Plantings to Brighten Your Winter and Your Shade

Time again to answer some of your questions about fall gardening.

Q: I live in a 20-foot-wide D.C. rowhouse and would like to plant one or two shrubs in front of my porch that will remain fairly small, require little maintenance and not overtake the flower bed. The area gets full sun. I want to have winter interest and attract birds. It would be even better if it were a native species. Do such shrubs exist? -- Lisa

A: Shrubs can offer fragrance, fall color and a network of branches that give architectural value to the garden year-round. Birds will flit through them in winter and nest in spring. Little Henry Virginia sweetspire ( Itea virginica"Little Henry") is a native plant with fragrant early summer flowers and beautiful maroon leaf color in fall. It grows three to four feet high. Little Henry is not a rampant grower, but some maintenance is needed every couple of years to keep it small. Smooth witherod ( Viburnum nudum) is an extremely fragrant native with white flowers; it has striking reddish-purple fall color. It grows about six feet tall in 10 years without pruning. Both shrubs are deciduous.

What suggestions do you have for providing color in shady areas?

-- Ed

Color in shade can be accomplished with foliage and flowers. Here are a few suggestions: Jack Frost false forget-me-not ( Brunnera macrophylla"Jack Frost"), Japanese painted fern ( Athyrium niponicum"Pictum"), summersweet ( Clethra alnifolia), witch hazel ( Hamamelis), winter hazel ( Corylopsis), golden hakone grass ( Hakonechloa macra aureola), Carol Mackie Daphne ( Daphne X burkwoodii"Carol Mackie") and black mondo grass ( Ophiopogon planiscapus).

Why didn't my marigold buds open completely? They are in planters.

-- Veronica

Those flower buds might be drought-stressed. Pick them off. If the marigold has healthy foliage, it will form new flowers and do well for the rest of the season. In containers, keep the marigolds moist, well drained and fertilized every other watering with a water-soluble fertilizer such as Miracle-Gro. They grow best in full sun. Dead flowers might also be caused by a fungus or mold, but this would affect the leaves, too. If this is the case, remove the plants and install some chrysanthemums for fall color, or pansies for fall and spring color. If disease was the problem, replace the soil in the containers before planting again.

Twelve nubs, eighteen feet by six feet, were installed as traffic-calming measures about 15 years ago in my neighborhood. They were planted with blue rug junipers and Stella d'Oro day lilies. Most of the nubs look fine, but three are weed patches. Would you recommend replanting these nubs with the same plants, or are there other plants you think would look good in these conditions?

-- Susan

Maintenance for island traffic calmers is virtually nonexistent. They would be better paved in brick or ornamental stone. The thought recently occurred to me while sitting at a traffic light on Connecticut Avenue in Chevy Chase. The median was a collection of weeds, probably because of the drought. When it was installed, five or six years ago, the concept was sound and the plants looked good. The plants are drought-tolerant fountain grass ( Pennisetum alopecuroides) and creeping lily-turf ( Liriope spicata).

Few gardens become completely self-sustaining, especially in the middle of the street. That most of your islands look good is a testament to the planning that was done 15 years ago and subsequent maintenance. Apparently, there were ample organic material and moisture to get the site started, both plants are drought-tolerant, and the width of the space was sufficient. For the lowest maintenance, use the same plants. Water while they are establishing. Install native wildflowers or another mix of native plants if you have someone managing the site who knows what to pull and what to leave. With blue rug junipers ( Juniperus horizontalis"Blue Rug") and Stella d'Oro day lilies ( Hemerocallis"Stella de Oro"), there should be no question about what to leave.

When is the best time of year to prune cherry laurels? I am a novice gardener. -- Ellen

Cherry laurels are best pruned after flowering. If you are renewing them drastically, reduce the height gradually. Remove one-third of the largest stems. Take them back to the base or to a lower stem. Over three years, you will have reduced the plant size significantly. If this is not enough, you can shear the plant to reduce the height by one-third. This will also make it much fuller.

A couple of years ago, we removed the hemlocks between my yard and my neighbor's. We want to plant a screen that will not be nibbled by deer. Would cryptomeria screen the neighbor without being too large for the space? Do you recommend a particular cultivar? I'd also like to create an evergreen screen in a shady area. Would you give me some suggestions? -- Joanne

Yoshino cryptomeria ( C. japonica"Yoshino") has proven to be a dependable evergreen screen in partial sun to partial shade; it is not known to be eaten by deer. It will grow 30 to 40 feet tall by 10 to 15 feet wide in maturity. It is a good choice for partial shade -- five to six hours of sun. Another is viburnum, even though deer have started munching on several cultivars. If you choose them for partial shade, try leatherleaf or Allegheny viburnum ( V. rhytidophyllum or V. x rhytidophylloides"Allegheny").

Narrow evergreens that will do well if given enough sunlight -- six to eight hours -- include dragon lady holly ( Ilex aquipernyi), a narrow evergreen that grows four to six feet wide with spiny foliage that deters deer, and a trademarked red holly with spiny leaves that will possibly deter deer, called Festive. They do well with filtered sun. Festive grows into a 12-by-8-foot pyramidal tree. Another shrub to try is Graham Blandy boxwood ( Buxus sempervirens"Graham Blandy," a columnar evergreen that deer haven't started eating. It grows eight to nine feet tall and stays 18 to 20 inches wide in maturity.

We have a weeping willow that looks like it is drying out in parts. We have noticed that ants are crawling up the tree. Is there anything to do to save it from dying and prevent the ants from killing it? -- Mario and Celina

Weeping willows have many insect and disease problems. The dry areas might be because the tree needs moisture. We are nearly eight inches below our average annual rainfall to date. Soak the tree roots with water several times this month. The ants are not killing your tree; they are there because of honeydew excreted from insects called giant bark aphids. The aphids suck the sugars inside the bark and secrete the excess, making the branches sticky. Ants follow them to feed on the sugars.

You will often see black sooty mold on the bark, and later in the season, you can see masses of eggs coating the tree, sometimes with large infestations. If it is a large tree, have an arborist evaluate it. Otherwise, insecticidal soap is a good first defense against the aphids and ants. Follow the directions on the soap. If you see a serious infestation, you will need to monitor the tree next year and spray earlier to control the generations of giant bark aphids.

When would be the best time to trim back rose of Sharon? -- Tahma

Rose of Sharon ( Hibiscus syriacus) will flower until first frost, so the shrub should be cut back late in February, before growth begins in spring. Prune heavily. It flowers on current year's growth. Because it's constantly going to seed, it can become invasive. Keep it to a size at which it's easily deadheaded as flowers fade.

Joel M. Lerner is president of Environmental Design in Capitol View Park, Md. E-mail or contact him through his Web site, http://www.gardenlerner.com.