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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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Planting under Magnolia tree
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Date Posted: Tue, Aug 17 - 8:49 pm
- Hi! I have a huge magnolia tree in my backyard that constantly drops leaves all over. I don’t rake very often because it takes hours and the ground just gets covered up again in a few days. I have two questions for you. The first is, should I be raking? By that I mean is there any benefit to doing so (besides aesthetic) and/or any harm in not doing it? My second question is what should I plant under the areas that are constantly covered by leaves? The few occasions I have raked, I’ve discovered that there is just dirt under all those leaves. No grass or other ground cover. I want to start raking near my back porch stairs to avoid wet leaves being piled up against the wood, but I can picture the bare dirt turning to mud very quickly if I do that. Is there any ground cover that will survive being smothered by leaves? I want to at least plant something around my back porch, but I’m curious if there is anything I can or should plant under the rest of the leaf pile. Thank you for your help!
- Hello! It sounds like you have a beautiful, mature Southern Magnolia (Magnolia grandiflora). Along with the beauty of these magnificent trees comes the never ending pile-up of their large leaves. Since you prefer to keep the area tidy (and to avoid potential rotting around porch posts), I would recommend routine cleanup with a leaf blower, and planting some nice, shade loving perennials. Once you have some plants in place under the tree, a leaf blower is really the most practical way to keep the area tidy (as a side note, if you happen to compost it really is best to shred the Magnolia leaves with a mulching mower first). As far as plant options under your tree, I would recommend any combination of the following: native ferns, hellebores, pachysandra, or hosta (if you have no deer problems). All of these plants tolerate shade, and should allow you to periodically use the leaf blower to keep things tidy. Magnolia trees have shallow roots, often near the ground surface, so take care when you do your planting to avoid damage to those roots. Good luck and happy gardening!
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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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Leafminers...
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Date Posted: Tue, Aug 17 - 8:46 pm
- My broccoli, cabbage and cauliflower has white vine like lines on the leaves. What are they and how do I get rid of them. My plants look like they are not thriving now.
- It sounds like you've got leafminers. They have a broad range of host plants and they seem to like your garden. The first thing to do is remove the affected leaves and dispose of them in the trash (not in compost). If you check the underside of the leaf you will most likely see small white eggs, you don't want those to hatch, so straight to the trash. There are several generations of this pest in one season so you will need to keep a close eye out for signs of their existence. You may see eggs, larvae and flys. Sometimes using sticky traps and row covers for the flies works well. If just removing the affected leaves isn't keeping the numbers down you might try using neem oil or beneficial insects such beneficial nematodes or parasitic wasps. I personally haven't had experience with beneficial insects as an intervention so I don't have any particular insight there. Start with removing the affected leaves and checking plants frequently for eggs and tunneling larvae. Good luck and good gardening!
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Lavender siting, growing
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Date Posted: Tue, Aug 17 - 8:42 pm
- I have 3 small (6 " high) lavender plants. Where is the best place to plant? Do the roots get deep/wide? How long will it take for them to get 2 feet tall? Any best practices? Thank you.
- Hello there, lavender is a lovely plant and generally not fussy if given the right conditions. It's partial to warm and dry, not so fond of humidity, but if you plant it in area with good air circulation that should help. Also, it needs well-draining soil, no compacted clay for this plant. As far as height and growth, without knowing the cultivar it's hard to say but it will probably put on a couple of inches of growth each year and most varieties are in the 2-3 foot height at maturity. Enjoy the fragrance!
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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!
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Majesty Palm dying
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Date Posted: Tue, Aug 17 - 8:40 pm
- I have a majesty palm that sits in a corner by my living room windows. It doesn't get very much light there (but I don't have anywhere else to put it) so I added a growth light. The light delivers red and blue light for 4/hrs every night and is set up about 5 feet away. I also have a terracotta automatic water in the soil, which keeps the soil most without being soggy. Nonetheless, the plant is dying. The fronds have been turning brown from the outside in and now I've had to cut away two complete fronds which and a third is on the verge of death. What am I doing wrong and is there anything I can do to still save it?
- Majesty palms are very particular about the level of light required, but it sounds like you are dealing with that effectively with the grow light. One factor you did not mention was your soil. These plants require very well aerated, loose soil which drains well. Make sure your soil is not too dense, particularly since you are irrigating with terra-cotta automatic watering. I have three majesty palms and all are sitting in north facing windows. They are getting only indirect light all day. One of them was initially in densely packed soil, and was not doing well, so I repotted in a very loose soil and the palm seems much happier. Also, these plants love to be fed. I use a miracle-gro continuous release palm plant food, so you may want to try that.
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Tomato-Blossom End Rot
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Date Posted: Tue, Aug 17 - 8:37 pm
- I'm just starting to see fruit on my tomato vines, but unfortunately they look to already be developing blossom end rot. I'm using a mixture of organic soil with fertilizer and perlite, and I'm not sure if the plant is salvageable. What can I do to help this plant? And what advice can you give for other tomato plants to prevent this blossom end rot? Is there something I can apply early on to prevent this? Thanks!
- Hello there, This is a pretty standard issue with tomatoes. Generally, the cause is inconsistent watering and/or a calcium deficiency. So the first step would be to establish a consistent level of watering for your plants. Of course, Mother Nature plays a role here as well, you can't control that. If you're sure that watering is not the problem, then you need to think about calcium. Without testing the soil you won't know the level of deficiency. But if you want to proceed, there is a short-term fix. I haven't tried this myself because the cause for me was generally a watering issue, but you can spray the plant with a calcium solution. That will buy you some time to increase the calcium content in your soil. There may be enough calcium in the soil but the ph of the soil may be preventing the plant from absorbing it. I don't understand all the chemistry of this but soil ph is the root of plant happiness. A ph of around 6.5 will do. Try adding some fast-acting lime (don't use dolomitic lime) and working that into the soil about 12 inches deep.The lime frees up the calcium from the soil. As I said previously about chemistry....This is a time-honored practice so it should work for you if, in fact, you find that watering is not the problem. If you would like to have a soil profile done, please let us know and we can send you a soil test request kit. Good luck with the tomato harvest!
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Japanese Holly Dieback
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Date Posted: Tue, Aug 17 - 8:37 pm
- There is a hedge at the front of my property. Someone years ago told me they are Japanese hollies. I found a tag on a bush in the back yard which I believe is the same plant--it's Ilex crenata 'Bennett's Compacta'. They had been very healthy and growing almost too well for nearly 12 years until this spring when one bush turned brown in a matter of days. I cut out all the brown and there is some new growth near the base, but I have 2 questions; 1. What are likely causes of the die-back? 2. What are the chances that this will affect the other bushes? Since it's the front of the property it's already unsightly--looks like a missing tooth--but I don't want to replace the one diseased bush in the row if they could all be in jeopardy. Thanks for your help. Shelley
- Hello there, Without seeing the plant and the place it's situated, my best guess about the origin of the dieback is black root rot. I am attaching a link here from Virginia Tech with an information sheet. It's a tough problem. If you believe that's why your shrub succumbed and since the hedge has served you well for 12 years, it may be time to replace it. Of course, any replacement would have to be a variety that will not be susceptible to this root rot. Let us know if you have further questions. Best of luck.