Forsythia viridissima

Greenstem Forsythia
 

Mature Size, Growth, Longevity

Gets 6-10' tall and wide, with a stiff, upright, somewhat flat-topped habit. Moderate growth rate.

Native Range

Native to China. Introduced in 1844 by Robert Fortune.

Flower and Fruit Details

Flowers are bright yellow or tinged with green, 1" long, March-April, borne singly or with 2-3 together. Flower buds may be killed at -15 to -20 degrees F, although such temperatures do not damage the stems or leaf buds. Fruit is a small, brown capsule, not showy.

Leaf and Bark Features

Deciduous: Leaves are opposite, simple, with entire margins, or toothed near the tip, about 1-4" long and 3/4-1 1/2" wide, sometimes 3-parted, dark green, elliptic-oblong to lanceolate, with a petiole 1/4-1/2" long. Little fall color. Young stems greenish, with chambered pith, changing to excavated pith on older stems.

Culture and Care

Needs full sun (best) to part shade. Tolerates deer, clay soil, urban conditions and juglone in soil from nearby black walnut trees. Avoid low, wet areas if possible. May be pruned to the ground after flowering every few years to rejuvenate, if desired Zone 5-8 No serious insect or disease problems.

Strengths, Weaknesses, Other Facts

3-season interest: Spring, summer and fall. This is one of the parents of the popular Border Forsythia. Forsythia is named for William Forsyth, 1700's Scottish author and superintendent of the Royal Gardens of Kensington Palace. "Viridissima" means "very green".

Suggested Uses

Used for hedges and screening, and for cut flowers.

Taxa and Plants of this Species at BCA

The following taxa are (or were) represented in the collections at Boone County Arboretum. Additional taxa may be available in the trade that are not included here.

  • Forsythia viridissima 'Bronxensis' // Bronx Greenstem Forsythia
    Shrub. A low, spreading, flat-topped cultivar. Leaves ovate, bright green, serrated, 3/4-1 3/4" long. Grows to 12" tall and 2-3' wide. The primrose light-yellow flowers are 1" long, occur in late March to April, 1-3 together. Bark is often greenish. Often used as a foundation plant. Grows well in landscape plantings and in containers. Good groundcover for slopes and embankments.
    -- not currently in our collection --

  • Forsythia viridissima 'Gold Tide' // Gold Tide Greenstem Forsythia
    Shrub. Also known as 'Courtasol'. Zone 5-8. Bright yellow flowers, before the leaves, in early spring (Mar-Apr). This is a dwarf cultivar, known for its spreading, yet compact, semi-arching growth habit. It gets 1-2' tall and 2-4' wide. A fast grower. Great for containers, a low hedge, or in mass plantings, foundation plantings, woodland gardens, cottage gardens, Asian/Zen gardens, rustic gardens or cutting gardens. Deer resistant. Tolerates clay. Resistant to juglone in soil from nearby walnut trees. Needs full sun/light shade. Ovate, medium-green leaves. Fall color not significant. 'Gold Tide' is the result of experiments in France, grown from seeds of a Spring Glory Border Forsythia plant that was irradiated w/ gamma rays. Patented in 1995.
    Bed 58

  • Forsythia viridissima var. koreana 'Kumson' // Kumson Greenstem Forsythia
    Shrub. Variegated leaves have silvery-yellow veins, with green between the veins, causing a silvery, net-like variegated pattern.. The variegation is dramatic on young leaves, but is lost with age, or in the shade, where leaves revert back to more solid green. So, even though this variety is more shade tolerant than others, full sun is needed to best maintain the leaf variegation, & to enhance flower production. Normally 4-6' tall & wide (rarely 6-8' tall). Fall foliage may have shades of purple, green & white. Arching, deep purple winter stems after leaves have fallen. Also known as 'Kumsum'. Good for hedging or screening. Stems of flowers make good cut flowers. Zone 5-8. Deer resistant. Needs full sun to part sun. Avoid low, wet areas.
    Bed 59