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Frequently Asked Questions

Do you have ‘grass patches’ that grow twice as fast as your turf during the summer, even during the hottest weather?  You likely are combating yellow nutsedge, a common warm-season lawn weed across Virginia. (read more)
The azalea lace bug is the most frequently reported insect pest in the landscape. (read more)
Moles and voles are indeed a lawn and garden pest. However, wild animals are part of what makes nature so magical. While it’s important to coexist with animals in relative peace, they can cause problems when they live in our lawns and gardens.(read more)
You have to identify your weed before you attempt any type of control. You can find a comprehensive resource on weed ID  and control from the University of Kentucky Extension.
There are 3 methods: (1) dig out the rhizomes and runners (2) mow it down for 2-3 years each time you mow the lawn, and (3) Cut to the base in winter, in spring when the foliage is 3′ tall, spray foliage with Glyphosate, repeat 4-5 times (may take 4-5 years) (read more
 The best time for hydrangea transplanting is just after the bushes have gone dormant in the autumn. This means the flowers have all died back and most, or all, of the leaves have dropped. In climates where the ground doesn’t freeze, you can do your hydrangea transplanting between December and February. (read more
When necessary, prune in the spring after flowering so as not to reduce flowering the next spring. 
Some plants thrive in wet areas, for example: Iris, Coral Bells, some Ferns, Hellebores, Mint, Wood Sorrel, Myosotis (Forget‑Me‑Not), Mountain Laurel, and Evergreen Bayberry. 
Moss likes shade, moist soil, acidic soil, and compacted soil. Do a soil test to see what you can do to change the pH of the soil to make it less acidic. Aerate the soil to loosen compaction. (read more)
It’s probably due to overlapping of fertilizer. Double application may “burn” the roots. 
Cut them back by a third, clean up the leaf litter, use a soaker hose rather than overhead watering, and spray with Neem oil. (read more)
Wait until the fall when plants have died back. Then, remove spent flowers, dead leaves, and stems. If they’re still green, they are feeding their roots and need to keep going.
Wear protective clothing and cut out a one-foot section of the vines all around near the bottom of the tree. The vines above will wither and die off. (read more)
Prune azaleas right after they bloom in the spring. Prune roses in late winter just as tiny buds begin to show. (read more)
Wear protective clothing and eye protection, and paint freshly cut stump with glyphosate (eg. RoundUp). This is a slow process and you may have to reapply.
You should talk to a certified arborist. It’s not likely that cutting a few roots on one side would kill the tree, but the tree may continue to put out roots on that side anyway.
These symptoms indicate the plants are having trouble drawing water up through the roots. Dig up one plant to see if the roots are healthy.
Unfortunately, you must dig up the entire plant and roots and dispose of it in the trash. Any shrub except rose can be planted in that spot, as the virus that caused that disease remains in the soil for a while. (read more)
The boxwood blight pathogen can persist in the soil for 5-6 years. Virginia Tech Extension has a list of “most resistant” varieties you can replace it with. (read more)
 Liriope (aka Lilyturf, Monkey Grass) needs to be cut/mowed down to the crown in late winter (think Washington’s Birthday) before the new growth gets 1″ tall.
Moles are after grubs, the larvae of Japanese beetles. To get rid of moles, get rid of the grubs by applying a grub treatment product on your lawn in mid-summer. (read more)
Selecting appropriate planting dates is a critical component of successful vegetable gardening. Vegetables vary widely in their preferred growing conditions and tolerance to temperature extremes, both cold and hot. Please refer to Virginia’s Home Garden Vegetable Planting Guide: Recommended Planting Dates and Amounts to Plant.
Figs require a soil pH of 6 – 6.5. The soil may have become too acidic over the years for fruit production. It would be best to obtain a soil sample and have it evaluated. For more information on soil samples, see this document from the University of Maryland Extension.
These crown galls often affect euonymus and forsythia. There is no chemical treatment. We suggest cutting out the galls. If there are too many, remove the entire plant and do not re-plant the same kind of plant in that space as the bacterium that caused the galls will remain in the soil for 4-5 years. (read more)
Aerate first, then shortly thereafter (within a week) you can put the seed and fertilizer down at the same time. SMART Lawns is designed to help you follow a custom program for caring for your own lawn.
Peach pits need to be prepared in advance of planting. The seeds of all common tree fruits (apple, pear, peach, and cherry) require a chilling period before they will germinate and form new plants. There are three common means of propagating which are described in this article from Penn State Extension.
It’s a good idea to plant “green manure” in the fall to add organic matter, hold nutrients, and reduce erosion. Till it under in the spring. Wait three weeks before planting or seeding any new crops. (read more)
One thing that is almost always NOT recommended or warranted for home lawns is a chemical fungicide application. These soil-borne fungi are almost impossible to control with even the most active fungicides, and the best option to deal with their fruiting bodies is to simply mow them or drag them with a garden hose. More information can be found in this article from Virginia Tech Extension, that has an accompanying PDF document on the subject.
This is most likely the result of an infestation of one of these pests: oak borer, longhorned beetle, or roundheaded borers. The best time to treat is May-July. Read more about these pests on shade trees and how to treat them.
It is probably cercospora leaf spot, a common disease on many ornamental plants. Recommendations are to practice good clean-up and sanitation, use a soaker hose instead of overhead watering, apply fungicide appropriate for cercospora leaf spot in early spring — it’s not effective to cure already affected parts of the plant. Treat every 10-14 days while new growth is emerging. This disease is usually cosmetic and rarely kills the plant. In the future, you may want to select varieties that are resistant.
In severe outbreaks, Eastern tent caterpillars (aka bag worms) can defoliate entire trees. For those who are not squeamish, heavy gloves can be worn to rip out the developing tents with their caterpillars. If spraying is essential, use Bt (Bacillus thuringiensis) as soon as the silk tents are observed in early spring. It is a natural insecticide that only affects caterpillars. Bt is harmless to humans and animals. It must be sprayed on leaves the caterpillars will eat. Bt must be used in April since only young caterpillars are highly susceptible to this insecticide. It is available under many trade names including Thuricide, Dipel, Caterpillar Attack, Biotrol, etc. (read more)
If any pesticides have been sprayed anywhere around the outside of your house, it may be because there is a lack of pollinators near your squash plants. You can manually pollinate the flowers with a small, soft paintbrush. Check out other tips in this brochure from Virginia Tech Extension on growing cucumbers, melons, and squash.
Hydrangeas need little pruning other than removing any dead wood or shortening a wayward branch. If you must: Oakleaf hydrangea: summer. Smooth hydrangea: winter. Panicle hydrangea: winter. Mountain hydrangea: summer. Once-blooming French (aka bigleaf) hydrangea: summer. Reblooming French hydrangea: summer or winter.
Mosquitos lay their eggs in standing water, so look for standing water around your property: rain barrels, gutters, upturned magnolia leaves, flowerpot saucers, kiddie pools, birdbaths (change the water frequently), low areas in pavement, water dripping from a hose, watering cans, etc. In the meantime, try to attract birds to your yard, and they will feast on the mosquitos.
Brown patch – Rhizoctonia blight – is a lawn fungal disease that is exacerbated by high nitrogen applications and wet, warm conditions. This is an opportunistic pathogen that thrives under the right conditions. Grasses will recover on their own once conditions improve. (read more)
For permanent raised beds, native mineral soils amended with small amounts of clean sourced, well-rotted composts can often provide an ideal growing medium for plants. Soil organic matter content of 3–5% is usually considered “high” for native mineral soils, and more than 10% is not recommended for garden use. You can, however, add 1-2″ of mulch on top of your bed to discourage weeds and keep the soil moist. (read more)
Pruning has been called “one of the best, worst maintenance practices” performed on trees. The process creates wounds, which have a major impact on plant processes. Improper cutting on a tree causes severe damage or even death. To prune properly, it is important to understand both the proper techniques and how the tree responds to pruning. (read Tree Pruning Essentials)