Ask the gardeners

Q Could you mention some shrubs with aromatic blooms that we could plant around our outdoor living area? I have fond memories of such a fragrant planting around the backyard of my childhood home. We will include those that are hardy in a large part of the United States, including your state (Iowa). Folks should consult local nurserymen for varieties or species that are most suited to their areas.

Two spring favorites are crab apple and lilac. There are many fragrant azaleas, but remember two precautions: Be sure to provide an acid soil and see that your choices are hardy. We hesitate to recommend mock orange (Philadelphus) because of complaints that newer strains lack fragrance.

Roses, including old-fashioned species, should give fragrance and beauty through June and July and again in early fall. A dainty May-June bloomer is Daphne cneorum, a superb low-growing evergreen shrub with masses of tiny pink flowers. Carolina Allspice (Calycanthus floridus), also called strawberry shrub or sweet shrub, is a spring bloomer with an unforgettable, heady fragrance. No list is complete without Viburnum carlesii or one of its progeny. Often called fragrant snowball, it is an unrivaled spring bloomer. Because there are few fragrant shrubs for midsummer and fall bloom (for your area), we'll mention two vines that are easily trellised. Sweet Autumn clematis blooms from late summer into fall; Lonicera (honeysuckle) starts blooming in midsummer and continues into autumn. Q In December 1983 we saw beautiful potted ornamental peppers in a florist shop, for holiday gifts. In October 1984 we bought some seeds thinking we could grow our own gift plants in our small greenhouse. We were surprised to find they take much longer. They were in their best red color around Easter instead! When would you suggest we plant seeds to have them ready in December 1985?

Ornamental peppers need about six months to put on a show, hence should be sown the first week in June to be ready for December holidays. Sow seed boxes, cover lightly with the Peat-lite medium, maintain at 70 degrees F. or above, keep moist at all times, and they will be ready to transplant to 21/2-inch pots by the end of June.

In late July, transplant to 6-inch pots and pinch out tips to make them bushy. Your greenhouse may be too hot during the summer, so grow them outdoors until late summer or fall. Give them a liquid feeding about every two weeks. You can choose from varieties with cone-shaped, round, or pencil-thin fruits -- and they are edible if you can stand the heat. But do not mix any Christmas cherry with them; this creates Solanum Pseudo-capsicum, which is toxic. Peppers are true Capsicum. Q Could you recommend a colorful, low-growing (6 to 8 inches) annual that can be sown directly outdoors in May, which will bloom all summer? We want to have something striking around the edge of our new patio.

Thumbelina zinnias are the best we can think of. They sprout fast in warm soil, grow to blooming size very quickly, and continue all summer with an abundance of colorful 2-inch flowers. Q Do you have any suggestions for keeping tiny white grubs out of radish roots, without using toxic chemical pesticides?

You are referring to cabbage maggot, which also attacks radishes and other members of the crucifer family. They are the larvae of a one-fourth-inch-long, dark gray fly which lays eggs near the base of the stem. These hatch and larvae crawl down to the roots. Covering seedlings of radishes and transplants of other crucifers with the Reemay polyester material mentioned in Peter Tonge's column March 19 would help eliminate the first infestation and thus prevent a second brood of adults from emerging.

We've had success with two simple remedies passed along to us by master gardeners of yesteryear. One told us to sprinkle wood ashes on the row when planting seeds or transplants; the other said he always soaked his radish seeds in a little kerosene for half an hour and planted them while still wet. Q We sowed tomato seeds indoors on March 1, and seedlings looked very robust, but a few days later most of them flopped right over just as though something had pinched each stem at the soil line.

Your seedlings had what is known as ``damping off,'' a fungus. It is aggravated by lack of air circulation around the seedlings and by using a seed-starting medium which is not relatively ``sterile.'' Peat-lite mixes especially for starting seeds are made up of sterile ingredients such as sphagnum peat moss, vermiculite, and perlite. These are found in garden stores and are simpler to use than trying to mix your own, since they have the proper grade (size) particles. They do contain small amounts of fertilizer and there are some on the market that meet the standards for strict organic gardeners.

You can offset the stagnant air problem by placing a small fan about 10 feet away and having it blow, NOT on the seedlings, but across the area in front of the seedlings. Q A friend who recently left on a trip gave me a box of flower seeds she had acquired in the fall. Most were in their original packets, but among them was a plain envelope with ``Cape primrose-Wiesmoor hybrids'' on it. I am not familiar with this plant. Please tell me what kind of flowers to expect, how long it will take for them to bloom after I sow the seeds, plus any other pointers I would need to know.

You have some streptocarpus seeds, also called Cape primrose because they are indigenous to the Cape of Good Hope in South Africa. They are gesneriads as are gloxinias and African violets. The trumpet-shaped blooms of Weismoor hybrids may reach 4 or 5 inches, coming in shades of purple, white, red, and pink. Leaves may be 20 inches long, lying fairly flat with flowers 3 or 4 inches above them. Plants require six months from seed to blooms. Seeds should not be covered, as they germinate better when exposed to light. Keep moist and at 70 degrees F. Q Moles have ruined my lawn with numerous tunnels and have nibbled on my spring bulbs. How can I get rid of them and what shall I do to restore my lawn?

If the animal is eating bulbs and other vegetation, you have voles (which resemble tiny beavers) or other small rodents using the moles' runways. Moles are not rodents and their diets are almost exclusively insects, grubs, and earthworms. They are actually beneficial because they rid your lawn of harmful pests (as do skunks). Some folks use fiberglass, hot pepper sauce, and mothballs in runways. The moles have already moved, so these remedies would be for the voles. Castor beans (very toxic) can also be used. Harpoon traps are available at garden stores. As for our mole population, we merely thank them for ridding our lawn of grubs, tamp the dug up areas back in place, and sow some grass seed on the bare spots. To the garden editor:

After reading the suggestions you gave in one of your Q&A columns about starting and growing these fruitful plants in hanging baskets over the winter months, we decided to sow some in April of last year. We adhered to your growing instructions and had enough plants to give to friends, and still planted four large hanging baskets with three plants each. Ours started bearing in August and have continued all through the winter. We still have them on our sunporch that is no cooler than 50 degrees F. at night and between 70 and 80 degrees F. during the day. We keep soil moist at all times. They are still bearing. There hasn't been a week that we haven't had at least a few berries.

If you have a question about your garden, send it to the Garden Page, The Christian Science Monitor, One Norway Street, Boston, Mass. 02115.