Expert Advice: Trees & Shrubs

Q. Can you give me any advice on planting dogwood trees? My wife and I just bought two dogwoods -- one pink and one white. We live in Chester Springs, about 30 minutes west of Philadelphia. The soil is left over from an old tree farm that was once were our property is. How much sun do dogwood trees need? How about soil tips? Should I use moss?

A. Flowering dogwoods prefer partial shade in a location that's protected from drying winds. They like a rich, organic soil and won't do well in straight clay or sand. I'm not sure what you mean by moss, but I'll assume you mean mixing peat moss with the soil. That would be fine at planting time, but don't overdo it. Also, be sure to mulch your trees to maintain soil moisture.

Q. I planted a mountain ash tree three years ago and this spring it is not showing any sign of leaves. The other ash trees in my neighborhood have leaves. I tried a scratch test in several areas of the tree and they're all green and there is a shoot at the bottom of it that has leaves. I live in Pennsylvania, Zone 5, and the tree has done well in the past.

A. Mountain ash trees can have a number of severe problems (they are a short-lived tree as well). I can't diagnose this tree without more information, but it could have been hurt by a dry fall and cold winter. Or it could have succumbed to a number of other diseases. It's really hard to tell with little information. My guess, however, is that the winter was at fault. If it comes from the base, but the top does not sprout, you'll have to cut it down.