Q: Winter really hurt my St. Augustine. It looks like half of it won't be coming back, even though the rest of it is green and growing fairly well. What can I do to help it? The same problem showed up last year.

A: Unless you're talking about a really shady area, it's probably Take All Root Rot, a fungal disease that has attacked Texas St. Augustine the past several years. Affected grass is dead and lifeless on top of the soil, almost like grub worm damage (but grubs are not present). Fungicides do not work very well, but research done by plant pathologist Dr. Phil Colbaugh, retired from Texas A&amp;M, shows that a 1-inch layer of sphagnum peat moss will create an acidic layer on top of the ground and will significantly suppress the organism. That allows the grass to re-establish and cover.

Normally, the peat is broken up and raked out in late April or early May, but you could still treat. You can find more information about the disease and photos at www.neil sperry.com. Click on Most-Asked Questions, then on "lawns" and you'll see it.


Q: Why would a potted lemon tree be sparsely leafed and only bear a couple of lemons each year? I see others' trees, and they're thriving and full.

A: It could be root-bound, or its potting soil may have become depleted (assuming it was good in the first place). It might need more light, or it might need nitrogen. Perhaps it got too dry at some point and has struggled to recover ever since. Just a few thoughts.


Q: How good a plant is pineapple guava? How well is it adapted to Texas? The garden center manager at the national chain didn't know what it was, and it didn't have a label. It was marked down. I found out later what I had.

A: Pineapple guava (Feijoa sellowiana) is a handsome shrub that grows well in the southern half of Texas. It's winter-hardy to Zone 8, meaning that temperatures into the low teens could injure or kill it. Give it morning sun, with some protection from the hot afternoon sun. Keep it moist for best performance.


Q: What can I do for a mature catalpa tree that has died back significantly and that now has a bunch of sprouts coming up around its base?

A: It sounds like there's been some type of trunk damage, perhaps at the point at which the new growth is sprouting. The decision of whether to save the tree is going to have to rest on your shoulders. It will be odd-looking at best. If it were my situation, I'd remove it and replace it with a more durable species. Your retail nurseryman can explain the several fine options.

