Q: My old purple-leaf plum trees unexpectedly have lots of red skinned fruit on them. Since it’s fashionable to grow edibles in our landscape, how I can tell whether these plums are edible for humans (I don’t want to be the tester!).

A: The fruit is eminently edible; just don’t eat too many or you’ll have a big tummy ache. Other gardeners report more fruit on their purple-leaf plums this year than in the past. We know that stress triggers a strong flowering/fruiting response the year after it occurs. My guess is that drought caused the increase in fruit this year.