Question: What is the best way to kill English ivy? We have a large area and want to get rid of it.

Answer: If you want to control English ivy, you must be persistent. Plants can be removed by hand pulling. Frequent mowing close to ground level will eventually starve the plant, but this will take time. The waxy surface of English ivy is a barrier to the ready absorption of herbicides. Some gardeners tell me that they have had luck with an herbicide called Roundup Pro 4L and they apply it in early spring when three-five new leaves have fully expanded. Be aware that this herbicide is non-selective and will kill any non-target plants that the spray touches.

Q: Each year I set out calla lily (Zantedeschia aethiopica) rhizomes in late April. Gorgeous foliage appears but no blooms. What am I doing wrong?

A: Calla lilies should be grown in full sun or partial shade in fertile soil. You should amend the bed with copious amounts of organic matter, such as compost. Also try using a complete slow-release fertilizer, such as a 9-9-6, at the first sign of growth.

Calla lilies also require plenty of moisture. As soon as the leaves appear give your plants supplemental water. Apply a 2-inch layer of mulch to conserve moisture and suppress weeds.

Q: Moss is growing in my lawn and seems to be spreading. Is there anything I can do to get rid of it?

A: Moss thrives in lawns where there is poorly drained or wet soil, low fertility, acidic soil, soil compaction and excessive shade. A long-term solution is to improve the soil fertility and maintain an appropriate pH. Have your soil tested, then fertilize and lime accordingly. Shade is a difficult problem to correct. Select shade-tolerant turf-grass cultivars and mow at the highest recommended height to promote deep rooting.

If your mossy area receives fewer than four hours of sunlight a day, you may have to give up on grass and plant some ground covers such as pachysandra.

Contact Tim Morehouse by Web site: www.getmoregarden.com; mail: c/o Cincinnati Enquirer. (If writing, enclose a self-addressed, stamped envelope.)