05/02/02

Tree peonies have a lot going for them. They are beauti ful, easy to grow and won't even grumble if you put them in clay soil - so long as it is well-drained.

And, they'll get by with four hours of sunlight a day.

Delicate crepe paper-like petals on richly colored flowers, 6 to 10 inches in diameter, may last 10 to 14 days. A mature plant may have 150 flowers.

"Tree peonies can generally live 150 to 250 years," said Michael Hsu of Peonyland Farm in Richlandtown, Pa. "The oldest one I saw in China was 400 years old."

They are the only crop that Hsu grows on his farm. Plants from Peonyland will be available at Holden Arboretum's plant sale Saturday and Sunday.

Tree peonies aren't really trees. They may grow as tall as 4 feet, but they are more like shrubs. They generally bloom in mid-May, a week or two before the herbaceous peonies.

Woody stems of tree peonies are visible in the winter, while the soft stems of herbaceous peonies, which are more frequently seen in landscapes, turn yellow after frost and die back to the ground.

Although gardening books and experts say fall is the best time to plant tree peonies, not to worry. Hsu's plants are in containers and may be planted at any time during the growing season.

"If I can grow them, anyone can," said Hsu, who is in the consulting business with his father.

Hsu said that four years ago, they had zero horticultural knowledge, but they quickly learned by consulting experts. He and his father were driving through Bucks County, Pa., when they saw a farm for sale. They bought it, then had to decide what to do with it.

"I didn't want to mow lawn, and we didn't want to become corn or soybean farmers," Hsu said.

"Grow flowers," said his mother.

The Hsus settled on tree peonies because they are the national flower of China. "We imported 60,000 tree peonies from China," Hsu said.

They now have a farm in China, where they grow their own. Plants are started by root division, grown in China for two years, then shipped to Pennsylvania and grown at Peonyland for two years before they are mature enough to sell.

"This is our fourth year in business and our second year of selling peonies," Hsu said.

These tree peonies are grown on their own roots, rather than grafted. "A grafted plant may not bloom the second, third or fourth year," Hsu said.

"After the first year in the ground, you can ignore them," Hsu said. He recommends fertilizing the first year when the buds begin to open in late winter with a low nitrogen high phosphorous fertilizer. A 10-30-10 is best for flower growth and root growth, Hsu said.

After the flowers have bloomed and been deadheaded, fertilize again to encourage more root growth, Hsu said.

"Tree peonies were destroyed during the cultural revolution because they are symbols of royalty and prosperity," Hsu said. "It took a long time for China to get the tree peony industry back on track."

Because they are slow-growing, tree peonies are more expensive than herbaceous peonies. Tree peonies shouldn't cost more than $75, Hsu said, except for rare varieties, which may be around $150.

Hsu recommends "Hermosa Red," one of the fastest-growing and least expensive.

His favorite is "Twin Beauty," which has all-pink and all-purple flowers on one plant.

Contact Suzanne Hively at: