In fall, gardeners often start thinking about perennials either because they want to add additional plants to their gardens or because they need to take at least some of them out of their garden beds.

Perennials are plants that don’t die after one season but continue to live year after year. The category actually includes trees, shrubs, lawns, hardy bulbs, some vegetables and houseplants, and a large number of plants that are grown for their ornamental flowers or foliage. Many of these ornamentals are called “herbaceous perennials,” meaning the tops of the plants die in fall and come up again in spring.

Plants that live through the winter are “hardy.”

Many people plant perennials thinking they can save themselves a lot of work in the future. Plant them once, and they’ll continue to come up. But perennials are not maintenance-free. They typically require feeding, staking, and cutting back after they bloom. Periodically, many of them also need to be dug up and divided.

“Usually I wait until we’ve had a heavy frost to start putting my garden to bed,” says Henrico Master Gardener Erica Gilliam.

Gilliam says she cuts some plants in her garden back while leaving others. “”It’s nice to get your garden cleaned up and looking better,” says Gilliam, “But I leave some things up like the purple coneflowers because the birds eat them.”

Gilliam also divides some of her perennials in fall, but tends to wait until spring for most. “The plants are smaller in spring, so it’s easier,” she says.

Perennials should be divided when they are dormant, according to the Virginia Cooperative Extension publication “Perennials: Culture, Maintenance and Propagation,” either “just before a new season of growth, or in the fall so they can become established before the ground freezes.”

Gilliam often shares plants with friends. “I’ve always heard that if you divide your plants and give them away to your friends, you can always go back to them if you lose your original plant,” she says.

“My friends shared a lot of plants with me,” says Gilliam. “In the first years, I used to have teas in my garden so my friends could come over and see their babies growing here.”

Gilliam calls her garden a “colonial friendship cutting-garden,” partly because many of the plants were given to her by friends, and partly because friends helped inspire the design.

“When we first moved here and friends came to visit, we took them to colonial sites around the state,” says Gilliam, “and I got interested in the gardens.” She was particularly inspired by Monticello, and today her garden includes many plants that would have been found in Thomas Jefferson’s gardens interspersed with modern cultivars.

“Something is usually blooming in my garden from February to November,” says Gilliam. “I like to cut them and bring the color into the house.”

Though most perennials bloom for only a few weeks, combining plants that bloom at different times ensures continuous blooms.

Gilliam says some of the blooms in her garden also remind her of family members. “My peonies came from my mother,” she says. “And the evening primroses.”