After a cold, dreary winter, forsythia signals spring with a generous cascade of bright yellow flowers. Depending on the spring weather, they flower any time from mid-March to mid-April.
Most forsythias are native to east Asia, although one species hails from southern Europe. They range in size from 18 inches to 10 feet or more in height. Forsythia grows in full sun to part shade, but more sun produces better flowering. Flower color varies from a pale primrose yellow to a rich buttery gold. These carefree shrubs will grow in almost any soil type as long as it is not extremely dry. A bonus—deer tend to leave them alone.
Meet Some of the Garden's Forsythia
The Garden’s collection includes many forsythia species and cultivars. A cultivar is a plant developed through breeding for particular characteristics such as color, scent, size, or shape.
Girald forsythia (Forsythia giraldiana) is a large species from northwestern China where it grows in open woodlands, rocky slopes, and bottomlands. Arnold Dwarf is a low-growing hybrid of Forsythia x intermedia and Forsythia japonica var. saxatilis. This rugged ground-covering shrub grows to 3 feet tall by 6 to 7 feet wide. See specimens just east of Annex buildings 1 and 2. The charming Forsythia x intermedia 'Beatrix Farrand’ also grows in this area.
Plant breeders in New Zealand created ‘Fiesta,’ which boasts colorful foliage. The leaves start out creamy yellow with a green edge and become green with white veins as the season progresses. You can find plants along the trail near parking lot 6. The exceptionally hardy Forsythia ‘Meadowlark’ grows in the Malott Japanese Garden and near the Dwarf Conifer Garden.
Older varieties, such as ‘Lynwood’, are hardy in the Chicago area, but the flower buds can be damaged by extreme cold in winter. Forsythia ‘Northern Gold' was developed in Canada and the flower buds can withstand temperatures of minus 30 degrees Fahrenheit. In late winter, bring a few forsythia branches indoors to coax them into early bloom. See how it’s done.
Gardening with Forsythia
Many forsythias tend to be large, vigorous shrubs that need plenty of space. They often look good planted in a border mixed with other shrubs or massed together. When planting a single shrub, give it plenty of room. If its mature size is 8 to 10 feet wide and it’s planted 2 or 3 feet from a path or a foundation, you’ll be doing unnecessary pruning to keep it in bounds.
Forsythia develops next year’s flowers on this year’s branches. Pruning should be done right after the shrub is finished flowering. If you wait too long, you’ll remove the buds and the flower show for next spring. Don’t prune the shrub into a circle or a rectangle or you’ll lose the graceful arching branches. Plants that are overgrown or have many dead stems can be pruned heavily by removing all the branches to about 8 inches above the soil. This can be done in early spring; flowering will take place the following year. To keep the plant looking good, prune 1/3 of the oldest canes at ground level immediately after flowering.