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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!

Removing Kudzu

    Date Posted: Thu, Jul 27 - 12:13 am

    Question

  • What can be used to get rid of the Kudzu that has taken over the Camellia bush?
  • Answer

  • The dreaded kudzu! For successful long-term control, the extensive root system must be destroyed. Any remaining root crowns can lead to reinfestation. Kudzu grows from seed and from root crowns. You can see these root crowns if you follow a vine to where it roots in the soil. Dig just a little around it and you will see several buds, new sprouts, or mature vines emerging from just at, or below, the soil surface. This is the root crown. To stop new kudzu vine growth, cut just below the root crown and remove it from the soil. Kudzu cannot regrow from below the root crown, and it does not sprout from any lateral roots. Sometimes vines, which can root, may be buried under a few inches of organic matter and leaf litter. This gives them the appearance of lateral roots, but they are not. Buried vines make control more difficult because they are hidden and may produce many new shoots. Use a shovel or pick axe to expose the base of the root crown. Then use a sharp hatchet, axe, or a small handsaw to cut the root below the root crown. A shovel or hoe is not adequate for the job as the roots are very fibrous or woody. Pruning shears may work for severing smaller root crowns, but will not work for large root crowns. It is also a good idea to plant native grasses in the fall after removal to control erosion and spread of kudzu and invasion of other weedy plants which may colonize the site after kudzu dies. Good luck!

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!

Building soil

    Date Posted: Sun, Feb 26 - 5:45 pm

    Question

  • We are making new raised beds for flowers and veggies. We are designing them with a wooden frame and then approaching the layers as a lasagne garden. My partner is thinking he can use only mushroom compost and cardboard to fill these beds but from what I read we need about 75% soil and 25% mushroom compost. Is this accurate for Richmond soils? Thanks for your insights on how to best lay the ground materials for thriving flower & veggie beds. Much appreciated, Jāna
  • Answer

  • Hello Jana, My go-to resource for soil building is the permaculture guide--Gaia's Garden. The recommendation for building soil through compost is to use half green matter and half brown (to attain a good ratio of nitrogen to carbon). Green matter would be leaves, grass clippings, kitchen scraps (but also manure) and the brown would be dried leaves, hay (includes weeds), straw, pruning trimmings, and wood shavings or similar. The book discusses all issues such temperature of pile, size, turning, etc. The mushroom compost is great but I think the combination of materials will lead to a longer stretch of fertility in the beds. With different materials leaching their nutrients at different times. The beds will consume a lot of mulching material. One way to deal with this is to use any brush you may have collected and build hugelkultur beds. They are basically a mound of brush (tamped down), well watered and covered with organic materials, compost and soil. So you may want to use a combination of hugelkultur and organic matter with a good topping of mushroom compost. I recommend reading Gaia's Garden's chapter 4-Bringing the Soil to Life. The author's favorite method for doing so is sheet mulching (lasange gardening). Happy gardening!

Pruning Hydrangea

    Date Posted: Fri, Feb 18 - 12:22 am

    Question

  • how far back can i cut my hydraingia
  • Answer

  • 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!

Trellising Blackberries

    Date Posted: Wed, Aug 18 - 1:44 pm

    Question

  • 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
  • Answer

  • 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!

Mulberry debris

    Date Posted: Tue, Jun 22 - 4:11 pm

    Question

  • A neighboring mulberry tree drops berries into my small patio/mulch bordered backyard. We sweep the berries off of the patio daily but are not able to effectively clean the mulch area where the berries fall. I've noticed an uptick in bugs, birds, weeds/growth/sprouts, etc. in the mulch. 1) Should I work harder to clear the mulch area of these berries or is it okay to let them fall and naturally "decay" in the mulch? 2) What would be the best groundcover (mulch, dirt, stones, etc.) to be under a mulberry tree constantly dropping berries?
  • Answer

  • Hello there, As you know mulberry trees are prolific berry producers. I don't see any reason not to let the berries compost into your mulch. However, it would be a good practice to hoe the mulch every now and then to prevent the berries from growing into trees. Also, they will still attract the birds and bugs that you've mentioned so that may not be a satisfying practice for you. One option would be to change the mulched area to tightly laid pavers. Then you could sweep that at the same time you sweep your patio. I suggest tightly laid because any open ground will provide a hospitable place for the mulberries to sprout. They are determined plants. Another option would be to have a polite conversation with the owner of the tree requesting that the overhanging limbs on your property be trimmed. If the tree is properly pruned, the offending branches on your property would be removed and the rest of the tree should be pruned for balance. You may want to bring this to the owner's attention to ensure a correct pruning job and to make sure all parties are happy with the results and the tree is properly preserved. Hope the helps!! Let us know if you have further questions.