Greenstem Forsythia Plant Care

Greenstem Forsythia (Forsythia viridissima) belongs to the Oleaceae family within the Forsythia genus. Greenstem Forsythia is native to southern China and South Korea, and introduced to Japan and the United States. Greenstem Forsythia is also known as Chinese Forsythia.

Greenstem Forsythia displays an upright, arching shrub growth habit, reaching up to 8 ft tall with a spread of approximately 10 ft. Greenstem Forsythia produces bright yellow, bell-shaped flowers in early spring.

Leaf size: approximately 3 inches.

Water a young or newly planted Greenstem Forsythia every 7–10 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established trees mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Greenstem Forsythia thrives in full sun to partial shade.

Forsythia viridissima tolerates temperatures of 10–90°F. Greenstem Forsythia prefers humidity levels of 40–70%.

Well-draining, fertile soil with a mix of compost and sand. Good drainage is essential for Greenstem Forsythia to prevent waterlogging, which leads to root rot and fungal issues.

Feed Greenstem Forsythia every 6 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established trees in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun to partial shade and well-draining, fertile soil with a mix of compost and sand. Avoid low spots where water collects after rain.

Greenstem Forsythia is suited to USDA Zone 5a – 8b.

Plant container-grown or balled-and-burlapped trees in spring or early autumn, setting the root flare at soil level, and water well after planting.

Greenstem Forsythia can spread to about 10 ft (3 m) and reach about 8 ft (2 m) tall. Space plants about 10 ft (3 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the tree spacing calculator.

Prune Greenstem Forsythia while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the tree in one year.

Greenstem Forsythia is hardy down to USDA zone 5a, so once established it can stay outdoors through winter in that zone and warmer ones.

Water deeply in late autumn before the ground freezes, and spread a 5–8 cm (2–3 in) layer of mulch over the root zone, keeping it away from the trunk.

Young and container-grown trees need extra protection: roots in a pot freeze much more easily than roots in the ground.

Greenstem Forsythia can be propagated through softwood cuttings, hardwood cuttings. Similar propagation techniques also apply to european forsythia plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Greenstem Forsythia is susceptible to aphids, scale insects, spider mites. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Greenstem Forsythia grows outdoors in USDA Zone 5a – 8b. It survives winters down to planting zone 5a. Greenstem Forsythia is native to southern China and South Korea, and introduced to Japan and the United States.