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Declining Rose Bushes

    Date Posted: Wed, Aug 20 - 12:18 am

    Question

  • We have a row of drift roses out from for the last 8 years, last year once bush died totally after pruning and was replaced but two others appear to have dying branches in places but are blooming in others. Do you have any recommendations? They previously were huge and bloomed all summer.
  • Answer

  • Thank you for reaching out about your drift roses. After 8 years, it’s not uncommon to see some decline in vigor, and the symptoms you’re describing (a bush dying after pruning, and others showing partial dieback while still blooming) may have several contributing factors. Possible Causes Age & Natural Decline: Drift roses, while hardy, often start to lose vigor after 7–10 years. Decline in individual plants can be expected over time. Pruning Stress: If roses are pruned too severely or at the wrong time (late fall/early winter), it can stress the plant and increase vulnerability to dieback. Canker or Dieback Disease: Fungal cankers can cause branches to brown and die back while other parts of the shrub continue to bloom. Look for discolored, sunken, or shriveled stems. Root Stress: After many years in the same spot, soil compaction, poor drainage, or root competition from nearby shrubs can weaken roses. Environmental Stress: Last winter’s cold snaps, summer drought, or inconsistent watering can also contribute. Recommendations Inspect the Canes: Cut into affected stems. If the wood inside is brown rather than green/white, prune those branches back to healthy tissue. Sterilize pruners between cuts (70% alcohol or 10% bleach solution). Monitor for Pests/Disease: Check for signs of fungal cankers, crown gall, or borers. Mulch & Soil Health: Refresh mulch to 2–3 inches (but keep away from the crown). Consider lightly amending with compost to improve soil structure and nutrients. Watering Practices: Provide consistent deep watering during dry spells, especially since stressed plants are more susceptible to disease. Rejuvenation Option: If more bushes continue declining, you may want to replace them gradually. Consider rotating in disease-resistant shrub roses or other flowering shrubs to diversify and reduce the chance of future loss. Since one plant has already died and others are showing decline, you may be at the natural replacement stage for part of the row. Healthy roses can last many years, but staggered replacement every few years can keep the planting full and vibrant.

Why is my swamp milkweed dying?

    Date Posted: Thu, Aug 14 - 11:54 pm

    Question

  • I have an established butterfly bush and swamp milkweed plant in my yard. They’re both around 3ft tall. This year, both plants began dying fast. We haven’t dumped anything there, nothing changed as far as plants, soil, drainage, etc. with one exception. Three years ago we planted some Blue Mistflower. It never came up until this year. It is climbing the dead butterfly bush. I’ve read Blue Mistflower spreads via rhizomes and that this could potentially be the cause. Any thoughts? Other things I should check? Thanks!
  • Answer

  • Thanks for reaching out to the Richmond Master Gardeners! I've connected with one of our gardeners, Pam, that has a wealth of knowledge on native plants to help give you some guidance. There has been a lot of chatter in the Virginia Native Plant Society Facebook group that this has been a banner year for milkweed aphids. Swamp milkweed seems particularly susceptible to this aphid, and you truly have “a” plant (singular), it becomes the sole target for the aphids. The aphids submit a dew that causes a fungus. Unfortunately, the picture doesn’t show the milkweed clearly enough for this to be more than a guess, but we think it’s a reasonable possibility. We wouldn’t blame the blue mist flower. Yes, it’s hardy and loves to spread, but it’s a valuable late-season food source for pollinators. We recommend planting a different companion for it. You did not mention you soil or light conditions, but the Plant RVA Natives guide (download free at vnps.org) will help identify companion plants that can hold their own with an enthusiastic spreader. Pycnanthemum muticum, clustered mountain mint, might be a possibility, and it blooms much earlier, spreading the glory. Since butterfly bush is designated invasive in Virginia, we can’t ethically recommend trying to save it or replacing it with another. But its loss provides an opportunity to plant more natives. If you have additional questions about natives, Pam will be at the West End Branch of the Richmond Public Library on Wednesday afternoons after Labor Day. You are welcome to stop in and chat with her more!

Transplanting a peach tree

    Date Posted: Thu, Aug 14 - 5:34 pm

    Question

  • I need to transplant this peach tree but know next to nothing about when/how/where. Would love advice!
  • Answer

  • Thank you for reaching out! Peach trees can grow successfully in the Richmond area when given the right conditions and care. Since your tree is currently in a pot, here are some steps and tips to guide you through transplanting it into the ground: Best Time to Transplant Late fall to early spring (after leaf drop but before buds swell) is ideal. In Richmond, that’s typically November through March when the tree is dormant. This reduces stress and gives roots time to establish before summer heat. Choosing a Planting Site: Sunlight: Choose a location with full sun — at least 6–8 hours daily. Soil: Well-drained, loamy soil with a pH of 6.0–6.5 is best. Avoid low areas where water collects. Soil test kits can be found at local Richmond Public Libraries Air Circulation: Good airflow helps reduce fungal diseases. How to Transplant: Dig a hole twice as wide as the root ball and just as deep. Loosen the surrounding soil to encourage root spread. Gently slide the tree out of the pot, loosening any tightly wound roots. Trim circling roots to prevent girdling. Place the tree so the root flare (where roots meet trunk) is level with or slightly above ground level. Fill with native soil (you can mix in some compost if soil quality is poor). Water deeply to remove air pockets. Apply 2–4 inches of mulch around the base, keeping it a few inches away from the trunk. This helps conserve moisture and regulate temperature. After planting: Water deeply once a week during the first growing season, more often in hot/dry spells. Lightly prune in late winter to shape and remove damaged branches. Young peach trees can be susceptible to deer, rabbits, and voles, so consider fencing or trunk guards. Good luck with your peach tree!! We wish you lots of success! Thanks again for reaching out.

Serviceberry TLC

    Date Posted: Thu, Jul 31 - 10:56 pm

    Question

  • My service berry tree has split bark in several places and there may be insects in the bark. There are many yellow leaves. The tree doesn’t look healthy. I planted it in the fall. Is there anything I can do to save it?
  • Answer

  • Thank you for reaching out! It sounds like your serviceberry tree is experiencing some stress, but we’ll do our best to help you support its recovery. Yellowing leaves can indicate a few things: transplant shock, water stress, or even nutrient deficiency. This is common in newly planted trees as they adjust to their environment. Split bark can also be a sign of environmental stress like rapid temperature changes in winter (known as frost cracks or sunscald), mechanical injury (e.g., weed trimmers or animals), and overwatering or underwatering. Unfortunately, splits in the bark can make the tree more susceptible to insect or disease invasion. If you see insects, they may be opportunists rather than the primary cause. What You Can Do: Inspect the trunk: Look closely at any insects you find. If you can, take a clear photo to try to ID. Mulch properly: Place a 2–3 inch layer of mulch around the base of the tree (keeping it a few inches away from the trunk) to regulate soil temperature and moisture. Water consistently: Deeply water once a week during dry periods. Avoid overwatering—serviceberries prefer moist but well-drained soil. Prune carefully: Remove any obviously dead or damaged branches, but avoid heavy pruning during stress periods. Avoid fertilizer for now: Wait until the tree is more stable before fertilizing. It may take some time for your serviceberry to bounce back, but with proper care and monitoring, it could still recover. We wish you the best! For more information, check out: https://piedmontmastergardeners.org/article/serviceberry/

Amaryllis TLC

    Date Posted: Thu, Jul 31 - 11:27 am

    Question

  • I have a plant that I think is an Amaryllis (it belonged to my grandmother). It has never bloomed and the stems are very droopy. Do you have suggestions for how to care for it and encourage it to bloom? Or is it a different plant? Thank you!
  • Answer

  • Thank you for your question—and how special to have a plant that belonged to your grandmother! From your photo, it does appear to be an amaryllis, especially given the long, strap-like leaf. If it's never bloomed and the foliage is droopy, a few adjustments in care might help encourage healthier growth and eventually, blooms. Here are a few tips to support your amaryllis: Light: Amaryllis need bright, indirect sunlight to thrive. If it's indoors, try placing it near a sunny window. Without enough light, the leaves may become elongated and floppy. Watering: Water sparingly—the bulb doesn’t like to stay soggy. Water when the top inch of soil feels dry, and make sure the pot drains well. Potting: Make sure the bulb is planted in well-draining soil and that about one-third of the bulb remains above the soil line. A snug pot is best—just about 1 inch wider than the bulb. Bloom Encouragement: Amaryllis often need a dormancy period to bloom. In late summer or early fall, you can: Stop watering and allow the leaves to die back naturally. Move the pot to a cool, dark place (around 50–55°F) for 6–8 weeks. After the rest period, bring it back into the light, resume watering, and it should begin new growth—with a bloom soon to follow! We hope these suggestions will help you enjoy a happy, blooming amaryllis for years to come!

Preparing new garden beds for planting

    Date Posted: Tue, Jul 15 - 10:50 pm

    Question

  • I need to landscape front garden beds. what’s best to place on top of area for two months. Are tarps weighed down w/bricks okay? Arborist chips clean? I’m old so I want something easy/low maintenance. Planning on native perennials and grasses, a few shrubs/service berry.
  • Answer

  • Thank you for your question! It sounds like you're off to a great start with a thoughtful plan for a low-maintenance, native landscape. Both of the options you suggested are great ideas for prepping your beds for planting. 1. Tarps: Yes, tarps weighed down with bricks or secured with lawn staples can work well to smother weeds and prevent new growth before planting. This method is known as "occultation." It’s easy, effective, and doesn't require much labor. Just make sure the tarp is opaque and tightly secured to prevent wind from getting underneath. I have personally had success with using black plastic and lawn staples, and am able to re-use the black plastic when I'm ready to expand the garden. 2. Arborist Wood Chips: Fresh arborist chips are also a great option, especially for a native planting. They help suppress weeds, retain moisture, and gradually improve soil as they break down. It’s fine to apply them now even if they’re “green” (fresh)—just keep them 3–6 inches deep and avoid piling them right against any existing stems or trunks. You can combine both methods too: tarp the area now, then remove the tarp and add arborist chips once you’re ready to plant. Native perennials, grasses, and a few shrubs like serviceberry are perfect choices for a low-maintenance, pollinator-friendly garden. Once established, they should need minimal watering and upkeep. Happy gardening!

Indoor Bamboo

    Date Posted: Thu, Jul 10 - 12:16 am

    Question

  • My bamboo leaves has brown tips. It is potted inside my home in dirt. It's not in direct sunlight and I water once every other week. I wonder if the tap water had too much fluoride. Please advise.
  • Answer

  • Thank you for your question about your indoor bamboo plant! Brown tips on bamboo leaves are a common issue and can result from a few different factors. Based on your description, here are some possibilities to consider: 1. Water Quality (Fluoride or Chlorine) You're right to wonder about your tap water—bamboo can be sensitive to fluoride, chlorine, and other chemicals commonly found in municipal water. Over time, these can build up in the soil and damage the leaf tips. To help with this: Try using distilled water, rainwater, or water that has been left to sit out for 24–48 hours (which allows chlorine to dissipate). You can also occasionally flush the soil with clean, non-fluoridated water to help remove any buildup. 2. Low Humidity Indoor air—especially with heating or AC—can be quite dry. Bamboo prefers higher humidity levels. Mist your plant regularly or place a shallow tray of water and pebbles beneath the pot to increase humidity. Grouping plants together can also raise the local humidity level. 3. Underwatering Watering once every other week may not be enough, depending on your home's temperature, humidity, and the plant's container size. Brown tips can be a sign of inconsistent moisture. Try checking the soil weekly. If the top inch is dry, it's time to water. Bamboo likes consistently moist (but not soggy) soil. 4. Light Levels While bamboo doesn't need direct sunlight, it does need bright, indirect light to thrive. If your plant is in a very low-light spot, consider moving it closer to a window with filtered light. 5. Salt or Fertilizer Buildup Over time, salts from tap water or fertilizer can accumulate in the soil and damage roots. If you've been fertilizing, consider cutting back and flushing the soil with clean water occasionally. Hope these ideas will help you out!

Bitterness in Cucumbers

    Date Posted: Tue, Jul 01 - 1:28 am

    Question

  • I'm growing cucumbers for the first time this year, and so far have only harvested a few. They are heirloom straight 8 cucumbers I started from seed. I'm harvesting them at about 6 inches long. I cut the ends off when I slice them to avoid bitterness, but they still seem to taste quite bitter and soapy. I'm not spraying them with anything, and I was them well with water when I harvest them. What might be making them bitter?
  • Answer

  • Thanks for reaching out to the Richmond Master Gardeners! Bitterness in cucumbers—especially heirloom varieties like Straight 8—is a fairly common issue, although frustrating, and it’s usually due to the natural compounds called cucurbitacins. A few reasons you might be experiencing bitterness: First off, we have to think about environmental stress, especially given the extreme heat and big down pours we have been having. Cucurbitacin levels tend to rise when the plants are under stress and common stressors for cucumbers include: Inconsistent watering (periods of drought followed by heavy watering), high temperatures, and also poor soil fertility or nutrient imbalance. Straight 8 cucumbers tend to be prone to bitterness, especially in hot and dry conditions. Try to keep soil moisture even by watering regularly (especially during hot spells), and consider using mulch to conserve moisture and keep soil temps steady. There's a chance your cucumbers are sitting on the vine a little too long and getting a little overripe. If you notice any yellowing of the skin or a hard waxy exterior, they are likely getting a little too ripe. You could try harvesting a little sooner, maybe when they are 5 inches, to see if that helps. As you already seem to know, the bitter components are most concentrated at the the stem end, in the skin and just under the skin. In addition to trimming the end of off, you could try peeling the cucumbers. I've also heard of people soaking them in cold salted water for about 40 minutes once they are peeled. I haven't tried this myself, but I've heard it helps to reduce the bitterness. Their are some hybrid varieties that are bred to reduce bitterness. If none of the above ideas help you to reduce bitterness, you could try growing a hybrid variety next time and see if that helps. Good luck! We hope you are able to enjoy your cucumbers!

Hydrangea Pruning

    Date Posted: Wed, Jun 04 - 1:52 am

    Question

  • 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!
  • Answer

  • 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.

Rhododendron Questions

    Date Posted: Thu, May 08 - 11:14 pm

    Question

  • 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
  • Answer

  • 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!