Digginí In: Fall gardening tips from the masters

September 28, 2015

Virginiaís 5,000 Master Gardeners help residents garden smarter, safer and more successfully. Organized statewide in 62 units, they dispense priceless help through educational and how-to workshops, telephone helplines, Facebook pages, gardening festivals, demonstration learning gardens and plant sales. Events are often free, or a nominal fee is charged.

Here are some helpful fall gardening tips from one of the Virginia groups:

Plant now. Fall is the ideal time to plant new trees, shrubs and perennials or transplant existing plant material because the weather is cooler, roots continue to grow and there is no worry about soil drying out quickly. Fall planting allows carbohydrates produced during the previous growing season to go to important root growth because there is little food demand for the plantís top growth.

Prepare properly. Dig a hole a foot wider than the circumference of the root ball and the same depth as the root ball. If the plant is coming out of a pot, take your fingers and try to loosen some of the roots so they will continue to grow outward instead of in a circle the shape of the pot. Set it out in the middle of the hole. All plants are coming from the nursery now planted in mulch rather than soil. It is best to remove as much of that as you can because it will dry out the roots faster. Then continue to back fill with the soil you just dug out. We no longer recommend adding additives to the soil unless you have really bad hard clay soil. It is also good to make a two- or three-inch collar of soil around the roots to hold water. Water slowly and well to get rid of any air pockets in the soil and to settle the soil around the roots. Then apply two to three inches of mulch, making sure that you do not push the mulch up around the stems.

Fall gardening problems

Bagworms. Seen particularly on junipers, yews and Leyland cypress, hand pick bagworm cocoons hanging off trees and shrubs in winter and put them in a bag and dispose of them. Each casing has 1,000 eggs in it ready to hatch out in spring. Next spring, spray the infected plant with any systemic pesticide to catch the crawlers when they emerge.

Scale. Timing is everything in spraying for this problem. First, you have to identify which kind of scale you have because there are many species of this insect, which is covered by a tan, brown or whitish shell-like covering.

Galls. This abnormal deformity on leaves or stems is caused by mites, gall midges or wasps; they will not harm your plant and may or may not be back next year. These can just be cut off and disposed of in the trash.

Fire blight. This bacterial disease, which creates a blackened, shrunken, cracked or scorched by fire look, should be cut out as soon as you see it. Make a cut eight to 12 inches back into good wood and put it into a plastic bag and dispose of it in the trash. You also need to sterilize loppers so you donít spread the disease to other susceptible plants.

Invading insects. Bugs that colonize and may come in your house ó multicolored Asian ladybeetles, boxelder bugs and brown marmorated stinkbugs ó can be a nuisance but cause no harm to your house. They will not eat anything in your home. Best thing to do is to vacuum them up and then dispose of the vacuum bag. Do not try to squash them because they smell terrible and cause a mess.

Problem-free shrubs

Berberis x gladwynensis, or William Penn barberry. Itís a dense medium, evergreen shrub for full sun with thorns that deter deer. It has tiny yellow flowers in spring, and is relatively drought-tolerant. Cold hardy Zones 6-9.

Mahonia bealei, or leatherleaf mahonia. Like Mahonia aquifolium, it bears beautiful blue fruit, needs shade and produces lemon-yellow, fragrant flowers in early spring. Cold hardy Zones 5-8.

Prunus laurocerasus, or Otto Luykins cherry laurel. Itís a fast-growing evergreen with leathery, glossy dark-green leaves and blooms mid-spring with white flower spike. The plant grows in part shade to full sun. Cold hardy Zones 6-9.

Viburnum dentatum, or arrowwood viburnum. This multi-stemmed dense, large shrub adapts to a variety of soils and grows in sun or partial shade. It has no serious pests or diseases and is valued for its durability and white flowers. Cold hardy Zones 3-8.

Problem-free trees

Cornus kousa, or kousa dogwood. This small tree is native to China and Japan. Although it is no replacement for the native flowering dogwood, Cornus kousa dogwood resists Discula anthracnose, the fungal disease that has killed many native dogwoods along the East Coast. Cold hardy Zones 5-8.

Ginkgo biloba, or ginkgo. Itís a species that has survived since the age of the dinosaurs, so it is no surprise that it is very disease and insect resistant. Be sure to buy the male species so that you donít get the messy, smelly fruit. The ginkgo grows to a large size and has beautiful bright-yellow fall foliage color. Cold hardy Zones 3-8.

Styrax japonica, or Japanese snowbell. This dainty, low-branched small tree is amazingly trouble-free. It produces numerous pendulous, fragrant white flowers in May. Cold hardy Zones 5-8.

Zelkova serrata, or Japanese zelkova. Itís related to the elms but is resistant to Dutch elm disease, elm leaf beetle and Japanese beetle. It has a vase-shaped growth habit, somewhat similar to the American elm. It is wind and drought-tolerant, and performs well in urban landscapes. There is also a lovely variegated variety. Cold hardy Zones 5-8.



McClatchy-Tribune Information Services