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Creeping phlox

    Date Posted: Tue, Jun 21 - 9:58 pm

    Question

  • My creeping phlox was planted about a month ago. When I bought it it had some dried out looking leaves. Now it is looking more dried out at the base and many leave are turning yellow. I am wondering if there is a way to save them?
  • Answer

  • Hello there, There are a couple of phloxes that could be described as creeping. There's moss phlox (phlox subulata), which is very short and creeps, there's creeping phlox (phlox stolonifera) which is taller and creeps, and there phlox divaricata also taller and creeps. However, I think they all suffer from similar problems so it may not really matter which one is in question. The plant could be suffering from some fungal disease or it could be a virus. A fungal issue could possibly be resolved. A viral problem cannot. It's impossible to know which issue you have without a diagnosis but you could try using a fungal spray (there are some less toxic sprays on the market that can be used safely if you avoid spraying when insects are busy) and if the plant rebounds you know that was the problem. If it doesn't rebound, it's viral and you should pull it up and dispose of it in the trash rather than compost. Sometimes compost won't kill the pathogen, so to be on the safe side I'd use the trash bin. Good luck! Let us know if you have further questions.

English Ivy

    Date Posted: Sun, Jun 05 - 1:10 am

    Question

  • Hi, I have a question about some plants in my backyard. I think I have some kind of ground ivy, and it has something wrong with it. I'm not sure if it's fungus or insect activity. The leaves have small “bubbles" where the leaves material has ballooned in places. Each bubble is the size of a pea. On the underside of the leaves, inside the bubbles, there are clusters of little white specks. I have pictures, but I'm unable to post them here. What is causing this? Do I need to do anything about it? Will it spread to other plants? Thanks!
  • Answer

  • Hello there, I am making an assumption that you are referring to English ivy. I haven't seen the problem you're describing myself but I found some information on the Virginia Tech website. Again, I based my search for information on the subject being English ivy. If you think it's something else you can try searching for it on this website. There are photos you can refer to when you get the search results. Here is the website address--https://apps.cals.vt.edu/ppig/ --Select Woody Ornamentals for Plant Type and English ivy for Plant Common Name. It should return 2 entries. One will be for Bacterial Leaf Spot and the other will be Anthracnose-a fungus. I hope this helps! Let us know if you have further questions.

Pests and diseases

    Date Posted: Mon, Apr 11 - 6:11 pm

    Question

  • Hi there, We just moved into our home last fall and I’m just getting into gardening. I have a few issues I’d love some help with, namely, treating leaf diseases on a young azalea with freeze damaged buds, a large overgrown camellia with what I think is tea scale and flower blight, and leaf spots on mophead hydrangeas. There’s so much information out there but would love help identifying these issues correctly and providing timely care while we’re still in early Spring. Thank you! Emily
  • Answer

  • Hello Emily, Good to hear you've inherited a nice garden. There is always a learning curve with a new garden. I think the best way to answer your questions is by using the Plant Disease Clinic. The Richmond VCE office is closed until a new agent is in place. In the meantime, the Chesterfield office is generously offering this service. The clinic does charge a fee of $35 for samples. I'm including a link to their office so you contact them directly for instructions on the process-- vce@chesterfield.gov Best of luck and happy gardening!

Pests & Disease -- Rosemary

    Date Posted: Mon, Feb 21 - 7:57 pm

    Question

  • I seem to have little brown nodules all over my Rosemary and it seems to be reducing its vigor and making the leaves look like they have aphids one them [the green is draining out of them]. Do you know what causes this? does it make the rosemary not good for eating? If I treat it, what would I use and how would it effect eating it? I coudl send a photo if that would help. Thank you. Lynn
  • Answer

  • Hello there, Based on your description I think the problem is bacterial leaf spot. I can't say for certain though. I've attached a link from the Missouri Botanical Garden about bacterial leaf spots and blights. If you open the link and scroll down, you'll find 2 photos of rosemary side by side. The one on the right may depict the problem you are encountering. Be sure to read all 8 items about prevention and control. You'll read that there is not much to be done if the plant is too far gone. You can try cutting the stems that are affected but be certain to clean your tools as directed in the article. Depending on the severity it may be wise to properly dispose of the plant and replace it with a healthy new one while adhering to all the points made about prevention. I hope this helps solve your problem. Sometimes replacement is the best choice https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/bacterial-spots.aspx

Black-eyed Susan

    Date Posted: Sat, Oct 02 - 4:51 pm

    Question

  • 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?
  • Answer

  • 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!

Sckip Laurel wilting and drooping

    Date Posted: Tue, Sep 07 - 4:11 pm

    Question

  • 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.
  • Answer

  • 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.

Boxwood with patches of brown leaves

    Date Posted: Tue, Aug 17 - 8:35 pm

    Question

  • 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?
  • Answer

  • 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.