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Hydrangea Pruning
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Date Posted: Wed, Jun 04 - 1:52 am
- Hello! My hydrangeas need some help. I inherited them with my new to me house in late fall, so this spring was my first opportunity to prune. They were already overgrown from the past owners. For the big leaf hydrangeas: I missed the fall pruning, so these haven't had a haircut since who knows when. The branches are getting weighed down from the weight of the flower and leaves, and the plant is very leggy. Should I try and start selectively and slowly clipping them back now or wait until they're done blooming and do it one big chop? If now, do I cut the old leggy wood back, or just the new green branches that are stemming from the old leggy wood (the two blooms on the top of the left bush are an example)? For the panicle hydrangea in the middle: I cut what I thought was way back this spring, but clearly not enough! Should I be trying to selectively trim some of this back now or bite the bullet and wait until spring and do a big chop? It's so tall and it's only May! Thank you!
- Thanks for reaching out—and congratulations on your new home and garden! It sounds like you’re giving your hydrangeas some thoughtful attention, which they’ll definitely appreciate. The blooms are beautiful! Here’s a breakdown of how to approach pruning both your bigleaf hydrangeas (Hydrangea macrophylla) and your panicle hydrangea (Hydrangea paniculata): Bigleaf Hydrangeas : These bloom on old wood, meaning the flower buds for this summer formed last year. That’s why heavy spring pruning can often result in fewer blooms. Since yours are blooming now, I'd recommend that you hold off on major pruning until after they finish flowering—typically by mid to late summer. Then you can: Remove about 1/3 of the oldest, leggiest stems at the base to encourage new growth from the bottom and lightly shape the plant by shortening stems that look untidy or weighed down. Avoid pruning after August, however, as that risks cutting off next year’s flower buds. In the meantime, if any branches are flopping badly or blocking paths, you can do a light, selective trim now—just avoid heavy cuts that remove flower buds. Panicle Hydrangeas: These bloom on new wood, so you have more flexibility with timing. You’re absolutely right that they can grow quickly in spring! For now, you can lightly thin or shorten a few of the tallest stems to maintain a more manageable shape but avoid cutting more than 1/3 of the plant this time of year. If it’s still too tall for your space, plan for a more significant structural pruning next late winter/early spring, before new growth starts. General Tips: Always cut just above a pair of healthy buds or a leaf node. Use clean, sharp pruners to avoid disease. Consider adding mulch and checking soil drainage if plants look stressed or leggy—bigleaf hydrangeas especially like evenly moist (but not soggy) soil.
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Pruning a dwarf apricot tree
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Date Posted: Thu, May 08 - 11:20 pm
- We have a dwarf apricot tree in our backyard near our privacy fence (designated by purple arrow in photo). Unfortunately, one of the medium size limbs at the top has stretched over our privacy fence into our neighbor’s yard. I want to but the limb but I’m nervous about damaging the tree since it’s spring time. Would it be okay to cut it at this time of year?
- Thanks for your question about pruning your dwarf apricot tree. It’s totally understandable to want to manage the limb growing into your neighbor’s yard, and you’re right to think carefully about timing. While late winter or early spring (before bud break) is generally the best time to prune apricot trees, light or selective pruning—even now in late spring—is okay, especially if it’s necessary to maintain boundaries or reduce potential damage. Just keep a few tips in mind to minimize stress on the tree: -Use clean, sharp tools to make a clean cut just outside the branch collar (the slightly swollen area where the limb connects to the trunk or larger branch). -Avoid removing more than 10–15% of the tree’s total canopy during the growing season. -Try to prune on a dry day to reduce the risk of fungal infections entering the fresh cut. If you only need to remove one medium-sized limb, your apricot tree should tolerate it well—especially if it's otherwise healthy. Make sure to monitor the tree through the season for any signs of stress (like leaf drop or dieback) and water consistently during dry spells.
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Rhododendron Questions
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Date Posted: Thu, May 08 - 11:14 pm
- I have an established rhododendron and a couple of questions 1. Some leaves tern yellow and die and fall off 2. Others show yellowing but remain 3. New shoots form at the base but die never to mature 4 is there any way to encourage new growth on the old branches
- Thanks for reaching out with your rhododendron questions! You’ve made some great observations, and your plant is definitely trying to tell you something. Here are a few possible explanations and tips based on what you described: Yellowing and Leaf Drop: Some yellowing and leaf drop is normal, especially for older inner leaves. However, widespread or early-season yellowing in Richmond can also point to stress from heat or underlying root issues, particularly since rhododendrons are naturally cool-climate, understory plants. Our warm springs and hot summers can make them more susceptible to systemic diseases or environmental stress. Persistent Yellow Leaves: This could be a sign of sun stress—rhododendrons prefer morning sun with dappled afternoon shade. Too much direct, hot afternoon sun can cause the kind of yellowing you're seeing. Poor drainage or soil that’s too alkaline can also cause nutrient uptake issues, leading to chlorosis (leaf yellowing). New Shoots Dying Back: When new shoots at the base fail to mature, it often points to root zone stress, such as poor drainage, fungal root diseases, or heat stress. Check that mulch isn't piled too high against the base and that the soil is staying moist but not soggy. Encouraging New Growth on Old Branches: Yes! Light pruning in early spring, just after flowering, can stimulate new growth. Avoid heavy pruning all at once; instead, gradually thin out leggy or unproductive branches over time. Make cuts just above a healthy bud or leaf whorl to encourage branching. Good luck with your rhododendron!
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Growing Elderberries
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Date Posted: Sat, Apr 12 - 12:43 pm
- Hello! I was just gifted a native elderberry and I'm looking for some advice. I also plan to get another one so they can bear fruit. I've been watching tons of videos but they all seem contradictory! I live in Richmond (Battery Park) with an urban yard - it's a bit bigger than typical row house size, and bordered by a shared fence on each side. I have a few areas to plant the elderberry where it will get at least 8 hours of full sun a day. My concern is that I want to keep the bush somewhat contained - I know they can grow quite large, but is there a way to prune it so it stays under 7-8 feet but still bears fruit? And, do you have any advice on how to stay on top of root suckers? I'm not sure how far the suckers will travel, but if they head into my neighbors yard I obviously wouldn't be able to see the sprout to know where to cut the root. I also heard the roots are quite hardy, so I'm trying to consider whether to plant near a retaining wall. In the videos I'm watching the plants all seem pretty naturally contained (versus something like blackberry which gets out of control), but I want to do everything I can to help out. Hoping I can make this work! I appreciate any advice you have. If helpful, I can send a photo of my backyard. Thank you, Julie
- What a lovely gift! I hope this will be something you are able to enjoy for years to come. And you are right! You will need a second one for cross pollination. We don't typically think of elderberries being wildly invasive, so I'd expect with your awareness of the need to keep an eye out for suckers, and your desire to prune it to keep it at a reasonable size, you will be pleased with your elderberry. A couple of pruning tips: Once the plant is established (after year 1 or 2), you can cut back about 1/3 of the oldest stems to the ground each year to encourage new growth. To keep overall height in check, you can also cut the remaining stems back to your desired height (just above strong buds). Many gardeners cut stems to about 3–4 feet in early spring, which results in a bush that finishes around 6–8 feet tall by summer. Managing suckers: You’re right—elderberries do sucker from the roots and can spread over time, though they are usually less aggressive than blackberries. The suckers typically emerge within a few feet of the main plant, though they can travel farther in ideal conditions. To manage them, check around the base of the plant regularly during the growing season and cut suckers at the soil line or dig back to the root and clip at the source. You might also consider planting your elderberries in a root barrier ring—digging a trench and installing landscape edging 12–18" deep around the planting area to contain the roots. Planting near a retaining wall: Elderberry roots aren’t known for damaging structures like a retaining wall, but they are persistent. If you're concerned about suckers creeping into a neighbor’s yard or through shared fences, planting 3–5 feet away from those boundaries is a good buffer. That space also makes it easier to walk around the plant and manage pruning or harvesting. Hope this helps as you decide where to plant! Best of luck to you! Hope you will enjoy your elderberries for years to come.
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Tree Girdling
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Date Posted: Tue, Oct 08 - 11:35 pm
- I have what appears to be a very intense girdling root situation happening with my ruby red falls (red bud cultivar). The top of the tree died off entirely this year so I cut the dead part off (about 1 ft) earlier in the spring and just now decided to check the roots. It did produce a lot of leaves and appears to be in just ok health, but is not thriving by any means. Is this tree salvageable? Any suggestions?
- Thanks for reaching out to the master gardeners for help with your tree. I've sent your photo to a handful of other master gardeners in our group so that we can have a few opinions to share with you. Overall, we do not see serious concern for girdling in the photo that you sent. If you are seeing girdling that we can not see (maybe on the other side of the tree) you could always cut those roots away taking care to not cut into the stem/trunk of the tree. Your heavy pruning of the tree earlier this year could certainly be a cause of the abnormal growth you saw this year. From your photo, it does appear that your tree may have been planted too deep. You could pull a lot of the soil back from the tree in order to create a more shallow planting and see if this helps to improve the health of your plant. If ultimately the tree does not survive and you are looking to replace it, we would recommend going with a straight species like Cercis canadensis (Eastern Redbud)
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Blueberries and Lavender
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Date Posted: Tue, Aug 27 - 11:37 pm
- Hello, I have 3 questions - I have blueberry bushes that were not properly tended to over the summer heat. They produced lovely berries but since have grown scraggly and I need to trim them back. Is there a proper time and way to do this? I have attempted several times to take cuttings and start new plants. Failed every time. Any suggestions? I have lavender plants in front of the blueberry bushes. They are half alive and half dead. Do I need to move them? I am thinking it is from the overgrowth of limbs from the blueberry bushes but not certain. I am presently in the tedious process of soaking the ground in the evenings and pulling the grass and weeds that surround them. I appreciate your help.
- Thanks for reaching out to the Richmond Master Gardeners! You have several great questions that we will do our best to give you some guidance on: 1. When to prune blueberry bushes: The best time to prune blueberries is in late winter or early spring, just before new growth begins. This timing helps the bush recover and grow new shoots for the coming season. You could also have done some light pruning after harvesting, particularly if you noticed any dead or diseased branches. Regular, light pruning is usually better than infrequent, heavy pruning. Always make clean cuts and avoid leaving stubs, as these can become entry points for pests or diseases. 2. How to prune blueberry bushes: Start by cutting out any dead, damaged, or diseased branches. This helps improve air circulation and reduces the risk of pests and diseases. If the bush is very dense, selectively remove some of the older, thicker branches from the center of the plant to improve airflow and light penetration. This encourages better fruit development. Blueberry bushes produce the most fruit on new growth. Cut back older branches that are more than 6 years old to promote the growth of new, fruitful shoots. Aim for a well-rounded shape, which helps the bush maintain balance and supports better fruit production. Trim to keep the bush to a manageable size and shape, typically removing no more than a third of the plant's height in one season. During the growing season, you can also trim any overly vigorous shoots that might be crowding the plant, encouraging a more balanced structure. 3. Using cuttings to start new plants: The best time to take blueberry cuttings is from late summer to early fall when the wood is semi-hard but not yet fully mature. Choose cuttings from healthy, vigorous plants. Look for shoots that are not too old or too young. Ideally, the cuttings should be from the current season's growth and about 4-6 inches long. If possible, select shoots that haven't flowered, as they will have more energy to put into growing roots. - Preparing Cuttings: Make a clean cut just below a node (the point where leaves attach to the stem). This is where the roots are most likely to develop. Strip off the lower leaves, leaving a few at the top. This reduces moisture loss and encourages root growth. Although optional, dipping the cut end in rooting hormone can improve the chances of successful rooting. Rooting hormone is available in powder, gel, or liquid form. -Planting: Use a well-draining rooting medium like a mix of peat moss and perlite or sand. You can also use a commercial rooting mix. Insert the cuttings into the rooting medium about 1-2 inches deep. Firm the soil around them to ensure good contact. -Care: Keep the rooting medium consistently moist but not waterlogged. Water the cuttings gently to avoid displacing them. Cover the cuttings with a plastic bag or place them in a greenhouse or a propagation chamber to maintain high humidity. Ensure the cover does not touch the cuttings to avoid mold. Place the cuttings in a location with bright, indirect light. Avoid direct sunlight, which can be too intense for young cuttings. -Transplanting: After about 8-12 weeks, check for root development by gently tugging on the cuttings. If you feel resistance, roots have formed. Rooting can take time, so be patient and avoid disturbing the cuttings too soon. Once roots are established, transplant the cuttings into small pots with a potting mix suitable for blueberries or a mix of peat and perlite. Gradually acclimate the young plants to outdoor conditions by exposing them to more light and outdoor temperatures over a couple of weeks. 4. Caring for lavender plants: Lavender plants can be a bit finicky, but several common issues could be causing them to struggle or die. Here are a few things to think about: Lavender needs well-draining soil. Heavy, clayey, or waterlogged soils can lead to root rot. Consider improving drainage by adding sand or gravel to the soil, or planting in raised beds or containers with good drainage. Lavender prefers slightly alkaline to neutral soil, ideally with a pH between 6.7 and 7.3. You can test your soil’s pH with a kit and amend it if necessary. Lavender is drought-tolerant and doesn’t like to sit in wet soil. Water sparingly and allow the soil to dry out between waterings. Overwatering can cause root rot and other issues. While lavender prefers less frequent watering, it still needs some moisture, especially in hot, dry conditions. Ensure it gets enough water during prolonged dry spells. Lavender requires full sun to thrive, which means at least 6-8 hours of direct sunlight each day. If it’s not getting enough light, it can become leggy and weak. Lavender generally prefers temperate climates. Extreme cold or heat can stress the plant Lavender doesn’t need a lot of fertilizer. Fungal diseases like root rot, powdery mildew, and rust can affect lavender. Ensure proper spacing for air circulation and avoid overhead watering to reduce disease risk. Lavender benefits from regular pruning to maintain its shape and health. Prune after flowering to remove spent blooms and encourage new growth. Avoid cutting into old, woody stems, as they may not regenerate. Blueberries and lavender can be successfully planted together, but there are a few things to think about to ensure both plants thrive. Both blueberries and lavender prefer acidic to neutral soil. Blueberries thrive in a pH of 4.5 to 5.5, while lavender prefers a pH of around 6.7 to 7.3. This difference in pH requirements means you’ll need to find a balance or be prepared to amend the soil appropriately. Both plants need full sun to grow well. Ensure they receive at least 6-8 hours of direct sunlight each day. Both plants require well-draining soil. Blueberries are prone to root rot in poorly drained soils, and lavender, though drought-tolerant, also dislikes wet feet. Blueberries need consistent moisture, especially during the growing season, whereas lavender prefers drier conditions and is more tolerant of drought. Overwatering can lead to issues for both plants, so careful watering practices are necessary. We hope this will give you some guidance for moving forward. Happy gardening!
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Rust on serviceberry
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Date Posted: Wed, May 01 - 1:12 am
- Our serviceberry (about two years old) has a rust on the berries. It looks relatively minor (about half the berries are about 50% covered in the rust spores). We planted this tree specifically to support the birds with the berries, although we are also very happy with all of the other ecological benefits the tree provides. Will the rust effect the desirability of the berries to the birds? Is there anything we can or should do to protect the tree/berries from more rust? We live in Churchhill on a tiny urban plot - the serviceberry is our only tree. Thank you!
- Cedar-apple rust and related rust fungi need plants from two plant families to complete their life cycle; Cupressaceae family (eastern red cedar and other junipers) and Rosaceae (apple, hawthorn, serviceberry). It seems likely there must be an eastern red cedar or juniper nearby, even though you do not have any other trees in your yard - the fungal spores can travel up to two miles! This can make it difficult to control the rust. You can prune and remove infected twigs and branches and dispose of them in the trash (not compost). Be sure to decontaminate pruning tools between cuts by dipping them for at least 30 seconds in 70% alcohol (e.g., rubbing alcohol) or 10% bleach. Alternatively, you can spray tools with a disinfectant that contains approximately 70% alcohol, then allow them to air dry. Decontaminating tools will prevent movement of rust fungi from branch to branch or from plant to plant during pruning. If you are able to find nearby juniper and red cedar trees and have neighbors that are willing to help with the cause - in late winter or early spring you can prune and remove brown, woody galls found before orange, gelatinous structures that form in the spring. This will help reduce the level of infection on nearby Rosaceae plants like your serviceberry. Fungicides are not recommended since serviceberries are a resource for wildlife, birds and bees. Your question about serviceberries with rust being less desirable to the birds is challenging. It is recommended that people do not eat serviceberries affected by rust. I have read both that rust does not effect wildlife and that birds will naturally avoid berries with rust. My inclination is to think that the birds would not be interested in the berries affected by rust but I would be curious to know if you have seen a decreased bird population around your serviceberry since you started noticing the rust. I know that things like rust can be frustrating to deal with, especially given your goals with this plant. I wish you the best!
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Browning Dwarf Arborvitae
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Date Posted: Wed, Oct 11 - 12:47 am
- Dwarf Arborvitae has brown sections, on am effort to cut them out, it appears black underneath. What is happening? Thank you.
- 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!!
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Japanese Spirea
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Date Posted: Tue, Oct 10 - 5:24 pm
- 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?
- 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!
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Removing Kudzu
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Date Posted: Thu, Jul 27 - 12:13 am
- What can be used to get rid of the Kudzu that has taken over the Camellia bush?
- 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!