Iris can be transplanted almost any time

Irises flower best when the bed is dug and the plants divided every few years. WALTER REEVES

Irises flower best when the bed is dug and the plants divided every few years. WALTER REEVES

Q: When can I transplant iris? How much sun should they have in their new home? Mackie Nisbett, email

A: You can move them almost any time. Early summer, after they finish blooming, is fine but I usually wait until fall because there is less demand then for water by the leaves. Iris grow best in full sun as long as you can water them occasionally in the heat of summer.

Q: Squirrels appear to be nesting in a knot hole in my ancient oak tree. Will they hurt it? Lou Tankersley, email

A: I can't think of any damage the squirrels might do. They don't usually gnaw oak bark nor do they enlarge a nesting area into living wood, which could damage the tree.

Q: I want to replace my front lawn. I have heard TifBlair centipede grass is better than the old centipede grass. Is this true? Donald Jarman, McDonough

A: TifBlair centipede grass is an excellent turfgrass, available in both sod and seed forms. It was bred and tested in both Tifton and Blairsville to make sure it could withstand cold damage as well as heat and drought stress. If you plant it, resist the temptation to fertilize often. Only one or two applications are needed each year. Make sure your mowing height is between 1 1/2" and 2" high. Differing from this can lead to weather damage. Weed killers and weed preventers can damage centipede grass as well. Read herbicide labels and follow them exactly.

Q: My elderly mother has decided that she really wants a crabapple tree that has green fruit when ripe, like she remembers from growing up. What do you suggest? Gene Baxley, email

A: Almost all crabapples bear fruit in some shade of red. None are solid green. Keep in mind that the most common definition of a crabapple is simply a tree that yields fruit less than 2" in diameter. Your mother may be remembering a poorly maintained green-fruited apple tree. If you can persuade her to accept a red-fruited tree, look for 'Dolgo'. It bears nicely sized fruit and is resistant to fire blight disease.

Q: In late April I saw ten birds attack my mahonia shrub. I watched bird after bird swallow those beautiful blue berries down their throats like a snake does his dinner. Are mahonia berries edible by humans? Pat Conklin, email

A: I'm not a doctor but several websites mention that mahonia berries are edible when fully ripe and soft. One source says the berries contain berberine, which might be harmful in some situations. Proceed with caution.

Q: I found a box of agricultural dolomitic lime in our dry basement dated 2009. It is still powdery, no clumps. Is it still useful for tomatoes? Rita Yeazel, email

A: Lime deteriorates slowly, even when it gets wet. Since your lime is dry and powdery, it is just as effective for soil application today as it was nine years ago.