Kris Bachtell’s Advice for Donors Shopping at the Plant Sale

Donor gardeners rejoice when they gather for their special preview of the Arbor Day Plant Sale at The Morton Arboretum each April. Kris Bachtell, vice president of collections and facilities, is always on hand as a Plant Genius to answer donors’ questions while they shop. Here is some of his top advice for gardeners at this year’s preview event, being held Wednesday, April 27.

Think in layers. Imagine your garden the way landscape designers do, with not just the ground level of perennials and ground covers, but a midlevel of shrubs and taller grasses, and a top level of trees. Since taller plants are also likely to be wider plants, it’s important to allow enough room horizontally. “Make sure your beds are all at least 5 feet wide,” Bachtell says. “That gives you the ability to layer.” Good news: You can find plants for every layer at the plant sale.

Use a variety of plants for separation. “Tall evergreens aren’t the only plants you can use for screening or to create garden rooms,” Bachtell says. Consider shrubs: “A hedge doesn’t have to be all one kind of plant,” he says. “It can combine evergreens, flowering shrubs, and shrubs for fall color.” Ornamental grasses can provide screening in the summer when they are tall. Or use a trellis with vines, such as the clematis that have been planted to climb trellises in the new Grand Garden. All these kinds of plants will be available at the sale.

Plant perennials in containers. “Plant a hosta or heuchera in a pot, and water and fertilize it the way you would flowering annuals, and it can be spectacular,” he says. At the end of the growing season, transplant these perennials into an appropriate spot in your yard. Shrubs or small trees, such as Japanese maples, can also be planted in containers if you have a sheltered but unheated place to overwinter them and protect their roots. The container gardens at the Arboretum are all designed around potted trees and shrubs that are grown this way.

Choose native plants thoughtfully. Native plants are increasingly popular, in large part because they support native insects and other wildlife. Bachtell urges gardeners to consider not just the straight natural species of native plants, but so-called “nativars”—selections or hybrids of native plants that may offer advantages for a home landscape. For example, they may have a more compact form, more reliable performance, or a longer bloom time. “Tallgrass prairie plants are often too tall and floppy for a garden,” he says, “but there are cultivars of those plants that are shorter and easier to use.” Both straight-species native plants and nativars will be available at the sale. “Even some non-native plants such as panicled hydrangeas can be amazingly good nectar and pollen sources for native insects,” he says.

Get great tomatoes. Among the popular offerings at the sale are grafted tomatoes—flavorful heirloom varieties that have been grafted onto disease-resistant rootstocks. “Because of the disease resistance, the root system is so good that the plant is more healthy and it produces great yields,” he says. Arboretum staff raise the plants from seed—both the rootstock and the heirloom varieties—and do the grafting.