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Pruning Hydrangea
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Date Posted: Fri, Feb 18 - 12:22 am
- how far back can i cut my hydraingia
- Hello there, The first question I have is: why do you want to prune your hydrangea? The main reasons for pruning are that the plant is either too large or there is dead or possibly diseased wood that needs to be removed. The other question I have is what type of hydrangea are you thinking of pruning? There are numerous types and various species. I am going to assume that the plant in question is what is commonly known as a bigleaf hydrangea (because those seem to be the most prevalent variety). These typically have the mop-headed type of bloom or a lacecap bloom. Older varieties of these will only bloom on old wood but many of the newer varieties bloom on both old and new wood. The reason this distinction is important is that if you have a plant that blooms on old wood and you prune those stems you will be robbed of blooms come summer (you will have cut them off). That would be a shame. If you're not sure if you have a new or old variety, it is best to approach pruning very carefully. Attached is a link from a VA Tech publication with photos of both old and new stems so you can see the difference. Look for the heading in the publication that says Bigleaf Hydrangea and then scroll to the photo of the plant in winter to see which stems should be cut. While you are looking at the publication, review the other types of hydrangeas listed to be certain about the type you have. https://chesapeake.ext.vt.edu/content/dam/chesapeake_ext_vt_edu/files/pruning-hydrangeas.pdf. While you are pruning stems be sure to cut any that look dead or diseased. Clean your pruners after cutting diseased stems. Please keep in mind that you may not need to prune your hydrangea. If you enjoy the size it currently is and it doesn't seem to have any dead wood, you've saved yourself a gardening chore. Happy gardening!
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Strawberries Varieties for Richmond
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Date Posted: Sun, Feb 13 - 9:09 pm
- What are the best varietals of strawberries to grow in RVA?
- Hello there, Glad to see that you are thinking Spring! You have a number of choices for this area. There are several types of strawberries: June-bearing, day neutral and ever-bearing. I believe you'll be most successful planting the June-bearing varieties here. The other two options are more suitable for cooler climates. Some basic requirements for fruiting are to make sure you're planting an area that gets full sun (usually 6-8 hours a day), most likely near to your vegetable garden. However, do not plant in sites where tomato, potato or eggplant were previously planted to keep down disease (verticillium wilt and some others). Be aware that strawberries will reproduce quickly, this can be both a pro and con depending on how much space you have. Clip the runners if you are most interested in having larger berries on the mother plant. It's often suggested that strawberries can be integrated into an ornamental garden but I've never had very good luck with that approach but feel free to experiment. They could make a nice ground cover in the right setting. Some recommended varieties from VA Tech are: June Bearing--Sweet Charlie, Camino Real, FlavorFest. Of course there is always our native strawberry from which many cultivars are produced--fragraria virginiana. If you would like more information on this subject, I've attached a link. https://ext.vt.edu/content/dam/ext_vt_edu/topics/agriculture/commercial-horticulture/small-fruit/fruits-in-the-home-garden.pdf. Best of luck with the berries!
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Ambrosia beetles-Dogwoods
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Date Posted: Tue, Oct 05 - 4:24 pm
- Ambrosia beetles-dogwoods
- Hello again, I have a few questions about your trees. I'm wondering how they were diagnosed. Did you see the frass tubes (kind of looks like tooth picks) on the trunk? Was there blue staining in the sapwood when they were removed? You may also have seen 'sawdust' at the base from the process of tunneling in the entry holes. Those would be definite indicators of the beetle. Generally, they attack trees under stress, such as drought or lack of appropriate amounts of scheduled watering. The pests may have been in the trees when you purchased them from the nursery. If so, the guarantee from the nursery may cover your loss. Assuming the reason your trees failed was due to ambrosia beetle and not another pest or disease, the arborist I consulted said that planting in the same location would be fine. I don't believe they have created any trees to be resistant to the ambrosia beetle. That being said, I think the chief thing is to provide the best cultural environment for the trees to survive. Well-draining soil is key along with proper placement and watering until the trees are established. Without knowing the exact environment you are planting in it would be difficult to recommend a particular tree. Look online for a list of native trees for this area and then consider the location you have and whether or not that tree would be a good fit. Consider the amount of light, moisture, available space for mature height, etc. Sorry those dogwoods didn't make it. Best of luck with your next choice.
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Black-eyed Susan
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Date Posted: Sat, Oct 02 - 4:51 pm
- Some of the leaves on my Black Eyed Susans have turned brown. Could this be a fungal infection? And if so, how can I treat it? Also, could you recommend a Black Eyed Susan that is disease resistant?
- Hello there, Without knowing the variety, I'm going to guess that it's Goldsturm, (it may not be but that is the most popular variety). These plants can succumb to fungal and bacterial issues. I can't specifically say what is ailing your plant but you can implement a few cultural changes to see if that helps. Your plants should have good drainage AND good air circulation. Soil and air would be the first factors to check. If you think you have that covered and the plant is not recovering it would be wise to remove the plant and discard it in the trash. If you have other plants that are in good health still you may want to treat them preemptively with a baking soda or neem spray. Additionally, if you want to plant again in that same spot where the ailing plant was you will need to use fresh soil in order to avoid a repeat of the situation. I came across a helpful list of species and cultivars of rudbeckia on a website of an organization based in Baltimore called Blue Water Baltimore. There are many other rudbeckias that may be more suitable for your particular situation. Here is the link--https://bluewaterbaltimore.org/blog/how-to-choose-a-black-eyed-susan/ There are many lovely varieties to choose from and those that can handle humidity would probably be a great choice. Good luck!
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Sckip Laurel wilting and drooping
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Date Posted: Tue, Sep 07 - 4:11 pm
- I have some skip laurels that are wilting and drooping. There are two large shrubs in the midst of 30 total. One that is really bad is between two that are perfectly healthy. These were planted about 13 years ago. I lost one last year. That was a new plantings. This one is old and the surrounding shrubs are fine. I’d like to get a sample sent to a lab to test for a bacterial or fungal infection and or have someone come out to take a look I’m happy to take pictures and send it please let me know you can call me at 415-417-9997 that is my cell phone or email is fine too thanks look forward to your response.
- Hello there, Sorry to hear this. This plant is generally without problems as you know. I've reached out to an extension agent to get the process of getting your sample to the clinic in the works. It may take a little longer than usual since Richmond is without an agent at the moment. I've reached out to Henrico. If you don't see a posting here with that information in several days, please send me another email as a check in. Thanks for your patience. I hope we can get you the answer you need.
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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, it’s 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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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. I’m 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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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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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.
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Boxwood with patches of brown leaves
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Date Posted: Tue, Aug 17 - 8:35 pm
- I just bought a house and I have a boxwood bush in the front that has patches of brown leaves. Is this that blight that I've heard people talking about? would it be a good idea to remove the bush or is there something I can do?
- Thanks for your question. This does sound like it could potentially be boxwood blight which is a fungal disease, and for which there is no cure. This disease first appears as lesions with dark brown edges on the leaves and black streaking on the stems. The foliage then turns brown and falls off. Observe the leaves and stems on your boxwood for these signs. If your plant is minimally affected, you can cut off affected branches, clean up debris from the ground, bag the trimmings, and put in the trash (do not compost). You may then be able to keep the disease at bay by spraying a chlorothalonil-containing fungicide every 7-14 days. Be sure and sanitize your garden tools with a 1:9 bleach to water solution to avoid spreading the disease. If your boxwood is heavily infected and unsightly, it may be easiest and safest in the long run to remove the whole plant. It’s also important to know that the spores from the infected plant can remain in the soil for 5-6 years, so if you want a replacement plant be sure and select a boxwood cultivar with a high level of resistance which will not require a fungicide treatment.