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Browning Dwarf Arborvitae

    Date Posted: Wed, Oct 11 - 12:47 am

    Question

  • Dwarf Arborvitae has brown sections, on am effort to cut them out, it appears black underneath. What is happening? Thank you.
  • Answer

  • 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!!

Japanese Spirea

    Date Posted: Tue, Oct 10 - 5:24 pm

    Question

  • My japanese spirea has large dead sections that I just trimmed back. I don't see any bigs. Any ideas? And should this be cut way back in fall?
  • Answer

  • Maintenance pruning for spirea can be done anytime of year and damaged or dead branches should be removed as you see them. When removing these branches, be sure to prune back to a point where the branch is still healthy, or back to the ground if the damage occurs throughout the length of the branch. An overall pruning can be done in late winter, just before new leaves begin to appear. Dwarf varieties (which typically grow 1-3ft tall) can be cut back to 4-6" above the ground. Taller growing varieties can be cut back to 10-12" above the ground. Without more information, it is difficult to say what might be causing the dead sections on your plants. These plants do not require a lot of water, and typically do well on rain water alone unless there is an extreme period of drought. You could monitor your soil to be sure it is draining well and not staying too soggy and moist which could lead to disease issues. One thing to keep in mind about Japanese spirea is that it is a non-native invasive plant. It has small seeds that can last for years in the soil making it very difficult to control. Once Japanese spirea is established outside of its intended areas, it can quickly crowd out native species. Unfortunately, the best control method is to remove existing plants. There is a native spirea that could be considered as a replacement: white meadowsweet (Spiraea alba). I hope this information helps you! Happy gardening!

Maples for Urban Landscaping?

    Date Posted: Thu, Sep 28 - 12:43 pm

    Question

  • I need to replace a diseased Dogwood. I was thinking of a Maple tree but I am concerned of the root system. There are so many varieties of Maple, I don’t know where to start. The new tree would be giving shade to a front porch and two Hydrangeas. Can you give some guidance?
  • Answer

  • This is a great question. Generally, maples are known to have shallower root systems, but it can depend a lot on the soil conditions. A few things to think about when you are selecting a tree for this space are if the tree is being planted near sidewalks or a driveway, what your soil conditions are like, the amount of sun or shade it will get, and also to look up for power lines. Red maples are generally faster growers and are also native to our area, but they may have shallower root systems. Japanese maples tend to be slower growing but are not native. Sugar maples are also an option but you would want to be sure to select heat tolerant varieties for the Richmond area. Another alternative is Yellowwood. They have nice big leaves, beautiful form and flowers, tolerate the heat and don't get too big. The University of Illinois Extension has a great tree selector tool that you may also find useful: https://web.extension.illinois.edu/treeselector/search.cfm Good luck!

Stunted vegetable garden

    Date Posted: Sat, Aug 12 - 6:55 pm

    Question

  • My vegetable garden has been stunted in its growth this summer and I’ve been trying to figure out what I can do differently. I think we may have some Red Thread in the yard.
  • Answer

  • I think many local vegetable gardens have experienced some stunting this year. The prolonged cooler weather we had at the beginning of the summer seemed to have a big impact on plants that were put in the ground in late April and May. In addition, we have had several periods with very little rain to help keep gardens watered which has also been having an impact. Before planting next year, its a good idea to do a soil test to see where your soil could use some support. Soil tests are available through the master gardeners at your local library. You can use these results to ensure you are planting in a robust healthy soil that is ready to provide a good home to your plants. Also, if you aren't already doing this, I would suggest fertilizing your garden with an organic fertilizer. Organic fertilizers slowly release nutrients giving a steady supply of food to your plants without disrupting the work of earthworms and other beneficial organisms. Follow the recommendations on the label for frequency of fertilizing. I'm not aware of nor have I been able to find any literature on red thread having an impact on anything other than turf grass. I'm not sure if you mentioned that in correlation with your concerns about your vegetable garden or as a separate concern. However, if you were looking for recommendations to deal with the red thread as well, fungicides are not usually advised for red thread control on residential turf for various reasons. The disease is largely cosmetic. Unless environmental conditions that promote disease development persist for extended periods, the turf will recover — usually with no lasting effects of infection. Good luck and happy gardening!

Ilex glabra-Inkberry

    Date Posted: Thu, Apr 20 - 8:37 pm

    Question

  • We planted 5 ilex glabra bushes in October. One of them suddenly (within less than 12 hours) had it's leaves turn brown/black and fall off. The stalks and stems all seem fine, and it still has some leaves on one side. The other ones all seem fine, although they haven't grown much and have a few yellow/brown leaves. Do you know what happened and what we can do to protect the plants? Thank you!
  • Answer

  • Hello there, Sorry to hear of your situation. Unfortunately, it's difficult to diagnosis from this distance. It could be soil, possibly chlorosis, maybe spider mites. First, I would contact the garden center where you purchased your plants. Often, plants are guaranteed for a year. So if you have proof of purchase I would definitely tell them about the condition of your shrubs, what they advise and what they can do for you. You could also check in with one of the Master Gardeners that man the help desks at the library branches. Check out your local library and find out what days and times the help desk is manned. It may still be difficult to diagnose without seeing the actual planting. Bring pictures and as much information about where the shrubs are situated. You can also get a kit for a soil test from the Master Gardeners, which may be helpful to ensure the future health of the 10 plants. There is also a plant clinic but again, I would start with the garden center where you made your purchase. And, of course, check in with a Master Gardener. They are a wonderful resource.

Camellia Pruning

    Date Posted: Thu, Mar 02 - 4:57 pm

    Question

  • We have a camelia bush in our front yard that is as old as our house. It’s probably 25 ft wide at its widest. It’s in desperate need of a trim, but I have no idea how to do that! I don’t want To harm the bush at all, but I know it needs to be trimmed. I can provide pictures if helpful!
  • Answer

  • Hello there, so you have a very happy camellia on your hands. I'm going to guess it's a japanese camellia, flowering from mid-winter to early spring. The other popular variety is camellia sasanqua, which flowers in late summer, fall or early winter (depending on selection) and is generally smaller and looser than the japanese varieties. Either way you want to wait until after the plant blooms to prune (otherwise you'll miss the bloom period). Of course, if that isn't you uppermost concern and you just want to get it under control, then anytime can work. I'm attaching an article from Southern Living magazine that describes a pruning method I think will work for you. The method basically treats the shrub as a tree which would decrease your time and effort of trying to prune such a large plant back to shrub proportions. Here is the article. The last paragraph is the key. https://www.southernliving.com/garden/shrubs/when-to-prune-camellias As always use sharp clean pruners and pruning saws so disease isn't transferred to the new cuts you'll be making. Good luck and happy gardening!

Peonies

    Date Posted: Mon, Dec 05 - 4:49 pm

    Question

  • I planted two peony bushes late spring and they looked good until now. They appear to be sickly. What should I do? Are they blighted and must be destroyed? Thx
  • Answer

  • Hello there, What you are seeing is perfectly natural. Peonies are herbaceous perennials, meaning they die back every year in fall, re-grow in spring and produce those gorgeous blooms. So simply cut the stems back and rake up any debris around the plants and they will bloom for you once again in spring. They are one of the longest lasting perennials you can plant and pretty much carefree once their soil preference is met (fertile. humusy soil). Please do not destroy them. They will reward you with blooms for years to come. Enjoy!

Powdery mildew?

    Date Posted: Fri, Oct 07 - 7:05 pm

    Question

  • Hi. We have a white film on the leaves of two poppy plants we transplanted over a year ago. Cosmetically, it's not pretty. But don't know if it's harmful. It is only in the last 6 months that the film has appeared. They're under a dogwood tree, didn't know if that affected them. Can you tell me if this is harmful, and if it will impact the blooms? I don't see any buds so I fear this is a problem for the plants.
  • Answer

  • Hello there, It sounds to me that you are dealing with powdery mildew. It's a very common fungal problem, heat and humidity aid its progress. It generally doesn't kill the plant, the plant just doesn't look it's best. I don't know which type of poppy you have but I'm guessing it's one of the oriental poppies (papaver orientale), that bloom in spring? You may want to consider transplanting the poppies to a spot in full sun with good air circulation. Cut back the foliage at the end of the season and dispose of it in the trash (not the compost pile). You don't want to be harboring the spores over winter. With some more sun and air, I think you will enjoy those poppies more. Good luck!

Pests

    Date Posted: Sat, Jul 23 - 4:51 pm

    Question

  • What's wrong with my tomatoes? I've been gardening for years, but have never seen this issue with tomatoes before. This is my first time gardening in Hanover, VA. I believe the space has been used for gardening before. I didn't do a soil test. The only soil amendment has been bloodmeal. All of my tomatoes, regardless of size, look fine while green, but as they ripen, they appear to have white spots underneath the skin. When I cut them open, they all have a sort of white pithiness throughout the outer flesh just under the skin. The flavor is okay but the skins are tough and crunchy, and it's consistent throughout the 6 varieties I've planted. I haven't seen any issues with the foliage. I'm really stumped on this one but I am wondering if this is a new-to-me disease or an outcome of inconsistent watering (due to some unforeseen circumstances, they're largely surviving on what falls from the sky plus one weekly watering). I saw a few earlier in the season that have blossom end rot, but these ones don't have decay at the blossom end. Any thoughts? Thanks for your insights!
  • Answer

  • Hello there, this does sound discouraging!! I have to admit that I have never had this issue but I did a little research and found some resources that may help you. The first website is from Texas A&M. It's useful because it shows pictures of ripe fruit in trouble and identifies the problem. I'm making a guess that Cloudy Spot might be your issue. Of course, I must emphasize that this is a guess, having never seen the problem you describe firsthand. Cloudy Spot indicates stink bug infestation--https://aggie-horticulture.tamu.edu/vegetable/problem-solvers/tomato-problem-solver/ripe-fruit/. If that's right, the VA Tech website has a video on how to trap the culprit--https://vtx.vt.edu/articles/2019/10/Stink_bug_Media_Advisory2019.html, I like this solution because there is no chemical insecticide involved. The trap in the video was created to trap the bugs in homes but can easily be used in the garden as well. If my guess is wrong, you have another option. VA Tech has a plant disease clinic where samples can be tested and identified. Because Richmond City does not currently have an extension agent due to a staffing vacancy, you can contact the Chesterfield office and get the details on submitting samples. There is a $35 fee as well as paperwork that must be submitted with the sample(s). You can contact them at this email address-- Chesterfield MG Help Desk: vce@chesterfield.gov. Best of luck sorting this out!!

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.