Forsythia

Forsythia is a genus of 11 accepted species of flowering, deciduous, perennial shrubs native to China, Japan, and southeast Europe. It is a member of the olive family (Oleaceae). The genus is named for William Forsyth (1737–1804), who was the Scottish superintendent of the Royal Gardens of Kensington Palace and author of A Treatise on the Culture and Management of Fruit Trees, which in its day was probably the most widely read work on the subject.

Forsythia is easy to grow and does best in loose, medium moisture, well-drained soils in full sun to part shade. Plants in full sun will produce more flowers earlier in the spring than plants in partial shade. Forsythia is a forgiving plant and tolerates average to poor garden soils, urban conditions, and drought. The shrub is winter hardy, but colder winters and temperatures below -5 degrees Farenheit may retard flower development. Forsythia can tend to grow wildly, but it can be pruned to keep the shrub's growth under control. Flowers appear on old growth, so pruning should be done immediately after spring flowering. If you prune it after mid-July, you will likely remove flower buds for the following spring. To rejuvenate an older plant, you can cut it back almost ground level. The plant can be propagated by rooting stem cuttings and some cultivars may sucker. Long branches that touch the ground may layer; these can be cut from the parent plant when they have sufficient roots.

Depending on the species, the mature height of a forsythia shrub ranges from 3 to 10 feet and all species produce beautiful yellow flowers in early spring. The flowers are produced on long, arching, stems before the plants leaf out. They are one of the earliest flowers to appear in spring. Stems and flowers are often cut and brought indoors to show that winter will soon be over. Forsythia flowers are heterostylous (long-style morphs mate with short-style morphs) and are thus self-sterile. Characteristics of the pith are important in distinguishing the species.

Forsythia is adaptable to many garden designs and themes, including but not limited to Asian, children’s, cottage, and winter gardens. 

Diseases, Insect Pests, and Other Plant Problems: No known diseases or insect pests. Some species of forsythia are susceptible to leaf spot or crown gall.