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Fig & Cherry trees
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Date Posted: Fri, Sep 06 - 11:33 am
- Planted two fig trees (brown Turkey, Hardy Chicago) and a cherry tree (sweetheart) in mid July that have really been struggling recently. I’m wondering what diseases they might have and would love advice on how to treat them. Thank you! Hardy Chicago fig picture attached
- Fig and cherry trees can be a bit sensitive to grow, especially when planted in the heat of summer. The best time to plant is typically in May, or if you are eager to get them in the ground you can plant larger saplings in the fall. Thank you for including the picture, its helpful to see what you are seeing. It's possible the browning you are seeing is related to environmental stress (transplanting, summer heat, etc). However, it also seems likely that your plant is suffering from fig rust, a common issue for fig trees that is caused by a fungal pathogen that can impact the health of the tree if not managed properly. Fig rust symptoms are worse during hot, wet, humid weather in late summer. Fig rust starts out as small, yellowish or reddish spots on the upper side of the leaves. As the disease progresses, these spots may turn brown and become surrounded by a yellow halo. On the underside of the leaves, you may see small, rust-colored pustules, which contain the fungal spores. Fig rust is caused by the fungus Fusicladium effusum. This pathogen thrives in warm, humid conditions and can spread rapidly if the environment is favorable. There are a few things you can do to try to control the fungus from a cultural standpoint that focus on reducing the time that leaves are wet in order to stop spore germination and infection. This includes: avoid overhead irrigation and water at the base of the plant instead, do not plant the trees in shady areas, regularly weed to help keep humidity around the tree lower, and avoid planting in areas that flood or have free-standing water after rainfall. It's also important to remove and destroy any downed leaves from near the plant to remove the fungus.
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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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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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Maples for Urban Landscaping?
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Date Posted: Thu, Sep 28 - 12:43 pm
- 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?
- 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!
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Stunted vegetable garden
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Date Posted: Sat, Aug 12 - 6:55 pm
- 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.
- 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!
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Ilex glabra-Inkberry
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Date Posted: Thu, Apr 20 - 8:37 pm
- 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!
- 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.
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Camellia Pruning
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Date Posted: Thu, Mar 02 - 4:57 pm
- 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!
- 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!
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Peonies
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Date Posted: Mon, Dec 05 - 4:49 pm
- 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
- 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!
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Powdery mildew?
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Date Posted: Fri, Oct 07 - 7:05 pm
- 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.
- 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!