NEIL SPERRYGardener's Mailbag

Dear Neil: I would like o keep my vitex plant at approximately 6 1/2 feet tall. Can I prune it to accomplish that task?

A: I’m assuming it’s a standard vitex. If so, it will develop a trunk that could be up to 8 or 10 inches in diameter. That will be really awkward looking on a tiny 6-1/2 foot shrub. You can certainly prune it heavily each spring right after it blooms and then again in fall after the second round of flowers, but you might be more satisfied with a dwarf form like Blue Diddley.

SOIL IS KEY

Dear Neil: Why won’t my Encore azaleas put on more leaves? They have bloomed fairly well, but the leaves are so sparse. I feed them with azalea food three times a year.

A: Success with all azaleas revolves around their planting soil. They thrive in acidic, sandy soils. When we grow them in tight clays, especially alkaline soils, they struggle after a few years. New growth is minimal, and blooms are reduced to a minimum. It looks like your bed probably needs to be reworked. You could try digging the plants out, adding 10 or 12 inches of fresh organic matter (sphagnum peat moss and pine bark mulch in equal amounts) and replanting the plants after you trim them back by half. Or you could do the bed preparation over again and buy fresh plants to set out for a more uniform and vigorous start. If they’re in an acidic soil already, you might try trimming them back rather heavily, then applying an all-nitrogen fertilizer to promote vigorous regrowth.

SHADE OFTEN CULPRIT

Dear Neil: My yard got a fungus four years ago. I had a beautiful green lawn, but now I have only dirt and weeds. I don’t know where to start. I’m a 60-year-old grandmother living alone. I can still mow, but right now there’s almost nothing to mow. Help!

A: Unfortunately that’s not a lot of information to get me started. Funguses very rarely kill entire yards. It would help to know what kind of grass was involved and whether drought or cold might have come into play. Without any concrete information what I can offer is that 95 percent of the time when I actually see lawns after hearing a description like this, the grass has died out due to insufficient sunlight. Usually it’s because trees have grown larger over the years until things finally have gotten so shady that the grass (usually St. Augustine) just can’t hold its own. It dies away almost as if a disease were involved, but in reality, it’s all about the light. The only solution in those cases, assuming homeowners don’t want to remove trees, is to plant a shade-tolerant groundcover. I have no idea whether that’s of any value in your situation, but perhaps it’s a start.

AZALEAS ARE HARDY

Dear Neil: Our son lives in a part of Texas where temperatures dropped into the 20s a couple of weeks ago. Crape myrtles’ new growth was burned pretty badly. Will they come back?

A: Absolutely. In fact, they probably already have started putting out new leaves by the time this makes it to press. Crape myrtles are durable.

Have a question you’d like Neil to consider? Mail it to him in care of this newspaper or email him at mailbag@sperrygardens.com. Neil regrets that he cannot reply to questions individually.