When you’re out-of-town, there are plenty of kennels and other facilities that will mind your dog or cat. In fact, the pet-care business is booming! However, the same options aren’t available for your houseplants. So what do you do?

First, keep in mind that plants can go for several days or even a couple of weeks without water. This frequently happens in their natural habitats. So if you’re gone for just a few days, your flora will probably be fine.

Flowering plants tend to...