Hydrangeas indoors and out

May 13, 2008

Those potted hydrangeas from the flower shop or supermarket are appealing this time of year with their big, floppy blooms in springtime hues of pink or blue (occasionally white). Understandably, many became thank-you gifts to moms on Sunday.

Potted hydrangeas – often called florist hydrangeas – are easy to care for indoors, providing you keep the soil moist. Don’t let them dry out! You’ll find that those large leaves and big blooms make them thirsty plants.

But don’t allow water to accumulate at the bottom of the pot. If the pot is wrapped in foil, poke a few holes in the bottom and put a saucer beneath. There’s no quicker way to kill any indoor plant than letting its roots stand in water.

You’ll be tempted to put the plant on a table in the middle of the room. And that’s fine at night, if you like. But during the day, a hydrangea is going to need more light.

Place the plant in good bright light – light that casts a shadow – with at least some direct sun. It’s fine to cut off the flowers after they fade, if you want. It isn’t necessary, though.

But don’t think that’s it. A potted hydrangea is a gift that keeps on giving. It can be planted outdoors after all chance of frost is past if you live in Zone 6 and south. (It’s worth trying in Zone 5, too. Just plant the hydrangea in a protected place.)

Outdoors, these old-fashioned charmers like to grow in partial sun. A spot with morning sun and afternoon shade is ideal. So is an area with moist soil or one that can be easily reached by a hose. Outdoors, as well as in, hydrangeas want plenty of water.

The main problem with these attractive shrubs is that they’re very sensitive to frost damage in spring. I’ve been known to keep an old quilt or discarded mattress pad by the back door so I could rush outside in the evening after the TV weather forecaster predicted frost and toss it over my hydrangeas so the flower buds wouldn’t freeze!

When a hydrangea doesn’t bloom in the spring, frost is often the culprit. So if it’s still chilly where you live, wait a little longer before moving your potted plant into the great outdoors.

But that’s no problem. Hydrangeas are just as pleasant indoors as they are outside.