Why do Japanese beetles attack some crape myrtles and not others?

Q: Every year, Japanese beetles attack my crape myrtle, but other crape myrtles in the neighborhood don’t seem to be affected. Why? Connie Stevens, Barrow County

A: Mechanical factors of the crape myrtle leaves could be part of the answer. By that, I mean that thick or hard-to-chew leaves would be less palatable to a Japanese beetle than thin, lush leaves. If you prune your crape myrtles in winter, the summer leaves will be thinner than on an unpruned plant. Different varieties might have slightly different leaf thickness too.

Q: My 12-year-old dwarf mondo grass is reverting to a longer form. Is this a thing? What do I do with it? Try to pull out the rogue clumps? Christi Ware, email

A: It could easily be a thing. Many dwarf plants are sports that were collected growing from a bigger plant. If these notably smaller plants can be propagated easily, they can be sold in a nursery. Then a homeowner who wants to grow something in the joints of a brick patio grabs some for their landscape. But hiding in the genes of the dwarf plant are the genes of its parents. Sometimes the dwarf plant sports a larger version of itself: the parent plant. It sounds like that’s what’s happening to you. Pulling out clumps of the taller plant is one option, but it would be a lot of work. Could you mow everything to a uniform height once or twice a year?

Q: I live in a huge forest so controlling fall leaves is hard. Am I wrong to shred them with a mower and spread them around the property, some close to the house? Dianne Wisner, Atlanta

A: They should be at least a foot away from the house foundation to prevent termite access. Otherwise, mulch away!

Q: I have had a new lawn since June and want to save it from moles. Will the cold drive them deeper underground? Would early spring be a better time to tackle this problem? Jane McLean, email

A: Moles are frustrating to control. There are no effective repellents. Chewing gum, mothballs and battery-powered vibrators are equally useless. Poisoning grubs only makes moles dig more vigorously as they search for earthworms. It is difficult to be successful with trapping and poisons without a lot of experience. I think my longtime suggestion to simply walk on the raised tunnels to crush them is easiest for homeowners to accomplish. If you walk the tunnels regularly and firmly, moles will seek other places to live.

Email Walter at georgiagardener@yahoo.com. Listen to his occasional garden comments on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, www.walterreeves.com, for the latest garden tips.