Q: Last year we planted several petunias that we bought from a nursery. In full sun, they gave us fantastic blooms while spreading like crazy. This spring many are green and seem to be putting on new growth. Will they bloom again this year?
A: The old time petunia, Petunia grandiflora, is an annual. However, most nursery petunias are hybrids that have some perennial Petunia integrifolia in their parentage. (For fun, try repeating that sentence out loud a couple of times.)
The popular “Wave” petunias and now the “Tidal Wave” varieties are good examples. The perennial petunias are native to South America and can tolerate temperatures in the 20′s. Since your plants didn’t die this winter, they will likely perform as well this year as they did last summer.