Too much water causes stem rot in impatiens
Q: I've had an ongoing problem over the years with impatiens. The stems seem to be rotted or severed at soil level. At first I used to think this was caused by snails but am now leaning toward some kind of stem rot. Can you confirm and suggest a cure? Thanks. Eric Mabin
A: You diagnosed the problem correctly. It is a stem rot called damping off and is common on herbaceous (nonwoody) plants such as impatiens. Too much water introduces and perpetuates the problem. Ease off on the water and remove infected plants, roots and soil. Follow up with a drench of the fungicides Monterey Aliette or Subdue, following label directions.
Figuring out soil and sod needs
Q: I have two large oak trees in my front yard. There are now roots above ground. At one time the grass was very difficult to grow because of shade from the trees. I would like to replace the dirt at some point and level it out so I can later lay down new sod. How do I measure square yards to know what amount I would need? I know of two choices to purchase dirt, by the truckload or by bags, and I know the sod will have to be laid over that right away. I can't afford landscaper fees. Genevieve Premru
A: Ideally, if the shade from the oaks is such that the turf won't grow, you would be better off using ground covers that will accept the lower light levels. Plant possibilities would include bromeliads; English ivy, Hedera helix; Algerian ivy, Hedera canariensis; Boston fern, Nephrolepis exaltata 'Bostoniensis'; pothos, Epipremnum aureum; cast iron plant, Aspidistra elatior; or spider plant, Chlorophytum capense.
If you want to stick with the sod idea, a poor second choice, there are several things to consider as you make your plans. To not damage the oaks, apply new soil only to the top of the roots. St. Augustine grass is your most shade-tolerant turf, but it must be sprinkled, so an irrigation system will be necessary. To figure the amount of turf, consider that there is 400 square feet of sand-grown sod per pallet or 500 square feet of muck-grown sod per pallet. Muck-grown sod should be rolled after installation. A pallet of sod weighs 3,000 pounds, and usually is delivered with a two-pallet minimum, so consider whether you're up to this task as well. Weigh your alternatives; maybe a professional landscaper isn't such a bad idea. If so, make sure he or she is certified by the Florida Nursery, Growers and Landscape Association (fngla.com).