Gardening advice for hostas, day lillies, and sloped lawns

Q: My husband and I planted some hostas in the front of the house this spring. They get morning sun. The summer's heat and humidity have made many of the leaves turn brown. I water them every other day. Is there anything I can do to revitalize the plants? --St. Louis, Missouri

A: Unfortunately, hostas put out only one set of leaves a year -- so you're stuck with the foliage until next year. However, to keep this from being a repeat performance, I'd amend topdress the soil with a couple of inches of compost this fall. The compost will decompose over the winter, helping your hostas thrive. Also, I'd be sure and use mulch over the top of the soil next season. Mulch helps keep the soil moist and cool. Any kind of organic mulch -- such as compost, pine needles, or shredded bark -- will do. If possible, also give them a little more shade. If you can't move them, then planting something a little taller nearby might help give them the extra shade they want.

Q: My daylilies are growing like crazy this year. I think I need to divide them. When's the best time? --Bloomsfield, Iowa

A: Daylilies are tough, adaptable plants, so you can divide them anytime from spring to fall. It's easiest on the plants, though, if you do it in the cooler months. If you divide them in spring, be sure they get plenty of water so they become established before summer's heat arrives. If you divide them in fall, be sure they have at least a month to become established before the soil freezes. Good luck!

Q: I planted a "Forest Pansy" redbud this spring. It had beautiful burgundy leaves. Now the leaves have turned green. What happened? How do I get the burgundy leaves back? --Memphis, Tennessee

A: Many burgundy-leaf plants show their gorgeous leaf color in spring, but as the summer heats up, the color fades back to green. This is a characteristic of the plant, and there's nothing you can really do to keep it from happening. To prolong the purple tones longer in the season, it helps to keep the soil moist (apply a 2-inch-deep layer of mulch over the soil) and the redbud shaded from the afternoon sun.

Q: My backyard is on a slope. I cleared the yard, built steps into the grade, and now would like to put sod down. The yard is heavily shaded by old-growth hardwoods and receives about two to three hours of semidirect sunlight each day. Do you think sod will grow in these conditions? --Charlotte, North Carolina

A: The level of shade you describe sounds pretty substantial. My guess is that any grass, regardless of variety, is going to struggle in light that low. You might consider using shade-loving perennials instead. Slopes can easily be covered with hostas, pachysandra, vinca, or wild ginger that do much better in shade than grass. Many bloom attractively and are lower maintenance than turf (since they don't need mowing).

Q: My tomato plants have done well so far this season and even have green tomatoes now. Last week, however, the lower leaves became yellow, and the tomatoes don't seem to be ripening. What's happening? --Burlington, Vermont

A: Tomatoes are susceptible to a large number of diseases. It sounds like your plants may be infected with one. Unfortunately, many of these diseases start their attacks on the plant in the lower leaves.

At this point, there's not a whole lot you can do but remove the infected leaves. If you catch the diseases early enough, you can often keep them limited to the leaves. By removing the leaves, you keep any diseases from spreading throughout the plant.

Questions for the garden expert?

Justin W. Hancock is a gardening editor at Better Homes and Gardens Special Interest Publications®. Visit http://bhg.com/app/qa/plant to see our most commonly received questions or to e-mail your own inquiry to our team of gardening experts.