UGA publications a great gardening resource

Q: This year I planted a bed of wild strawberries but mock strawberries have invaded! How can I tell them apart so I can pull the weed and keep the wonderful? — Susan Marks, Cartersville

A: The leaves of the two plants are very similar, so the best way is simply to wait for flowers. As you've no doubt observed, the flowers of mock strawberry, Potentilla indica, are yellow, and the flowers of edible strawberry, Fragaria species, are white.

Q: How do you keep variegated leaves variegated? I have a green spiderwort with white variegation. It looks very healthy, but the leaves are going all green. I have an acid-green heuchera, but it, too, is going darker. — Elaine Bolton, email

A: Variegation or other unforeseen changes in leaf color are most often caused by genetic mutation: A leaf bud gets damaged by a cosmic ray or a chemical aberration and it then produces cells that aren't the same color as the parent plant or branch. Some are stable traits that seem never to change back to their different-colored origin. Others are less stable and weakly (or strongly) revert to "looks like mama looks." I'm sure you've seen a variegated privet hedge with patches of dark green in the light green foliage.

In evolutionary terms, lighter variegation does a plant no favors, since lighter cells don’t photosynthesize as much as darker ones. My guess is that your plants are slowly reverting. The best way to deal with it is to clip out unwanted leaves at the base and give the plant enough TLC to make it produce new leaves from the variegated part of the crown.

Q: At my former home in Texas I had two papershell pecan trees and would like to plant one here. Do I need to have two different pollination types or do I need two trees of the same type? — Mike Fleming, Lake Lanier

A: "Papershell" is just a descriptive name given to improved varieties of pecan that have resistance to disease and insects and which bear reasonably-sized nuts. This is in contrast with some of the native seedling pecans, which can have nuts as hard as rocks. 'Stuart' was one of the first pecans described as papershell. When choosing a backyard pecan tree, choose one that has the most resistance to scab disease. Otherwise you might wait five years to get your first crop, only to find that the nuts abort before maturing, due to this devastating fungus. The latest breeding and selection efforts have produced 'Amling', 'Sumner', 'Elliott' and 'McMillan'. You will need two varieties for best pollination.You'll likely have to go online to find my recommended varieties. Before trusting an online nursery, check their reputation at the Garden Watchdog, bit.ly/GAwatchdog.