In the Garden:
Mid-Atlantic
May, 2007
Regional Report

Share |
2453

Nursery owner Jim Gears shows where he pruned off dead branches damaged in February's abrupt cold spell.

Green Wisdom Afoot at Plant Sales

My Sunday afternoon mission was to find hefty rhodies and native, shade- and drought-tolerant perennials -- Heuchera americana, Phlox stolonifera, autumn fern at the Jenkins Arboretum plant sale in Devon, Pennsylvania.

The benches were stocked with dozens of deciduous azaleas blooming or ready to pop, airy lavender-flowered columbine, iris, eupatorium. While the plants caught my eye, the lively conversations perked up my ears. Many of the volunteers answering questions were true plant afficionados (not sales people) eager to share their expertise.

Standing near several uncommon camellias, I thought of the brown-leaved 'Winter's Fancy' camellias that looked so vibrant when planted last spring. And the hollies lush and green into February, now crispy gray since March. So I gathered my courage and asked one volunteer three questions on many gardeners' minds this spring. What the heck happened to the leaves on the broad-leaved evergreens? Why so much dieback (dead branch tips and leaves)? And will the damaged shrubs live?

Frank Brouse of Brouse Wholesale Nursery in Norristown, Pennsylvania, shook his head. Winter was hard on his nursery rhododendrons. "I had more winter damage this year than ever before. It was such warm fall weather into January, it never got real cold. When it did get cold, the days were bright, sunny, windy. I think the rhodies started to think it was spring."

Plant growth depends on warmth, day length, and a combination of other things, Brouse explained. Last winter's warm winter gave plants unusual signals, which meant they didn't go dormant. Many plants didn't harden off properly; that is, they didn't go through the normal chemical changes to prepare for cold winter weather. When the February cold spell suddenly kicked in, plants weren't acclimated for the deep freeze.

Jim Gears of Octoraro Farm Nursery in West Chester concurred, adding that the sun desiccated (dried up) the broad, green leaves in western exposure. Rather than prompted by the cold to go dormant, the warm plants began to vernalize (grow as if it were spring). They started to leaf out before the February freeze, Gears observed. He noticed premature growth in some wildflowers, specifically Shooting Star that sprouted earlier than normal. Gears also suggested genetics played a role via parent species for hard-hit rhododendrons such as 'Maximum Roseum'.

Wait Before Pruning or Tossing
Both nursery owners plan to watch and wait till mid or late June to see if and where the shrubs resprout or leaf out. "Where there's dieback, I usually wait to see if there's any growth at all, then I cut back to good wood," said Gears.

I concur. On a recent visit to the distressed camellias, the brown leaves had dropped. Shiny, new, green leaves were filling out the branches; new buds were swelling on the stem tips.

Rhodie Planting Tips
When you transplant a rhodie or azalea, Brouse advises removing from one-third to one-half of the potting media from the roots to loosen them. Plant in native soil enhanced with peat moss but lean on fertilizer.


Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!

GardeningwithKids.org Catalog

Special Report - Garden to Table

— ADVERTISEMENTS —