Question: : My irises haven't bloomed for three years. Leaves come up, but no flowers.
Answer: : Your irises may be planted too deeply. This is a classic reason why they fail to bloom, even when foliage is present. The top of the rhizome should be showing at the soil's surface.
Irises also require at least six hours of sun a day to bloom, and cannot be allowed to dry out, especially in the critical spring months when buds are set. At the same time, if they are over-watered then you may get some rot, so watering should be done carefully. A very late freeze can cause flower stalks to abort. Overcrowding will stop flowering, too.
Question: : Moss is killing my grass. I raked it out. How do I keep it from returning?
Answer: : Moss doesn't kill grass. It takes advantage of poor lawn-growing conditions. The five conditions that favor moss and weaken grass are: heavy shade, acid soil, compacted soil, soggy soil and low fertility. If you can't change the conditions, such as adding lime to make the soil less acid or removing tree branches to let in more sunlight, then switch strategies.
Moss itself makes a lovely ground cover. Create beds of shade-loving plants in shade, water-loving plants in a wet spot. Call us for more options.
Question: : Mosquitoes attack every time we use our yard. We don't have a birdbath or pond. Where else could they be?
Answer: : Daytime biting indicates Asian tiger mosquitoes. In just over a week, they can breed in as little as a tablespoon of standing water. Some surprising places to look are: umbrella stands, flower pot saucers, depressions in plastic tarps, poorly draining rain gutters, toys, upside down furniture and tires.
Nibali, a horticulture consultant, works at Maryland Cooperative Extension's Home and Garden Information Center, and Traunfeld is the director of the Home and Garden Information Center. The center offers free gardening information. Call 800-342-2507 or e-mail plant and pest questions at the Web site hgic.umd.edu
