QUESTION: I have a moist, partly shaded planting bed that needs a little zip. My sister suggested coral bells (Heuchera sanguinea), which got us both wondering about the song. How can coral bells be two different plants at the same time?

ANSWER: Many gardeners recall the old children's song that starts: "White coral bells upon a slender stalk/Lilies of the valley deck my garden walk." And no doubt many have noticed the seeming contradiction. Lilies of the valley (Convallaria majalus) have white bell-like flowers and narrow, upright bright green leaves. Coral bells are bushy broad-leafed plants, and their flowers are typically red.

Both plants can be called coral bells because coral can be milky white as well as its namesake orange-red, and in the days when coral jewelry was common, everybody knew it.

As far as zip is concerned, why not intersperse lilies of the valley with an assortment of heucheras? Both should thrive in moist semi-shade, in neutral to slightly acid soil. They would give you bells galore as well as a tapestry of handsomely contrasting leaves.

These days all heucheras can be called coral bells, and they are all great foliage plants, with leaves that may be solid or mottled, scalloped or ruffled, dark green, bronze, orange or maroon. Many have a metallic overlay, and some have such strong graphic appeal that they shine more brightly than the flowers. The leaves of Silver Scrolls, for instance, are pewter with near-black veins, a living Art Deco delight.

Silver Scrolls is a white-flowered variety, and coral bells also come in pinks. But only the jewelry store has black. Large selections of heucheras are sold by Busse Gardens, 8000-544-3192 or www.bussegardens.com; and by Lee's Gardens, 309-925-5262 or www.leesgardens.com.

QUESTION: The 30-year-old linden tree in our yard has many surface roots that make it difficult to mow the grass. Can I cut and remove the roots without damaging the tree?ANSWER: Lindens get a lot of good press for their disinclination to make surface roots, so it's tempting to think of your trees' mower-foilers as extras that it would not miss. But trees do not make roots for the fun of it.You may have very dense, hard subsoil that roots cannot penetrate. Or years of watering the lawn and not watering the tree may have led the roots upward. Whatever the cause, the tree is dependent on them now. It would probably be safe to remove a few of the most bothersome, not more than 10 percent of the total. Any more than that and you might as well remove the tree.

QUESTION: I bought some bagged lily bulbs (packed in wood shavings) that turned out to have already grown long pale stems. Do I leave the stems above ground or bury them?ANSWER: Bury them, with the tops barely breaking the surface. The stems are probably growing sideways instead of straight up, but don't worry about that. Just try to get the bulbs as deep as possible.And don't expect too much from them this first year; they have already exhausted themselves trying to grow while out of the ground. There is a good chance that they will recover, but it may be two or three years before you get anything like the picture on the package.Address questions to Garden Q&A, The New York Times, 229 W. 43rd St., New York 10036, or e-mail gardening@nytimes.com. Those of general interest will be published. Unpublished questions cannot be answered individually.By N.Y. Times Service