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Yellow Spots on Rhododendron Leaves
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Date Posted: Wed, Aug 18 - 2:01 pm
- My large rhododendrons have some yellow specked leaves. Been watering every other day. What are you suggestions
- Hello! Thanks for your question. Given our recent warm and humid weather conditions, the problem you are having with your rhododendron is certainly not uncommon. I suspect your plant has a fungal condition called leaf septoria (yellow leaf spot). It sounds as though the condition on your plants is not widespread at this point and there are a few steps you should take to rid your plants of this fungus. First, remove the affected leaves to get rid of as many fungal spores as possible. Secondly, take away any fallen leaves from under the plant and keep the area clean. Discard all removed leaves in the trash (not compost). Mulch the area under your rhododendrons; this helps prevent spores from spreading. It will also help retain/absorb the water when you are watering the plants, and reduce splash upwards. And when you water, itâs best to use a soaker hose at the base of your plants, versus overhead watering. Watering overhead and watering in the evening can increase fungal disease development on these plants. You can also apply a simple, all natural spray solution consisting of the following: one quart of water in spray bottle with 1 teaspoon of baking soda; add 1/2 teaspoon of canola oil and a few drops of dish soap; shake the solution well and spray on the plants. Good luck with this - improved weather conditions in the coming weeks hopefully will help as well! Let us know if you have further questions. Thanks! And of course keep a close eye on your other grow bags with your other vegetables for any similar signs. Good luck with your garden, and wishing you a strong yield!
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Worms/Caterpillars in Grow Bags w/Vegetable Plants
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Date Posted: Wed, Aug 18 - 2:00 pm
- Like many in the midwest, I have started a victory garden of sorts over the past few months, mostly in large grow bags on a pallet on my deck. This morning I noticed that the grow bag containing my romaine lettuce was full of either some very freaky worms or caterpillars, and while the worms seemed to be contained to the romaine bag, I worry for my adjacent chard, collard greens, and tomato bags. After a quick google search, I discovered two options that I was interested in: bacillus thuringiensis or diatomaceous earth, but I would like to know what option would be the most efficient in terms of use of product and frequency of applications and also the most environmentally friendly. If there is a better option than those two, I would be happy to learn also. Thank you!
- Good afternoon! Thank you for your question. My first thought when I read your question is that the solution certainly depends on the type of worm or caterpillar-like creature in your grow bag. If you have common earthworms or red wigglers, Iâd say leave them alone as they are beneficial to the quality of the soil and will benefit the overall health of your plants. But it sounds like you may have something different which could ultimately harm your plant. If, for example, you have cutworms (which resemble caterpillar) and/or leaf miner larvae in your soil, you want to remove these. First, I would separate the infested grow bag from your other grow bags which contain your other vegetables. I would then pick off the visible worms/caterpillars with your fingers and submerge them in a container of warm soapy water. Although the products you mention may be effective at killing the catepillar-like creature you have, they do have harmful attributes. They may be considered organic but they still have low levels of toxic ingredients to bees. I would use an insecticidal soap solution such as neem oil or simply mix 3 tablespoons of dish soap to 1 gallon of water and pour into your infected soil. Apply this process weekly. And if you see any of these caterpillars on the plant leaves, pick them off and spray the neem oil/soap solution directly onto the plant - repeat the process weekly. And of course keep a close eye on your other grow bags with your other vegetables for any similar signs. Good luck with your garden, and wishing you a strong yield!
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Lawn options-seed or sod
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Date Posted: Wed, Aug 18 - 2:00 pm
- Iâm trying to decide what to do about my front lawn. Itâs a little under 60 square yards. Everything is killed off and tarps are covering the ground now to keep weeds from growing. There is no shade, all day sun. I would like to know if Tall Fescue is the best choice and also should I seed or sod. Cost is not the issue since itâs a small area. I hope you can give me some advice.
- Well, I know you didnât ask this but what about foregoing a lawn and planting a dooryard garden instead?. Iâm not much of a grass person. A patch of clover is more to my liking, at least it gives the honey bees a place to land, adds some nitrogen to the soil. Maybe a combination of a lovely shrub border, a small tree, a mix of tall and low-growing perennials, groundcovers? Since it's a small area the expense wouldnât be staggering and you can always phase in the plantings. Something to consider.... That being said, I think youâre doing a good job of preparing for a fall planting by covering the space and killing off the weeds. If I haven't persuaded you to take a different approach, Iâll try to answer your question about seed or sod. You didn't mention why your lawn was "killed off". Is there an issue with the soil? If so, you should request a soil test kit from the Richmond VA Cooperative Extension Main Office: (804) 786-4150. The results will let you know what, if any, amendments you'll need to add. I think the choice of a tall fescue is fine and fall is a good time to start a cool-season grass. When purchasing seed, check the bag to make sure you are buying all seed and no filler. Look for the two Virginia-Maryland labels affixed to the package so you know you are buying seed mixtures or blends which comply with the quality standards of the Extension Divisions of Virginia Tech and U of MD. First, you'll need to prep the soil. Remove all the dead weeds you've killed by covering and make sure there are no roots left in the ground. This can be tedious but it will pay off in the long run. Work in any amendments your soil test dictates. Add a layer of compost, you can till it in, or if your soil isn't compacted, adding 1-2 inches to the surface should suffice. Grade the soil with a rake so the surface is smooth and uniform. At this point you can seed. Disburse the seed with a spreader and go back and forth across the lawn, then in a perpendicular direction, attempting to get an even amount of seed across the surface of the lawn. You can add another fine layer of compost so that there is good contact between the seed and soil. (For a larger lawn you would roll the seed at this point.) Then you'll need to water immediately thereafter and continue to water until the seed germinates. (Be careful when watering, keep the soil moist, don't wash the seed away.) After that a total of 1-2 inches of water a week should keep the grass in good spirits. Hand pull weeds. An established lawn could take up to 2 years with seed. If this doesn't sound like fun, you can clean up the soil as above, amend as needed, grade it with a rake, and lay sod. Do not let the sod dry out. You'll need to water the sod daily for a couple of weeks (of course, less if there's rain). During this period the sod will be putting down shallow roots into your soil bed. Avoid walking on the sod during this period. After about a month the sod will have established a better root system. Around this time it will need to be mowed. Set the mower to 3 inches. The sod will provide a quicker route to a nice green lawn if the expense is acceptable. I hope I've covered all your options. Good luck with the project!
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August Beauty Gardenia
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Date Posted: Wed, Aug 18 - 1:59 pm
- I have purchased an August Beauty Gardenia shrub and would like to give it the best chance to thrive in my yard. Would it be better to plant it in a spot with the most sun (also near the house), yet fairly exposed as no other plantings near, or in a bed which gets a good amount of sun and has established hedge (hollies) which may offer protection from the elements? Thank you in advance for your help.
- What a beautiful plant selection! Youâll enjoy the long blooming season of this plant, and of course their wonderful fragrance. In terms of best location, you should keep two things in mind. First, to ensure a prolific bloom all summer, you want to maximize early day sun exposure. If one of your described locations is on the east side of your yard and gets several hours of early day sun, that would be ideal, especially near a walkway or porch where you would enjoy the fragrance. I would try to avoid a location that is fully exposed to our late afternoon hot sun during July/August. Secondly, consider your soil and drainage in selecting your location. Gardenias like evenly moist acidic soil which provides good drainage. You want to avoid planting your gardenia where its roots would compete for moisture with nearby trees. The bed with hedge hollies would be fine if you have several hours of early day sun there. If you are planting your new gardenia this time of year, be sure and add plenty of organic matter to your soil, mulch around your plant, and provide plenty of water during this last phase of summer. Enjoy your beautiful plant, and let us know if further questions!
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Watering roses
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Date Posted: Wed, Aug 18 - 1:48 pm
- Hi i have a row of drift roses on the front on my yard, they are in full sun. I had been watering them every other day with the lawn but noticed that a few bushes had yellowing leaves which then turned brown and crispy. I am assuming that is a sign of being overwatered? Any suggestions on how to make the flowers last so they donât turn brown so quickly in the heat? Thanks!
- Hello there, My first instinct is that you are, in fact, over watering your roses. How long have the roses been planted? If it's been a few years then watering once or twice a week should be sufficient. Is the soil well draining? Roses don't want to sit in consistently wet soil. Are you able to gauge how much water, in inches, your roses are receiving. one to 2 inches of water (rain+water combined) should keep them healthy. I believe that's about 4-5 gallons of water a week. Also, I don't think the heat is causing the roses to brown but the effects of over watering are. Back off on the watering a bit. Try to avoid the foliage and water the soil around the plants and see that they get soaked rather than sprinkled. I suspect that less water weekly (avoiding the foliage whenever possible) and a couple of good soaks a week will make you and your roses happier. Good luck!
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Yellowing Aster
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Date Posted: Wed, Aug 18 - 1:46 pm
- Hi we have a row of fall aster and notice that this year and last as the rest of the plant grows large and bushy the base starts to get yellow and then dries. the plant seems to be getting enough water. Is this normal?
- Good morning, and thank you for your question! My first thought is that you may have a watering issue. Iâm assuming your aster plants otherwise have normal growth, are not stunted, and bloom well. Asters do prefer well-draining soil and like to keep well watered. However, they do not like overhead watering or sprinkling. Doing so can result in development of a fungal disease. Watering should be done at the base of the plant where fungus would first develop. It also helps to use a good organic mulch around your aster plants to help retain moisture and prevent splash to the lower leaves which can cause the yellowing. As a side note, be on the lookout for leafhoppers on your aster. They can spread bacterial disease (phytoplasma), which is a more serious problem to deal with, but with this you would likely notice other symptoms such as stunted growth and deformed flowers as well. If those symptoms develop, the plants would need to be removed as there is no cure. It does not sound like you are experiencing these specific problems with your aster, and proper watering and mulching would be the best first steps to implement. Good luck with this, and let us know if further symptoms develop.
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Cilantro regeneration
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Date Posted: Wed, Aug 18 - 1:45 pm
- I had to go out of town and my cilantro got neglected. What can/should I do now? It has gone to seed and there are no more leaves. I cant figure out how to insert a photo or I would.
- Hello there, This is always an issue with plants and time away....But since cilantro is so versatile, I don't think you have a problem. First, you can actually use the seeds for seasoning. But, if you don't like that idea, simply plant the seeds you now have and soon enough you'll have a new crop of cilantro. It's a plant that doesn't especially like hot weather (because it 'bolts' or sets seeds) so you can't have the same plant for a long season but if you just keep planting the new seeds that set you'll have a continuous crop. It's a pretty quick turnaround for harvesting the leaves, 3-4 weeks. If you sow new seed every couple of weeks you can keep that herb going through fall!!Good luck with the project!
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Trellising Blackberries
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Date Posted: Wed, Aug 18 - 1:44 pm
- I am wanting to grow blackberries in containers. I have a full sun spot behind my house. Do you think galvanized feeder troughs would be a good thing in which to plant them? And was planning/thought I could trellis them on my fence - do you think that would work? Thank you
- Hello there, that sounds like a great scheme. The troughs should be fine. Galvanized containers are only a problem when they start to corrode so starting with new ones will be fine and serve you for many years. You didn't mention the type of blackberry or the height of your fence. Assuming you are using erect blackberries they will probably top out at 4-5 ft. tall. So factor that in with the height of your planters. If your trough is a foot high add in the mature height of the bushes at 5 feet. Assuming your fence is 6 feet high your good to go. Even if the fence is a bit shorter it will still work. Blackberries can get pretty tangled so you're smart to want to control them a bit with a support. Generally, you will cut down the cane after it has fruited and you've harvested. However, the pruning can vary depending on whether the plant fruits in summer or fall so just be sure to get all that information when you select a variety. It would be good to have some air circulation behind and around the plants so hopefully your fence isn't solid boards. You might wind up with some space in the front of the berries which could be a nice spot for growing herbs. Good luck with the project!
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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 youâve taken this approach twice and theyâve 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 youâve 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 1â 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 weâll 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! "