One of the pleasures of writing the “Gardening Corner” every week is that many topics are offered to me in the form of questions or as in the case of this week’s subject, public service announcements. When I receive queries or suggestions from you, I remain aware of the topics of interest to home gardeners and property owners on the Middle Peninsula.

I received an email from Gloucester resident Dr. David Justis concerning Euphorbia helioscopia, an herbaceous annual weed commonly called sun spurge, wart spurge (a hint to one of the plant’s uses in folk medicine), or madwoman’s milk, which should tell you that this is a plant you want to leave alone.

You may remember that in 2019 I wrote about another species of Euphorbia (E. x martinii “Blackbird”), an evergreen perennial. It so happens that more than 7,000 species of Euphorbia exist worldwide, ranging from tender annuals, biennials, and perennials to hardy evergreens. About percent of Euphorbia species are succulents. To make id...