Border forsythia

Botanical data

Family

Oleaceae (Oleaceae)

Height

1.5–3 m

Width

1.5–3 m

Habit

Spreading

Growth rate

Fast

Position

Full sun, Partial shade

Soil

Loamy, Humus-rich, Sandy

pH reaction

pH 6–7.5

Moisture

Moderate

Bloom

March–April

Hardiness

USDA 5a–8b

Propagation

From cuttings, By layering

Characteristics

A spreading shrub with arching branches that become densely covered with yellow, four-petalled flowers in early spring. The lance-shaped green leaves develop only after flowering. It reaches 1.5–3 m in height and a similar spread, grows fast and after a few years forms a dense, dome-shaped mass. The shoots are stiff and upright at the base and arch over towards the tips; those that lie on the ground for a long time may take root, although this happens less readily in the hybrid than in its parent species Forsythia suspensa. The leaves are opposite, 3–10 cm long and toothed in the upper half; on vigorous young shoots they are sometimes three-lobed. Autumn colour is poor — the leaves usually fall greenish-yellow, in some cultivars with a purple flush. The flowers, borne in clusters of several, emerge from buds set the previous summer on the previous year's growth; the corolla is fused, split into four narrow, reflexed lobes, 2.5–3.5 cm across (up to about 4 cm in large-flowered cultivars) and scentless. The identifying feature is the sequence of events itself: peak flowering (March–April) falls on bare, leafless shoots. Its requirements are minimal — well-drained soil with a pH of 6.0–7.5 is enough, hardiness reaches zone 5a, and once established the shrub tolerates drought and air pollution well. Left unpruned, it gradually becomes congested in the centre and flowers only around the outside of the crown, while the oldest shoots flop sideways.

Popular cultivars

‘Spectabilis’

One of the oldest and most widely planted cultivars, introduced by the Späth nursery in Germany in 1906. Vigorous (2–3 m), with large (about 4 cm), brassy-yellow flowers whose lobes are narrow, reflexed and twisted at the tips.

‘Lynwood Variety’

A bud sport of Spectabilis, found in Northern Ireland. The flower lobes are broader and less rolled, and the flowers are evenly spaced along the whole length of the shoot; the habit is more upright, reaching about 2.5–3 m.

‘Week-End’

A French sport of Lynwood (breeder's name Courtalyn), reaching 1.5–2 m. Compact and upright at first, arching and spreading after a few years. Flowers abundantly even on young plants.

‘Goldrausch’

A German selection with large, late and long-lasting yellow flowers, set abundantly on one-year-old shoots. Vigorous, to about 3 m — planted as a specimen and for informal flowering hedges.

‘Minigold’

A dwarf cultivar, compact and densely branched, with small flowers with broad lobes, reaching about 1–1.5 m. For small gardens and low hedges, where a typical forsythia would be too large.

‘Golden Times’

A cultivar with golden-yellow leaves with a green centre, ornamental even after flowering; in autumn the leaves turn pink and purple. Grows fast and upright, to about 3 m. The leaves may scorch in strong sun — a sunny position with some shade around midday is best.

Growing and care

Companion plants

The evidence level indicates whether the relationship is backed by research, observation, or gardening tradition.

Diseases and pests

Toxicity

History and origin

Forsythia was named after William Forsyth, an 18th-century Scottish gardener. The popular hybrid form was raised in Germany in the 19th century and quickly became one of the most widely planted spring shrubs. Forsyth (1737–1804) was royal gardener at Kensington and one of the founders of what later became the Royal Horticultural Society; the genus name Forsythia was given in his honour in 1804 by the Danish botanist Martin Vahl — the year Forsyth died. The parent species reached Europe in the 19th century: Forsythia suspensa from East Asian gardens, and Forsythia viridissima was brought from China by Robert Fortune in the 1840s. The hybrid arose spontaneously in cultivation, in the Old Botanical Garden in Göttingen, where both species grew side by side; it was described by the German dendrologist Hermann Zabel in 1885, and the first named clones were introduced to the trade by the Berlin nursery Späth from 1899. In gardens the hybrid has almost entirely displaced both parent species. In Poland forsythia is among the most frequently planted shrubs in housing estates and along roads, and its flowering is popularly taken as the signal of early spring; in the German phenological calendar the start of forsythia flowering marks the beginning of the early-spring phase.

Uses

For gardens as a specimen plant, in groups, for informal flowering hedges, and as early-flowering branches cut for indoor arrangements. Choose a position in full sun — in partial shade the shrub still grows, but flowers noticeably more sparsely. Since it spreads to 3 m, plant it at least 1.5 m away from paths, fences and walls; in an informal hedge keep a spacing of about 1 m, and plant in autumn (September–October) or in early spring. It looks best at the back of a border or at the edge of a group of shrubs, where after flowering, as an ordinary green shrub, it stops drawing the eye; for the same reason combine it with later-flowering shrubs — lilac (Syringa vulgaris), spiraeas (Spiraea) or mock orange (Philadelphus). The classic colour combination is the yellow-laden branches of forsythia above blue bulbs flowering at the same time: grape hyacinths (Muscari), squills (Scilla) and glory-of-the-snow (Chionodoxa). Do not plant sun-loving perennials right at the base of the shrub — they will soon end up in shade. In urban plantings it works well as a solid mass of greenery; for covering banks, prostrate forsythia cultivars are a better choice. The flowers give pollinators only modest forage (low nectar value), so in a planting aimed at insects add goat willow (Salix caprea) or flowering currant (Ribes sanguineum), which bloom at the same time.

Trivia

• Forsythia branches cut in February and placed in water bloom indoors (a technique known as forcing), announcing spring.
• Forsythia belongs to the same family as lilac and olive (the olive family).
• Forsythia flowers are heterostylous: one shrub bears only long-styled flowers, another only short-styled ones (Spectabilis belongs to the first group, Lynwood Variety to the second). Because a single garden usually holds just one clone of the same cultivar, the flowers have no partner of the opposite style type and forsythias very rarely set fruit; this happens only when two cultivars of different types stand side by side.
• The common name "golden rain" is also used for laburnum (Laburnum anagyroides) — a tree with hanging chains of yellow flowers that is highly poisonous in all its parts. Forsythia is not a poisonous plant; when buying, it is worth going by the Latin name.

Frequently asked questions