Show Off forsythia

Sun

Full sun for the most flowers; tolerates partial shade but flowers less densely.

Water

Water regularly during establishment. Once established, water deeply during prolonged dry spells; avoid persistently wet soil.

Soil

Average, well-drained soil, including clay that does not remain waterlogged; tolerates acidic, neutral and alkaline conditions.

Height

5-6 ft (1.5-1.8 m)

Spread

5-6 ft (1.5-1.8 m)

Flowers

Bright yellow flowers in early to mid-spring, usually before the leaves emerge.

Foliage

Opposite, pointed green leaves with toothed edges; autumn colour is variable and often unremarkable.

Growth

Moderate to fast

Care needed

Low

• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   2.6 ft (0.79 m)

3. After 2 years

   4 ft (1.1 m)

4. After 3 years

   4 ft (1.4 m)

5. After 5 years

   5 ft (1.7 m)

   full size

About 4 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Fast

• Water deeply whenever the root zone begins to dry during the first growing season.
• Spread 2-3 in (5-8 cm) of organic mulch over the roots, keeping it clear of the stem bases.
• Apply compost in spring; use a balanced fertiliser only if growth is weak or the soil is poor.
• Allow room for its mature width rather than relying on repeated clipping.
• Avoid high-nitrogen lawn fertiliser around the roots, which can encourage leafy growth at the expense of flowers.

Pruning. Prune just after flowering, removing dead wood and, when needed, up to one-third of the oldest stems at ground level. Shorten awkward shoots selectively; autumn or winter pruning removes the following spring's flower buds.

Late winter

Check for broken branches, but leave healthy stems untrimmed to preserve flower buds.

Early spring

Plant container-grown shrubs when the soil is workable and neither frozen nor waterlogged.

Spring

After flowering, thin old stems if needed and refresh the mulch.

Summer

Water young plants during dry weather and check that surrounding plants are not crowding them.

Early autumn

Plant in mild regions while the soil is still warm, allowing time for roots to establish.

Late autumn

Water before the ground freezes if autumn has been dry; avoid routine pruning.

• Plant as an informal flowering hedge where its full width can develop without shearing.
• Use behind spring bulbs so yellow flowers rise above daffodils, grape hyacinths or blue squills.
• Place against a dark evergreen background to make the bare-stemmed flowers stand out.
• Include in a mixed shrub border with later-flowering shrubs that take over after its spring display.

Garden styles it suits: Cottage garden, English country, Traditional, Farmhouse, Low-maintenance and Family-friendly.

Plant it with: Daffodils, Grape hyacinths, Siberian squill, Hellebores, Catmint and Panicle hydrangea.

Wildlife: The branching growth provides cover for small birds. Insects may visit the flowers, but it is not a particularly rich nectar or pollen source.

• Few flowers: provide more sun and prune only immediately after flowering; excessive nitrogen can also reduce bloom.
• Winter-damaged flower buds: severe cold can kill buds while the shrub survives; choose a sheltered position and avoid frost pockets.
• Root rot in wet soil: improve drainage or move the plant to a better-drained site; do not keep the root zone saturated.
• Stem galls or dieback: cut affected stems back into healthy wood, disinfect tools between cuts and discard infected material.

Not known to be toxic to people, cats, dogs or horses. No part is recognised as a significant poisoning hazard, but it is not an edible plant and eating plant material may cause stomach upset.

• Lynwood forsythia (Forsythia × intermedia 'Lynwood Variety')

  Usually grows substantially taller and broader than Show Off. Young plants can be difficult to distinguish reliably without a cultivar label.

• Weeping forsythia (Forsythia suspensa)

  Has long, strongly arching or trailing stems that may root where they touch the ground, rather than Show Off's more compact, upright framework.

• Winter jasmine (Jasminum nudiflorum)

  Has slender green stems and yellow flowers with usually six lobes; forsythia flowers have four lobes and grow on woody brown stems.

Forsythia honours Scottish horticulturist William Forsyth, while × intermedia refers to its hybrid origin between two species.

Propagation. Softwood cuttings in late spring or early summer, or hardwood cuttings during dormancy, preserve the cultivar's characteristics. Check current plant breeders' rights or patent restrictions in your country before propagating it.

Accepted botanical name

Forsythia intermedia

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.