By Brad Haire
University of Georgia

A University of Georgia scientist wants to see hydrangeas in
bloom sit proudly beside showy spring plants in garden centers
each year. So he’s giving them an early-winter wake-up call.

Hydrangeas have been faithful, shade-loving summer friends to
Georgia gardeners for a long time. But they often flower too
late to entice eager spring plant buyers, said Jim Midcap, a
horticulturist with the UGA Extension Service.

Nursery-grown hydrangeas generally don’t bloom until June.

“Most gardeners make their purchasing choices for the year in
March, April or early May,” Midcap said. “They miss seeing the
hydrangea in bloom.”

Wake up!

Midcap is working to see if nursery hydrangeas can be forced to
bloom earlier and meet that early-spring consumer demand for big
blooms and bright color. So far, the plants in his study seem
willing to come out of their winter dormancy earlier with the
right conditions.

Midcap began placing hydrangeas from outside plots into
greenhouses in mid-January last year. He continued every two
weeks until the end of February. The greenhouses gave the
hydrangeas the heat and protection they wanted to break their
winter dormancy.

He was looking for the best time to bring the hydrangeas in to
force them to produce blooms by April 15. This date is
considered the last day of possible frost for much of Georgia.
And it falls in the middle of that spring plant-buying frenzy.

Nursery growers in Georgia could use the method to reach the
earlier spring market and get premium prices for hydrangeas,
Midcap said.

“And consumers will be able to see how the hydrangeas bloom and
be able to put them in the garden at the best time: spring,” he
said.

Midcap repeated the study this year. He has about 1200
hydrangeas waking up in greenhouses now. They should have plenty
of flowers around April 15.

Home gardeners with greenhouses could do the same with
hydrangeas in their yards. Hydrangeas already in pots may do
better than those you’ll have to dig up and place in pots to
bring into the greenhouse, he said.

Reflower

Midcap used reflowering hydrangea cultivars for his study.
Reflowering hydrangeas grow flower buds on new wood and are
relatively new to the market. You should find them in most
garden centers this year. Look for hydrangeas named Endless
Summer and Penny Mac.

And if you haven’t already, don’t prune the hydrangeas in your
garden now, he said, unless they’re one of the reflowering
varieties. You’ll cut your flower buds off. If you do, you won’t
have as many flowers this summer.

Hydrangeas should be pruned in the summer soon after the year’s
flowering has stopped.