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Plant identification and recommendations
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Date Posted: Wed, May 01 - 12:03 am
- I have a lot of what I am told is moss in my yard. Have pictures to send. Can you identify it and provide any treatment options?
- Thank you for reaching out to the Richmond Master Gardeners. I will send you an e-mail to be able to get the pictures from you and we will try to give you some assistance.
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Crape Myrtle Bark Scale
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Date Posted: Wed, Feb 28 - 12:46 am
- Other than digging up and destroying crape myrtles what is the next best solution for crape Myrtle scale?
- A systemic insecticide in the spring is the recommended treatment for Crape Myrtle Bark Scale (CMBS) . A soil drench of imidacloprid or dinotefuran is recommended when crape myrtles begin to leaf out in the spring, usually around April. Personally, I've had success with Bonide products and find them to be available at many local garden shops. Bonide has an annual tree and shrub product that has an active ingredient of imidacloprid. (Other insecticide recommendations from the extension office are available here: https://www.pubs.ext.vt.edu/456/456-017/456-017.html) If you decided to go with an insecticidal soap spray, just be sure to refrain from applying it when pollinators or other beneficial insects such as ladybird beetles are present on the trees. If you would really prefer to stay away from insecticides, another control option is to lightly scrub the main trunks of crape myrtles with soapy water made with mild dish detergent and a stiff-bristled brush to kill and remove CMBS. This also removes some of the sooty mold and the loose exfoliating bark that shelters CMBS, exposing the scales to any spray treatments that may be applied. And finally, its important to check and be sure your control methods are working. To assess if a control treatment was effective or not: check for live CMBS by running a fingernail over the scales and looking for a pinkish-red fluid. Dead scales will be dry, but their white bodies may persist on the trunk and branches of crape myrtle until they weather off. Good luck!!
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Crepe Myrtle Bark Scale
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Date Posted: Thu, Feb 08 - 3:03 am
- Hello! Would you be able to recommend the best product for treating a severe case of Crepe Myrtle Bark Scale? The tree is about 5 years old and has been very healthy until last year when it got the scale. I have heard that it is best to treat with a systemic insecticide in the spring but there are a lot of products out there and the prices very quite a bit. Also if there is a better way to treat than an insecticide please let me know! Also a lot of the products recommend a treatment based on the trunk size if the crepe myrtle has multiple trunks do I add all the trunks up or should I treat based on a single trunk size? Thank you so much !
- These are great questions about Crepe Myrtle Bark Scale CMBS). I had to do a little bit of research myself to figure out how to best give you some guidance. A systemic insecticide in the spring does seem to be the recommended treatment. A soil drench of imidacloprid or dinotefuran is recommended when crape myrtles begin to leaf out in the spring, usually around April. Personally, I've had success with Bonide products and find them to be available at many local garden shops. Bonide has an annual tree and shrub product that has an active ingredient of imidacloprid. (Other insecticide recommendations from the extension office are available here: https://www.pubs.ext.vt.edu/456/456-017/456-017.html) If you decided to go with an insecticidal soap spray, just be sure to refrain from applying it when pollinators or other beneficial insects such as ladybird beetles are present on the trees. Here are some guidelines for measuring the circumference of the tree trunk: 1. If it appears that a tree actually represents two or more trees that have their trunks pressing together, we measure the largest trunk. 2. If it appears that the tree tree is a single tree that splits below 4.5 feet, we measure at the narrowest point between the split and the ground. 3. If it appears that the tree tree is a single tree that splits above 4.5 feet, we measure the trunk at 4.5 feet. If you would really prefer to stay away from insecticides, another control option is to lightly scrub the main trunks of crape myrtles with soapy water made with mild dish detergent and a stiff-bristled brush to kill and remove CMBS. This also removes some of the sooty mold and the loose exfoliating bark that shelters CMBS, exposing the scales to any spray treatments that may be applied. And finally, its important to check and be sure your control methods are working. To asses if a control treatment was effective or not: check for live CMBS by running a fingernail over the scales and looking for a pinkish-red fluid. Dead scales will be dry, but their white bodies may persist on the trunk and branches of crape myrtle until they weather off.
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Browning Dwarf Arborvitae
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Date Posted: Wed, Oct 11 - 12:47 am
- Dwarf Arborvitae has brown sections, on am effort to cut them out, it appears black underneath. What is happening? Thank you.
- I'm sorry you are having these concerns with your Dwarf Arborvitae. The first thing that comes to my mind is canker. Canker is infected wounds in the branches caused by fungi. Wounds can be caused by pruning, storm damage, cold damage, or excessive wetness. In plants with canker, you will observe yellow to reddish-brown branches in the middle of healthy green branches. Closer to base of the branch you may see slightly sunken, reddish cankers with profusely exuding resin. Black pustule-like fruiting bodies known as pycnidia may be seen breaking through the bark. There is no real treatment for canker stem diseases. The fungus survives in infected bark tissues, so it is best to prune all infected branches about 3-4 inches below the canker area. Spread of the fungus can be minimized by sterilizing any blades used between all cuts with a 10 percent bleach or 70 percent alcohol solution. Try to prevent damage to trees. Stressed and wounded plants are more likely to be infested. It is best to keep dwarf trees as open as possible so that they will dry out after rain. Prune to allow air flow in plants. Clean out leaves from the insides of shrubs. Do not bury plants too deep in mulch. Prune out infected branches and fertilize affected trees if needed. Good luck!!
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Eradicating Giant Taro
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Date Posted: Wed, Aug 18 - 1:43 pm
- Continuing along the theme of invasive species, we have several clumps of elephant ears (giant taro) in our yard that we are trying to eradicate. We have dug them up twice already and they keep coming back. Any tips or solutions that can rid of us of this invasive plant? Thank you very much.
- Good morning, and thank you for your question! Giant Taro (elephant ear) are dramatic and beautiful to admire, but we know they can be problematic spreaders. This invasive plant is typically hardy only in zones 8-11, but with our recent mild winters here in zone 7, they easily thrive. They are best planted in very large pots in the garden or on the patio, where they can be contained and enjoyed without the spread. The best organic approach for removal and eradication of elephant ear in the garden is to simply dig them up (and likely repeatedly), until they are all gone. It sounds like you’ve taken this approach twice and they’ve come back. Be sure and dig wide and deep enough to remove all small pieces of the corms (tubers), and dispose of them in a plastic garbage bag. These small pieces can colonize and form new plants if left in the ground. Remove the soil in the area and replace it as well. As you’ve learned, this often requires repetition until they are all gone. If any new growth emerges during the fall, repeat the process, cutting down all growth to 1” above the ground and dig up the tubers and all small corm pieces in the ground before winter. I wish I had more magic tricks for you to try to solve this. Perhaps we’ll have a colder winter this year (more in line with our climate zone) which will help as well. Good luck!
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Shasta Daisy-browning, die back
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Date Posted: Tue, Aug 17 - 8:52 pm
- I have a large shasta daisy that I planted along my side yard years ago. About 3 years ago it started having "issues". It starts the spring with very green and abundant stems/leaves. And everything seems wonderful as the plant starts to bud....but then the flowers bloom already browning and die quickly. I am guessing it has some kind of wilt but not sure what to do. I also have dianthus in pots up my steps for the first time and it appeared that they also caught "the wilt" but they seem to be bouncing back. Not so for my Shasta daisies. Is there anything I can spray them with or can I transplant? It's such a gorgeous prolific plant.
- Sorry to hear of your daisy troubles. I'm going to refer to a previous answer I gave about Rudbeckia 'Goldsturm'. The daisies are also one of the stalwarts of the garden but can run into various problems. Please see the rudbeckia answer below. I didn't spell it out in the answer below but good drainage and air circulation are essential for plant growth and prevention of fungal diseases. And again, if your plants continue to succumb, selection of a new plant for your particular environment may be a good solution. Good luck, let us know your progress! "Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden! "
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Rudbeckia-leaves blackened
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Date Posted: Tue, Aug 17 - 8:51 pm
- I’m having a problem with my Rudbeckia Goldstrum. The leaves are blackening and the plants dry out and die. I took pictures but can’t figure out how to attach them to this message. So far the problem is only with the Rudbeckia.
- Hello there, Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden!
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Controlling Japanese Beetles
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Date Posted: Tue, Aug 17 - 8:50 pm
- How can I safely control Japanese beetles? They're devouring my roses. I don't want to use anything that would hurt bees or hummingbirds.
- Thank you for your question. I certainly understand the extent of damage Japanese beetles can cause to all parts of the Rose bush - buds, leaves, and flowers! A very safe, organic, and effective means to control Japanese beetles is a routine spray of a Neem oil solution. A Neem oil solution both kills and repels the beetles when applied every 7-10 days. This solution is totally organic and non-toxic to bees or birds. Simply mix 2 tablespoons of Neem oil per gallon of water, and spray all parts of the rose plant. A side benefit is that this Neem oil solution also controls aphids, lace bugs, mealybugs, and spider mites. Another solution is a simple soap and water solution (although not quite as effective at repelling the beetles as the Neem oil solution). Mix 4 tablespoons of dish soap with water in a spray bottle and spray all parts of the plant. Best of luck! Let us know if you have other questions!
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Mint-powdery mildew
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Date Posted: Tue, Aug 17 - 8:48 pm
- I am growing organic mint in a pot. Noticed that there is powdery white stuff on the leaves. What is that and how can I treat it naturally? Is it safe to eat / use the mint leaves if it has this white powdery stuff on it? Thanks Vilma
- The powdery white stuff you see sounds like the fungus powdery mildew. This is a very common problem with many plants but it is not difficult to correct in this type of situation. If you can, first, isolate the plant and remove affected leaves. There are many solutions. I'll list 3 here and you can see which one suits you and try another if the first choice doesn't do the trick. 1.Try using this combination-1 gallon water, 1/2 teaspoon non-detergent soap, 1 tablespoon baking soda. Pour this solution into a clean spray bottle and liberally apply this to the plant. The soap will help the diluted baking soap stick to the mint leaves and stems. It's best to water the plant well before using the solution and don't apply while the plant is in hot sun, early morning is best. You can repeat this every 7 days and after a rain. Some people feel this works best as a preventative rather than a control. So if you find that you're having the same issue with powdery mildew year after year, apply this solution at the beginning of the season. 2. Another solution is a mixture of 3 tbsp. of neem oil to one gallon of water, sprayed onto affected plants every 7-14 days. Again, don't spray while the plant is in hot sun to avoid burning. 3. And yet another possibility is using milk. I have never tried this but I understand you can get some good results. Try a mixture of 4 parts milk to six parts water and spray bi-weekly. Apply in early morning. In all cases, try any solution on a test leaf first to see how the plant responds. And no, I wouldn't eat the leaves that are covered in powdery mildew but once the plant shows no signs of the fungus, feel free to use the plant in whatever dish you like. Good luck and let us know which solution was successful for you.
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Raised beds - yellowing leaves
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Date Posted: Tue, Aug 17 - 8:41 pm
- I created new raised beds and filled them with Miracle Grow Raised Bed soil combined with mushroom compost. All of my plants have yellow leaves. The soil should be provided the necessary nutrients, and I was wondering if the weather might be part of it? Can you give me an idea of what I should do? Thank you
- Hello - interesting question. The first thing that comes to mind is your soil. It sounds like you have created a very rich soil for your new plants. Typically, yellowing leaves can indicate a nutrient deficiency, and/or the soil is too wet. As you know, mushroom compost does a good job of soaking up a lot of water and helps keep soil moist. It is also nutrient-rich, and contains a high degree of soluble salts. I’m wondering if your ratio of mushroom compost to soil is too high. The mushroom compost should make up about 1/4 of the total volume of the soil. If your soil is too concentrated and the plants are seedlings or are very young, this may result in your plants dying. The soil may actually be too rich for them. Also make sure your soil is not staying too wet. It should be allowed to dry before adding water. Good luck, and let us know if we can help further!