪喜欢潮湿的环境，不耐旱，在生长期需要更多的水分，要注意浇水。长期水分不足叶易枯黄，当环境过于干燥或受干热风吹袭也易造成叶黄。 解决方法：生长期要保持盆土湿润，空气干燥时要对着叶子喷水或向周围洒水，以保持湿度。 光照过烈 玉簪不耐强烈光照直射，特别是夏季，受到强光直射，叶片会有厚变薄，颜色变黄，生长变缓，严重的叶缘会出现枯焦的病斑。 解决方法：玉簪放在有遮阴、无日光直射处，盆栽玉簪夏季放在阴蔽度在80%以上的地方。 [图片]施肥过多 玉簪对肥料要求不高，栽植土壤施肥要足，植株开花前要多施肥，适当施一些磷酸二氢钾，促进开花。生长期若施肥过多，特别是浓肥过多，容易造成叶片发黄、脱落。 解决方法：玉簪施肥要有度，施肥要适时，根据植株的需求施肥。施肥时不要让液肥沾在枝叶上。 玉簪是观赏植物，要想它美美哒在日常的养护中还要多花点心思哦！

Emerald cedar (more properly termed "arborvitae") is a highly useful tall shrub or small tree, but homeowners and businesses who plant it frequently experience the problem of having its leaves turn brown. Insects, diseases, or even dog urine can be the sources of the problem if the leaves are turning brown in summer, as well as a more obvious potential culprit: namely, drought.[图片]Many people have asked me to address this issue. Arborvitae is widely planted in highly visible hedges and foundation plantings, where brown leaves will stick out like a sore thumb and create an eyesore. I was finally inspired to write an article about the problem by a reader who emailed me the following question: I planted over 40 Emerald Cedars along the border between my property and my neighbour as a privacy fence, as well as a sound barrier for my dogs barking. I planted the trees at least 5 years ago, and just last summer I noticed that they are all turning brown, instead of having that lovely fresh green colour they used to. Can you tell me what the problem is and what you might suggest as a remedy to save my Emerald cedar trees?[图片]Location of Brown Foliage Determines Whether You Have a True Problem When you see brown leaves on the inner part of Emerald cedars, that is generally not a problem: it is normal to see brown leaves in this area in fall or spring, as that foliage is just getting old and the Emerald cedars are shedding it. But leaves turning brown at the outer tips of branches can be a serious problem. If you see such brown leaves in the summer, it could be due to any of the following (or some combination thereof): Your Emerald cedars could be infested with aphids (in which case you would have to spray). Inspect foliage closely for masses of these tiny, soft-bodied insects. They could be infested with spider mites (in which case you would have to spray). Look closely for tiny webs. Your Emerald cedars could be succumbing to fungal diseases. Look for tiny black spots in summer. If you see them, remove infected branches to prevent further spread. If the problem persists, have your local garden center recommend an antifungal spray.[图片]During a hot, dry summer, plants often fail to receive sufficient water. To address reason #4 above, as a preventive measure, you can supply artificial irrigation and bark mulch. For established plants, a deep soaking every other week is sometimes recommended. Of course, this does not address the issue of vegetation that has already been damaged by drought. In severe cases, root damage can occur, resulting in dead plants. How do you check to see if your plant is dead or still alive? Slice off a bit of bark with a knife, so that you can "look under the hood," so to speak. If you see green, the plant is probably still alive (on a partially dead plant, it may take you a few tries before you find green somewhere). If all that you find is brown, the plant is most likely dead, and you should start making plans to remove it and replace it.[图片]Is Your Yard Going to the Dogs? Although this does not apply to the reader mentioned above (because it is unlikely to account for browning on 40 Emerald cedar trees all at once), it could apply to someone with a small number of Emerald cedars: if the foliage has been sprayed with dog urine, that can cause brown leaves. This is just one of many examples of the challenges we face in landscaping with dogs. If there is a stray dog problem in your area, you can deter dogs with dog repellents.[图片]Note also that, in diagnosing and solving this problem of Emerald cedar leaves turning brown, it is important to specify the time of year. The above assumes the problem developed during the summer. I have a separate FAQ dealing with brown leaves on arborvitae (Emerald cedars) in winter.

Orchids have a love/hate relationship with fungi. Many people know that orchids developed their amazing flowers to attract very specific pollinators in the wild, but fewer people are aware of the plant's relationship to various fungus. After pollination, an orchid plant produces a large seed pod. This seed pod is filled with thousands or even tens of thousands of tiny seeds. In general, plants have two strategies with seeds: they either produce very few large seeds that are loaded with food and nutrients to help the seed germinate, or they produce many smaller seeds but invest less in each seed.[图片]Orchids are definitely among the latter group: their seeds tend to be tiny, vulnerable little packets of cells that can't even properly germinate on their own. After an orchid seed is released from its seed pod, it floats on the wind until it lands in a suitable location. Once there, the seed must be colonized by a specific kind of fungus. The colonized orchid seed destroys and digests the fungal, drawing enough energy from it to begin germination. So it's fair to say that orchids would not exist without fungus.[图片]Common Fungi In cultivation, however, various fungi extract a terrifying revenge: they are among the most common killers of orchids. Orchids are susceptible to some fungi, including Pythium, Phytophthora, Rhizoctonia, Fusarium, Anthracnose, Botrytis, and Cercospora, among others. These fungal agents attack various parts of the plant, including roots, stems, leaves, and flowers. Destructive by themselves, fungal attacks also leave the plant vulnerable to opportunistic infection by bacteria.[图片]Why Is Fungi an Issue? Part of the reason fungi is such a problem in orchids is because they naturally thrive under the same conditions that many people assume orchids like wet, humid, and still. This, however, is something of a misconception. Most orchids we grow are canopy plants, not swamp plants. They rely on good air circulation and drying periods to stay healthy. So the first and best defense against fungal attacks is cultural: don't let your plants stay wet, never head into a night with wet plants, and provide plenty of strong airflows to keep your plants healthy.[图片]That said, however, most orchid growers will deal with some fungal infection at some point, especially the annoying black leaf spots that disfigure our perfect plants. In most cases, these infections can be successfully treated by spraying early with an effective anti-fungal agent.

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Yellowing leaves on a phalaenopsis are not necessarily a cause for alarm. It's normal and natural for older leaves to yellow and gradually drop off. Older phalaenopsis often have somewhat elongated stems where old leaves have dropped away. On healthy plants, new roots will continuously emerge from the stem, eventually forming a mass of roots.[图片]However, if the leaves are yellowing from the top of the plant, there is a problem. If the leaves are still plump and firm, the plant is most likely receiving too much light and it's washing out the color. If the leaves are wrinkled and listless, the plant is most likely dehydrated.[图片]Yellow Leaves If the leaves on your Phalaenopsis orchid are yellow, it could be an indication that something is wrong. There are a number of factors that can cause the leaves of an orchid to become discolored, including direct sunlight, low temperatures, and root rot. Once any yellowing is discovered, it is time to figure out if there is a problem with the plant. If you discover the yellowing leaf is located on the bottom of the plant, don’t worry. This is a natural process of the plant to discard the mature leaf in order to produce a new leaf. However, if multiple leaves are turning yellow or top leaves are yellow, your plant may be sick.[图片]3 Reasons Why Your Phalaenopsis Leaves Are Yellow The first step is to isolate the plant away from any other orchids that you may have to ensure that they do not become ill as well. Here are 3 steps to take to try to determine the problem: Direct sun may be the culprit. The leaves of a Phalaenopsis orchid can burn and turn yellow if they are exposed to direct sunlight. Try putting your orchid in a place that receives sufficient indirect sunlight.[图片]Is the temperature right? Overly low temperatures can also cause orchid leaves to turn yellow. Make sure the temperatures around your orchid are between 65 and 80 degrees Fahrenheit during the day and 60 and 70 degrees at night. Check the roots. Overwatering can lead to root rot, which can in turn cause its leaves to turn yellow. You should only water the plant when the top one inch of the potting medium is dry and the roots are white, and make sure there are enough holes in the pot to allow proper drainage. If your orchid is suffering from root rot but you see your plant still has some healthy green roots, trim the rotted roots and repot the plant in new media. Mist the leaves the first week in place of watering.[图片]A Tip to Prevent Overwatering Overwatering is one of the most common problems and one of the most serious Here's a hint to make sure that in your quest to keep your orchid happy, healthy and beautiful that you don't overwater. To avoid overwatering, we recommend watering your Phalaenopsis orchid with three ice cubes once a week so that the roots will soak up water slowly.

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"Dog vomit fungus" is one of those oddities of nature that just makes you say "eww eww." Even if you've never had it in your garden before, it's pretty safe to say that you'll know it when you have it; its nickname couldn't be more precise.[图片]The fungus, which has the scientific name Fuligo septicai, is also sometimes called "scrambled egg fungus." It is most likely to show up during warm, wet periods, sometimes seeming to pop up out of nowhere overnight. It often grows in wood mulches or along the sides of untreated wood, and sometimes in lawn grass.[图片]Their less-than-attractive appearance may cause concern that they're harming garden plants, but they are actually really interesting (if you have kids, they'll get a kick out of learning more about this disgusting fungus.) Slime molds, such as Fuligo septicai, are saprophytic, which means that they feed on decaying organic materials. They are not diseases, and won't really harm your plants. Occasionally, they'll grow on plants that are growing in mulch, and if a large enough colony forms, they may smother the plant. This is uncommon, however, and you'll usually just find the mold in the mulch itself. Dog vomit fungus, like other slime molds, are most often found in moist, shady areas, where they thrive. Crevices, mulch, rotting logs, leaf litter and along untreated lumber are all very common places to find it.[图片]Description of Dog Vomit Fungus Its name is fairly accurate. If you've had a dog, you'll know it when you see it. It is also known as "scrambled egg fungus," because the fruiting bodies (the part you see) is light yellowish in color and looks a bit like scrambled egg curds. It usually appears in small clumps, clinging to mulch, the bases of rotting tree trunks, or other wooden objects.[图片]Life Cycle of Dog Mold Fungus Slime molds like the dog mold fungus produce spores that are wind-borne. They are very resistant and can survive even during hot, dry weather. The spores can remain viable for several years, waiting for conditions to be right. When warm, moist conditions are present, those dormant spores absorb moisture and crack open to release a swarm sphere, and shortly after, gardeners will see that tell-tale, disgusting looking fungus appear.[图片]Controlling Dog Vomit Fungus As mentioned above, generally dog vomit fungus poses no threat to plants. It's really just an unattractive nuisance. The best way to control it is to break it up and dry it out. Dog vomit fungus growing in mulch or leaf litter can simply be raked out and disposed of (probably not in your compost, unless you either practice hot composting or want more of it to show up in your garden later.) Dog vomit fungus growing along lumber or tree stumps can be scraped away with a trowel or small shovel and disposed of. If you have it growing in your lawn or in plants, gently rake it out as best you can and get rid of it. A strong jet of water will also dislodge any of the remaining fungi still clinging to the plants (though it may pop up again later.)[图片]If dog vomit fungus continues to be a problem, you may want to consider switching from wood-based mulches to something else, such as gravel. In general, it doesn't pop up often enough to be a real issue. So, if you see this unattractive fungus in your garden, don't panic. Its primary crime is being unpleasant to look at. Leave it (if it doesn't bother you too much), or scrape it up and get rid of it, and hope for drier conditions in the future so you won't have to see it again anytime soon.

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Does Milk Control Powdery Mildew? You can do everything right in your garden and there will still be problems - like powdery mildew. Some things are beyond our control. When weather conditions are right, a host of fungal diseases will move in. Keeping your plants healthy and giving them plenty of air circulation will help them withstand many problems, but not all. Sometimes you need the help of a fungicide.[图片]However, that does not necessarily mean you need to use chemicals. What is Powdery Mildew? Powdery mildew refers to a group of diseases that all show up as a powdery white coating on leaves, stems, and sometimes even flowers. It does not usually kill plants, but it can weaken them and diminish photosynthesis, leading to poor yield and plants that don't last the season. It is spread by spores that are carried by the wind or splashed onto leaves. Powdery mildew favors humid, rather than wet conditions. The spores form when the humidity is high and disperse when the humidity diminishes. Spores can over-winter on plants or plant debris and start the process all over again. End of season garden clean-up and planting disease resistant varieties are your best powdery mildew controls.[图片]Although powdery mildew affects many plants, there are several species of powdery mildew fungus and they each have their preferred hosts. So powdery mildew on zinnias will not move to lilacs or cucumbers. No matter what plant has powdery mildew, this is a fast spreading problem and you need to take action quickly. However you don't need to reach for the big guns. There are a handful of relatively low toxic remedies and most can be homemade.[图片]A baking soda solution is one and the following milk solution is another. Using Milk as a Fungicide Milk has become the latest secret weapon in fighting powdery mildew. Actually it's not so secret and it's been used in treating diseases for decades. It's been tried as an additive to improve the spreading and sticking of other pesticides and Dr. Linda Chalker-Scott, of Washington State University, cites many studies where milk was tested against the transmission of tobacco mosaic and other viruses. - to mixed reviews. Most recently, milk has been getting a lot of good press as an anti-fungal spray, specifically against powdery mildew on cucumbers and squash.[图片]How to Use Milk to Control Powdery Mildew The dilution used by home gardeners is: 1 part milk to 2 - 3 parts water. The solution is then sprayed on the plant's leaves every 10-14 days. It works best as a preventative, rather than a cure, which makes it hard to determine whether it actually works since you don't know if your plants would have gotten it anyway.[图片]How does Milk Work as a Fungicide? For the past several years, researchers have been experimenting with spraying a diluted solution of regular milk on a variety of plants, mostly cucurbits (squash and cucumbers). They have been seeing enough success to continue experimenting. Home gardeners are now getting in on the research, but very often a control group is missing, so their results are not definitive.[图片]As to exactly how milk works against the fungus, no one is certain. It appears that the proteins in milk offer an antiseptic-like effect, when exposed to sunlight. To be effective, the solution should be applied in bright sun. Soak both sides of the leaves until the solution is dripping. If you've ever left milk out in heat or direct sun, you know that the odor of spoiled milk is not pleasant, but it does dissipate somewhat quickly. The protein is in the milk fat, and both whole and skim milk have been tried by home gardeners. In fact, researchers used whey, a milk by-product, because it was cheaper.[图片]You can try your own experiments with whatever you have on hand. To really test it, spray the solution on only some plants and leave others untreated. Author and horticulture professor Dr. Jeff Gillman has also recommended using the milk solution for black spot on roses. There hasn't been a lot of institutional research on this, but home remedies are not profitable and often get short shrift in research. Interestingly, Dr. Gillman also recommends simply spraying plants prone to mildew with water. Since powdery mildew doesn't like getting wet, spraying the plants daily seems to help thwart it.[图片]Sources: Clemson University Extension Jeff Gillman Jeff Gillman on Gotta Garden Science News The Myth of Milk and Roses, Linda Chalker-Scott, Ph.D.

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What is Powdery Mildew? Powdery mildew is one of the most commonly occurring plants problems. It is a fungal disease that affects plant leaves and stems, coating them in what looks like a white or gray powder-like substance. Although any plant can get powdery mildew, some are very susceptible, crab apples, cucumbers and all types of squash, lilacs, phlox and roses. In severe cases, powdery mildew can even spread to the buds, flowers, and fruits of plants. The white coating greatly diminishes the appearance of the plant, but it is not fatal unless left uncontrolled. However, as it spreads, it stresses and weakens the plant and makes it hard for photosynthesis to occur. It's wise to treat it as soon as you see symptoms, or maybe even before.[图片]Controlling Powdery Mildew with Baking Soda Baking soda has long been used as an inexpensive control for powdery mildew on plants. Unfortunately baking soda fungicide is mostly effective as a preventative, offering only minimal benefits after your plants have become infected. If you know which plants are susceptible, spraying them weekly with the baking soda recipes, during humid or damp weather, can greatly reduce the incidence of powdery mildew in your garden.[图片]To control powdery mildew on plants, mix together: 1 tablespoon of baking soda ½ teaspoon of liquid soap 1 gallon of water Do not store unused mixture.[图片]While this recipe has been known to be effective, it can burn the leaves of some plants. It is recommended that you water your infected plants well a couple of days before applying this mixture, and don’t apply it in full sun. Try on a small area first, to test the plant’s response before spraying the entire plant. Some recipes also recommend applying 1 tablespoon of ultralight horticultural oil to the mixture. The oil coats and smothers the fungi. The soap is added to help the mix spread and cling to the leaf surface. Be sure to apply to lower leaf surfaces as well.[图片]Control versus Cure Unfortunately, this baking soda mixture works best as a preventative, applied before powdery mildew has a chance to spread on your plant. It is less effective as a cure, once the fungus has taken hold. If you know a plant is affected by powdery mildew year after year, as is the case with many monarda, pholx, and lilacs, they spraying early in the season may prevent any occurrence of powdery mildew that year. It is still worth trying after signs of powdery mildew appear, but it might not get rid of all the fungus.[图片]Another Homemade Powdery Mildew Option Spraying plants with a milk mixture, after they have been infected with powdery mildew, is showing a lot of promise for actually killing the fungus. Read more about how to use milk to control powdery mildew.[图片]There May be More Uses for This Baking Soda Recipe Researchers are still studying the effects of using a baking soda mixture on other fungal diseases such as: black spot, rust and anthracnose.

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Why does magnolia foliage get black spots on it? Have you ever had the leaves on such a tree turn brown and then fall off? Then you will find the following exchange between the author and a reader interesting -- and, hopefully, helpful. The reader reported buying two magnolia trees and bringing them home, only to discover that the leaves had black spots all over them. So he returned to the garden center, scrutinized the rest of the crop, and learned that all of the other magnolias that this business had for sale displayed the same black spots. [图片]When confronted, their response was: Moisture is to blame. Back home, the leaves eventually turned brown and fell off. The reader wondered, "What type of disease is this?" Here was the response to the reader; this information may be able to help many of you out there who have similar problems: Since Leaf Spot Is a Fungus, It Thrives in Moist Conditions Your problem sounds like a case of leaf spot. Since it is usually caused by a fungus, "moisture" (which was cited as the culprit at the store) is, indeed, likely to blame. Fungi thrive in moist conditions. As the University of Connecticut (UConn) Extension remarks, in the presence of the fungal spores, all it takes is "a film of water" on the leaf for the spores to germinate and penetrate the leaf. It is at that point that foliage becomes diseased. [图片]The actual spots of "leaf spot" are not always black, by the way. They are commonly brown, as well. But do not assume that, just because the color of the spot is not dark, the disease is not leaf spot: The color can be tan, too or even red. Most experts do not regard leaf spot as something to worry over very much when it occurs on a mature specimen in this genus, be it a star magnolia tree, saucer magnolia, etc. Their advice typically is to remove the diseased brown leaves that have dropped and then dispose of them properly. The idea is to prevent the fungus from spreading. [图片]But, as the UConn Extension also notes, leaf spot can be a serious disease for trees under stress, which includes newly-planted trees (as in your case). Already weakened by the stress, young magnolia trees infested with leaf spot can die from the infestation. It is in these situations that chemical control is warranted. Seek a copper-based fungicide to battle the leaf spot. Problem is, as the same source observes, you have to spray the fungicide on at the right time in order for it to do its job. When is the right time? Well, you must understand that the fungicide works as a protectant, not as a cure. This means, unhappily, that the right application time is before the fungus attacks a leaf. [图片]Do you see the challenge implicit in this treatment? You must be vigilant enough to detect the leaf spot when it first attacks your magnolia tree. If you catch it and spray before too much foliage has been infected, you may be able to halt its advance. Otherwise, treatment is unlikely to be effective. Preventive Control Measures You Can Take In terms of prevention (for future reference), healthy magnolia trees tend to resist leaf spot. [图片]So care for your magnolia properly to keep your specimen in tip-top condition and, thereby, more resistant to this disease. Since moisture promotes the spread of fungus, it is a good idea to enhance air circulation. This can be achieved by: Pruning off branches on the magnolia trees that are rubbing against each other. Pruning off branches of any surrounding trees or shrubs that may be invading the magnolias' space. [图片]The Fungi (and One Bacterium) That May Be the Culprits Above, it was noted that the leaf-spot disease is caused by fungi. But precisely which fungi? And can anything else cause it? According to the Pacific Northwest Plant Disease Management Handbook, a bacterium can also be the culprit: namely, Pseudomonas syringae pv. syringae. The same source lists the following as the main fungi responsible for the problem: Cladosporium spp. Coniothyrium spp. Phyllosticta magnoliae Septoria spp.

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