Q. My mother has two lilacs. They are growing and doing well but only one of them flowers every year. Why is that? -- Devra Mallner, Marietta

A. In order to bloom, some lilacs need more winter chill hours than others. This is why transplanted lilacs that bloomed wonderfully in Chicago or Boston sometimes refuse to flower in Georgia. Southern gardeners report that ‘Angel White’, ‘Dark Knight’, ‘Betsy Ross’ and ‘Miss Kim’ bloom reliably for them. Remember that lilacs prefer a soil pH that’s almost neutral. It’s not a bad idea to throw a handful of garden lime around each plant each year.

Q. My co-workers and I were wondering why a huge pile of wood chips makes steam after being dumped. -- Richard Whitley, email

A. The condensed water vapor (steam) is caused by the heat of billions of fungi and bacteria digesting fresh wood and sap. Digestion is just a slow form of oxidation or burning. If you and a billion co-workers were eating lunch in the same room, you'd heat up, too!

Q. My wife and I recently purchased seven acres in Union County. We've planted several hemlocks. How do I prevent wooly adelgid attack? -- Walter Cannon, Blairsville

A. Wooly adelgid, a sap-sucking insect, has killed thousands of hemlocks in North Georgia so I can understand why you’re worried. You are faced with yearly application of a systemic insecticide to each tree to prevent infestation. The recommended chemical is imidacloprid, found in several retail products. Your local expert on adelgid control is Union County extension agent Mickey Cummings. His office loans citizens a soil injector tool that can be used to put the chemical into the ground around your hemlock trees.

Q. Where can I buy ‘Meyer' zoysia grass seeds? I estimate that plowing my yard and seeding would be less expensive than buying sod. -- Jim Mckinney, Acworth

A. ‘Meyer' zoysia seed isn't available because it doesn't reproduce true to its parentage. Instead, look for ‘Zenith' zoysia, which is very similar to ‘Meyer'. Remember that zoysia is difficult to start from seed in conditions other than a "bare ground" beginning. In other words, you can't plant it among existing weeds or lawn grass and expect it to succeed. If you intend to start from bare ground, kill all plants in your lawn now with glyphosate (Roundup, etc.). Till the area and add organic matter and lime if needed. Rake smooth and plant seed in early May. Water daily for two weeks to keep the upper surface of the soil moist but don't let it become soggy. After the seedlings sprout you can start weaning the grass back to a single deep watering each week. Next year you won't need to water at all.

Listen to Walter Reeves Saturday mornings on AM 750 and now 95.5 FM News-Talk WSB. Visit his website, www.walterreeves.com, or join his Facebook fan page at xrl.us/wrfacebook for more garden tips.