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Planting plans for dwarf trees/shrubs
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Date Posted: Mon, Sep 14 - 12:51 am
- Hello, I hope your day is going well. I have a question pertaining to placing a dwarf tree/shrub close to the house. For the two dwarf trees/shrubs, listed below, how far from the house foundation should I place them? I am looking to place a Dwarf Globe Blue Spruce (Picea pungens 'Globosa') or a dwarf false cypress (Chamaecyparis obtusa 'Night Light' or 'Nana Lutea') in a bed that is against my house. These are both dwarf trees but also called shrubs/bushes based on their heights. I was reading about placing a tree the distance away from the house as it is tall. The mature height of these two dwarf tree/shrub is around 4-6ft after 10 years but if left unpruned for longer can be a few feet taller potentially, but I couldn't find a reliable source to back this claim. If I place them away from the house at the mature height after 10 years but do not account for however it may get after decades, would it mess up my house's foundation or do I need to not worry about it? Thank you so much for your time and help. Have a great day
- Thank you so much for reaching out to the Richmond Master Gardeners. This is a great question, and its very smart of you to be considering planting shrubs based on their mature size and not based on the size they are in the pot, as many people do. As with all things gardening, there are different perspectives that people have when considering this question, and some things will depend on your personal preference. Generally, we'd recommend shrubs to be planted at least 1/2 the diameter of the mature width away from the house plus 1 - 3 feet. So if a shrub has a mature 6' width, they should be planted at least 4' away from the house if not 5' or 6' away. The additional space leaves for a gap between the plant and house to allow airflow against the house and reduces the need for pruning. If you don't mind pruning, the shrubs can be planted closer to the house. If you would rather not prune that much, plant them farther away. It seems like you are already aware that "dwarf" varieties will happily grow beyond what their label lists as their maximum size, particularly after decades, as you mentioned. Because of this, you could also ere on planting a little farther from the house as opposed to closer. Its unlikely the roots from either plant will damage the house's foundation, even after decades. Ultimately, you should be safe planting at least 5' from the house for these two plants. Another thing to consider is how close these shrubs are planted to one another. You can use the same recommendation for determining distance from the house and space the shrubs 1/2 their mature spread plus 1' pending how intermingled you prefer the mature shrubs to be. For the two shrubs you are considering, you could think about spacing them at least 6 if not 7 feet apart. This way they can grow without pruning to a nice mature size and not bump into each other. If you prefer the look of a heavier prune, you could plant them closer together. Hope this is helpful! Best of luck to you!
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Prune or Transplant?
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Date Posted: Sat, Sep 12 - 1:12 am
- We have several shrubs that we planted about 3 years ago that have been thriving. I thought we had spaced everything well but they've really exploded in growth. They're all beautiful and seem healthy. We've let them get pretty wild but I am worried now that we're at the point of overcrowding. We have a Spice Girl Viburnum, a Sweet Talker Viburnum, and a Crimson Fire Loropetalum together and the Loropetalum is closest to our Flame Thrower Redbud tree. (In the pictures you'll also see Radiance Abelias but if possible, we don't want to move those as they are right along the border with our garden path). How do I decide if I just need some more intentional pruning or if it's time to move one of the plants? Which would you recommend moving? The Sweet Talker Viburnum is the one closest to the fence and there is some room to move it but is it feasible to try to shift it over if it's only a shift 6-18"? Would it be better to move the Lorapetalum? I appreciate your advice!
- Thank you for reaching out! It sounds like your shrubs are very happy in their location, which is a great problem to have! After only three years, however, they may still have quite a bit of growing to do, so this is a good time to think about their mature sizes rather than just their current sizes. Some overlap between shrubs isn't necessarily a problem, particularly if you're going for a full, layered garden. The concern is when plants become crowded enough that they are competing for light and space, developing an uneven shape, rubbing against structures or neighboring plants, or requiring frequent pruning just to keep them within their allotted area. Virginia Cooperative Extension recommends spacing shrubs according to their mature size; overcrowding can eventually reduce flowering and air circulation and create competition for resources. I would start by looking up the expected mature width of each of your specific cultivars and measuring from the center of each plant to its neighbors. This will give you a better idea of whether you're dealing with vigorous young growth that can be managed with selective pruning or plants that ultimately don't have enough room. For your viburnums, I would wait until immediately after they finish blooming next spring to do any significant pruning. Spring-flowering shrubs generally form their flower buds on the previous year's growth, so pruning them now, over the winter, or early next spring would remove many of next year's flowers. When you do prune, I would favor selective thinning and removal of individual branches rather than shearing the outside of the shrub. The goal is to preserve the plant's natural shape rather than continually making it smaller. If your measurements show that the shrubs will still substantially overlap at maturity, I would consider transplanting rather than committing to increasingly heavy pruning every year. Fall, after deciduous plants enter dormancy, is a good time to move established shrubs in Virginia. I probably would not dig up an established viburnum simply to move it 6–18 inches. For a three-year-old shrub, that's quite a bit of root disturbance for relatively little additional growing room. If 6–18 inches truly resolves the mature-spacing issue, it can be done, but I would first see whether thoughtful pruning accomplishes what you need. Of the plants you mentioned, I would pay particular attention to the Crimson Fire loropetalum's relationship with the Flame Thrower redbud. The redbud will continue developing a much larger canopy and root system, so if the loropetalum is positioned where the two will increasingly interfere with one another, moving the loropetalum to a location where it has adequate room at maturity may provide a better long-term solution than repeatedly pruning it away from the tree. Since all of the plants currently look healthy, you don't necessarily need to make an immediate change. You could use this fall and winter to measure the bed and compare those measurements with the cultivars' mature sizes, then enjoy the viburnums' flowers next spring and make your pruning or transplanting decisions from there. Also, here's a great resource for pruning: https://ext.vt.edu/lawn-garden/pruning.html
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Native Plant Options for a Challenging Urban Site
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Date Posted: Wed, Sep 09 - 2:03 am
- I'm the Business Operations Coordinator for Tribeca Kitchen & Hospitality, opening soon next to Movieland on Arthur Ashe Blvd. Attached is an image of the sandy and rocky soil in front of the building. The owner would like to just place mulch over it, but I was wondering if there was a cost effective solution using plants (even better if they're natives) that would survive and thrive in these soil conditions.
- Thank you for reaching out, and congratulations on the upcoming opening! This could definitely be an opportunity to incorporate plants rather than covering the entire area with mulch. Looking at your photo, my first concern would actually be what is underneath the sandy/gravelly surface. This appears to be a heavily disturbed site, which is common around construction. There may be compacted subsoil, construction fill, or very little actual topsoil present. Before investing in plants, we would recommend digging a few test holes to see what is beneath the surface and submitting a soil sample through Virginia Cooperative Extension. A soil test can tell you the pH and nutrient levels, while digging into the site will give you a better idea of soil depth, compaction, and drainage. The good news is that you don't necessarily need to replace everything with rich topsoil. In fact, many Virginia native plants do well in relatively lean soils, and adding large amounts of compost or fertilizer isn't routinely recommended when the plants are appropriately matched to the site. The bigger issue may be loosening severe compaction and making sure there is enough soil for roots to establish. If this area receives six or more hours of sun and drains quickly, there are a number of Virginia natives worth considering for a tough, relatively low-maintenance planting. Some possibilities include: Black-eyed Susan (Rudbeckia hirta) – cheerful yellow flowers, adaptable to challenging sites, and valuable to pollinators. It can also reseed and help create a fuller, more naturalized planting over time. Threadleaf coreopsis (Coreopsis verticillata) – a favorite option for this site because it handles sun and relatively dry conditions well and provides a long period of bright yellow flowers. Little bluestem (Schizachyrium scoparium) – another favorite for this type of location. This native grass performs well in dry, lean soils and adds height, movement, and great fall and winter interest. Butterfly weed (Asclepias tuberosa) – an excellent choice for sunny, dry, well-drained locations and an important host plant for monarch butterflies. Whorled milkweed (Asclepias verticillata) – tolerates relatively dry soil and provides additional value for pollinators. Purple lovegrass (Eragrostis spectabilis) – a native grass with airy purple-pink seed heads that can be particularly attractive when planted in groups. Common yarrow (Achillea millefolium) – adaptable, drought tolerant once established, and useful for filling spaces between larger plants. Of these, black-eyed Susan, threadleaf coreopsis, and little bluestem would be some of my personal favorites for this location. Planted together in repeating groups, they could create a simple but attractive native planting with flowers through the growing season and the little bluestem providing structure and interest into fall and winter. Rather than planting individual specimens surrounded by large expanses of mulch, I would consider mass planting a limited number of species in repeating groups. This tends to look more intentional in a commercial landscape and, as the plants mature and fill in, can reduce the amount of exposed mulch while providing habitat and food for insects and birds. You could try spreading seed this fall to help keep the project cost effective. You could also try connecting with gardeners in the Virginia Native Plant Society Group or the RVA Gardening group on facebook to see if anyone has an abundance from their yard they would be willing to share. Good luck!!
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Mosquito Management
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Date Posted: Thu, Sep 03 - 6:41 pm
- Mosquitos!!! The bane of our existence here in Midlothian VA where we have lived for the last 23 years. We love to garden and spend lots of time outside. We have tried mosquito shield spray services such as Orkin, Thermacell repellents and of course Off spray and wipes. Any hour of the day, mosquitos swarm to us. In less than 5 minutes they find us no matter what. We've also tried prevention, such as cleaning out gutters, eliminating standing water etc. Do you have reports of products or prevention that have been most effective for Richmonder's wanting to spend time outdoors in their gardens? Thanks so much!
- Thank you for reaching out! Unfortunately, mosquitoes can be especially challenging in our warm, humid Richmond-area summers, and it sounds like you have already tried many of the common recommendations. The most effective approach is generally to combine several mosquito-management strategies. You are already doing one of the most important things by eliminating standing water. We recommend continuing to check the property at least weekly, since mosquitoes can develop in surprisingly small amounts of water. In addition to gutters, look closely at flowerpot saucers, tarps, wheelbarrows, toys, buckets, birdbaths, corrugated drain extensions, trash/recycling containers, tree holes, and anywhere else rainwater may collect. Containers should be emptied and scrubbed, not just dumped, because mosquito eggs can remain attached to the sides. For water that cannot reasonably be emptied, such as rain barrels, some water features, or other areas of persistent standing water, consider using a mosquito larvicide containing Bti (Bacillus thuringiensis israelensis) according to the product label. These are commonly sold as mosquito dunks or bits and target mosquito larvae before they become biting adults. For personal protection while gardening, EPA-registered repellents remain one of the most reliable options. Active ingredients to look for include DEET, picaridin, IR3535, or oil of lemon eucalyptus/PMD. If you dislike the feel or smell of DEET products, you may find a picaridin-based repellent worth trying. You mentioned Thermacell products as well. These are a type of spatial repellent and can be helpful within a limited area, but their effectiveness can be affected by wind and the size of the area you are trying to protect. They may work better for sitting on a patio than for moving throughout a garden. One additional, simple option to try is air movement. Mosquitoes are relatively weak fliers, so placing a strong outdoor fan near a patio, gardening work area, or other place where you spend significant time can make that particular area much less hospitable to them. We would be cautious about relying heavily on routine whole-yard insecticide spraying, particularly in a garden with flowering plants. Products used to kill adult mosquitoes can also affect non-target insects. CDC guidance specifically recommends avoiding applications to plants in bloom or plants being visited by bees and butterflies. If you do choose professional mosquito treatment, we would suggest asking the company exactly what product they use, where they apply it, and what steps they take to minimize exposure to pollinators. Finally, if mosquito numbers are truly extreme despite diligent management on your property, the source may not be entirely within your yard. Nearby properties, drainage areas, neglected containers, or other standing water can continually produce mosquitoes that move into your garden. I hope this gives you a few additional strategies to try. Unfortunately, there isn't one product that will create a completely mosquito-free garden, but combining breeding-site reduction, larval control, personal repellents, and protection of the areas where you spend the most time can make a noticeable difference.
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Cherry tree dropping leaves
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Date Posted: Tue, Aug 11 - 11:37 am
- Need assistance with a cherry tree losing leaves. He did not see black spots or holes in leaves, thinks heat may be a factor.
- Thank you for contacting the Master Gardener Help Desk. Heat and drought stress can certainly cause cherry trees to lose leaves, particularly during the hot, dry conditions we've experienced this summer. When trees become stressed, they may shed older leaves to conserve water. However, leaf drop can also be caused by diseases such as cherry leaf spot, bacterial leaf spot, or other environmental stresses. Since you did not observe black spots or holes in the leaves, those diseases may be less likely, but it can be difficult to determine the cause without examining the tree and the fallen leaves. In the meantime, make sure the tree receives adequate water during dry periods. A mature tree generally benefits from a slow, deep watering when rainfall is lacking rather than frequent shallow watering. Applying a 2- to 3-inch layer of mulch around the base of the tree (keeping it several inches away from the trunk) can also help conserve soil moisture and moderate soil temperatures. If the tree is otherwise healthy and the leaf drop is due to heat stress, it should recover once environmental conditions improve. Avoid fertilizing or pruning the tree while it is under stress. If the problem continues, or if you notice spots on the leaves, dead branches, oozing bark, or other symptoms, it is likely more than an environmental problem. Photos of the entire tree, the trunk, and both the upper and lower surfaces of affected leaves would be especially helpful in narrowing down the cause. You can email photos to rvamastergardeners@gmail.com
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Reviving a snake plant
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Date Posted: Tue, Aug 11 - 11:28 am
- Hi! I am desperately trying to save this snake plant. Is there anything that can be done to return it to its former glory.
- Thank you for including a photo! The good news is that your snake plant (Dracaena trifasciata, formerly Sansevieria) appears to be alive and actively growing. I can see several healthy new leaves and offsets ("pups"), so it has a good chance of recovering. The older leaves that have fallen over will not become upright again. Once a snake plant leaf bends or creases, it will remain that way. You can prune those damaged leaves off at the base using clean scissors or pruners. This allows the plant to direct more energy toward healthy new growth. Your plant also appears to have several offsets and may be crowded in its current pot. While repotting, inspect the roots and rhizomes. Healthy roots are firm and light-colored. Remove any soft, mushy, or blackened roots, which may indicate rot, and repot in a container with a drainage hole using a well-draining potting mix formulated for succulents or cacti. If desired, the offsets can be divided and potted separately. The leaves are longer and more arching than is typical for a snake plant, which often indicates it has been growing in lower light. While snake plants tolerate low-light conditions, they develop stronger, more upright growth in bright, indirect light. Moving it to a brighter location (avoiding harsh afternoon sun) should help encourage sturdier new growth. Finally, be careful not to overwater. Allow the potting mix to dry completely between waterings, and never let the pot sit in standing water. Overwatering is the most common cause of problems with snake plants. With a little cleanup, fresh potting mix, and brighter light, your plant should continue producing healthy new leaves. It may take several months for the new growth to fill in and restore the full appearance of the plant.
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Ground Bees
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Date Posted: Tue, Aug 11 - 11:24 am
- Our lawn is infested with "ground bees." They emerge in the spring for about two weeks. They do not sting, but they are an annoyance. And they are destructive of our lawn. How can we get rid of them? Are there effective insecticides? Any help will be appreciated
- Thank you for reaching out with your question. Ground bees are solitary, ground-nesting native bees that are among the first pollinators to emerge in spring. Although they often nest in large groups, each female creates and provisions her own nest. They are generally non-aggressive and rarely sting as you mentioned, and their activity typically lasts only a few weeks before the adults disappear for the remainder of the year. During the rest of the year, the developing bees remain underground until the following spring. Because they are important pollinators, Virginia Cooperative Extension recommends leaving them undisturbed whenever possible. Ground bees prefer dry, well-drained soil. If they are nesting in an area where their presence is problematic, keeping the soil moist during their brief spring nesting period can discourage them from using that location in future years. Improving turf density through proper fertilization, overseeding, and irrigation can also make lawns less attractive for nesting by reducing areas of exposed soil. Virginia Cooperative Extension does not generally recommend insecticides for ground bees because of their beneficial role as pollinators and because their active period is so short. By the time treatment is considered, they are often nearly finished nesting for the season. If the bees are creating a safety concern in a high-traffic area, you may wish to consult a licensed pest management professional, but for most situations, tolerating them for the brief period they are active is the preferred management approach. Here are two online articles that discuss ground bees that you may find helpful: https://fairfaxgardening.org/ground-nesting-bees/ https://www.richmonder.org/ground-nesting-bees-are-a-spring-phenomenon-in-richmond/
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Watering while out of town
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Date Posted: Mon, Jul 27 - 8:28 pm
- This may seem an odd request. We are leaving our Bon Air home for a rare two-week getaway on 8/1. We are concerned about some of our bedding plants that are not irrigated. We hand water throughout the week. Do you know of anyone who might be interested in stopping by a few times to water while we are away? We are located within the City limits near Old Gun Road across from St. Edwards. Thanks for taking the question!
- Thanks for reaching out with your question! Unfortunately, we don't have a list of volunteers or services that provide watering assistance while homeowners are away. You could consider installing a simple drip irrigation system on a timer. Many affordable options are available for both in-ground beds and container gardens, and they can be a great way to keep plants watered during vacations or periods of hot, dry weather. I realize that isn't the immediate solution you were hoping for, but I hope it's a helpful idea for the future. I hope you're able to find someone to help, and that you have a wonderful trip!
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Pruning Willow Oak and planting Chicago Hardy Fig
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Date Posted: Thu, Jul 02 - 7:00 pm
- Hello, We have a very large Willow Oak tree that we want to trim. Any recommendations for arborists that can trim these large trees without causing harm to the tree? We also have a Chicago Hardy fig tree, how far from the foundation should we plant it?
- Thank you so much for reaching out to the Richmond Master Gardeners. For your willow oak, we recommend hiring an ISA (International Society of Arboriculture) Certified Arborist with experience pruning large, mature shade trees. Proper pruning is important for maintaining the long-term health and structure of an established oak, and an experienced arborist can determine whether pruning is necessary and recommend the best approach. While we aren't able to give specific recommendations, you can search for certified arborists in your area using the ISA's "Find an Arborist" directory: https://www.treesaregood.org/findanarborist. Be sure to ask about their experience with mature oaks and request proof of certification and insurance. For your Chicago Hardy fig, we recommend planting it at least 10–15 feet from your home's foundation. Although figs generally have shallow, spreading root systems that are not considered aggressively invasive, they can become quite large, often reaching 15–30 feet tall and wide under favorable conditions. Allowing adequate space provides room for the canopy to develop, improves air circulation, makes harvesting easier, and helps avoid branches rubbing against the house. If you plan to keep the fig pruned as a smaller shrub, you may be able to plant it somewhat closer, but 10–15 feet is a good general guideline for long-term growth.
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Master Gardener Classes
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Date Posted: Wed, Jun 10 - 1:28 am
- how do i sign up for classes to be a master gardener?
- Hello! Thank you so much for your interest in taking Master Gardener classes. Class information should be available later this summer with applications opening in September. Please e-mail rvamastergardeners@gmail.com to get added to our wait list to receive information once it is available.