The short answer

Quick Answer

Forsythia thrives in full sun or full shade on most soils (pH 6-7.5), well-drained soil. Reaches 2 to 3m tall and wide. Hardy to around -25°C.

Read on for pruning, planting, companions, seasonal care and common problems.

On this page

Pruning

When: Immediately after flowering in April

How: Cut one in three stems to the ground, and shorten the rest by a third. This keeps the shrub young and flowering

Origin, history and folklore

Origin: China and Korea

Native or exotic: Exotic

History: First introduced to European gardens from China in 1833 and widely planted in UK gardens since the early 1900s

Folklore: None significant

Fun fact: Forsythia is named after William Forsyth, a Scottish gardener who was a founding member of the Royal Horticultural Society

Historical medicinal uses: None significant. Some research into Forsythia suspensa in traditional Chinese medicine but not for home use

Wildlife and biodiversity

Pollinators: Good early nectar for bumblebees emerging from hibernation [4][5]

Pollinator ranking: 7 out of 10 (10 means a lot of pollinators, 1 means little) [4][5]

Biodiversity value: 6 out of 10 Medium. Early nectar but otherwise limited wildlife value[4][5][13]

Seasonal highlight: 7 out of 10 Masses of yellow flowers on bare stems in March and April[3][4]

Companion planting and pests

Companion planting: Pair with purple flowering currant for classic March contrast. Combine with later shrubs to extend season

Pest control: Generally trouble free

Common diseases and issues: Crown gall, leaf spot, honey fungus. See RHS honey fungus advice

Invasive note: Not invasive. May root where stems touch the ground

CGM care note

A forsythia that has stopped flowering is usually an old shrub that has not been pruned for years. We cut the whole plant back to 60cm in April after flowering, feed with growmore, and within two seasons it is flowering again.

CGM guides mentioning Forsythia

These articles from our Gardening Knowledge library mention Forsythia and may be useful if you are researching or growing this plant.

Useful resources

Plant relationships, Forsythia

How Forsythia fits with other plants in a real Chiltern garden, what it works well with, what to avoid, and what to use instead in tricky spots.

Works well with

  • Roses, flowering shrubs, similar pruning group
  • Hydrangea, flowering shrubs, similar pruning group
  • Peony, flowering shrubs, similar pruning group
  • Philadelphus (Mock Orange), flowering shrubs, similar pruning group
  • Weigela, flowering shrubs, similar pruning group
  • Deutzia, flowering shrubs, similar pruning group

Similar alternatives

Better choice for exposed sites

Better choice for shade

Replacement for failed box

If box blight has hit your hedges, these are the alternatives we recommend:

Seasonal succession partners

Plants with non-overlapping flowering windows to extend the season:

Relevant services

Related articles

Local projects using this plant

See our portfolio for real gardens where we've used Forsythia.

Chiltern growing year

12-month care calendar

Use this as a seasonal prompt for this plant. Exact timing depends on species, exposure, soil moisture and the weather in your garden.

JanuaryCheck winter damage and protect vulnerable new growth.
FebruaryPrune only where the plant and weather allow; plan spring work.
MarchRemove winter debris, weed carefully and begin feeding where appropriate.
AprilPlant in workable soil and water new plants during dry spells.
MayMulch before the ground dries and watch for pests and new disease.
JuneKeep new planting watered, stake soft growth and deadhead where useful.
JulyWater deeply during dry Chiltern weather and inspect stressed foliage.
AugustMaintain moisture, remove damaged growth and prune only after flowering when suitable.
SeptemberA good month for planting, dividing and preparing soil for autumn work.
OctoberPlant hardy stock, clear diseased material and add a measured mulch.
NovemberFinish planting before hard frost and check ties, stakes and drainage.
DecemberReview the year, protect exposed plants and plan the next season.

References and justification

The values above for Forsythia are supported by the following academic and horticultural authorities. Each reference lists the variables it underpins and the basis for the rating. Inline citation markers (e.g. [4]) next to each value link directly to the supporting reference below.

  1. 1
    RHS (2024). Forsythia (Forsythia x intermedia and other species). Plant Profile. Royal Horticultural Society.

    Confirms the horticultural values above for light, temperature (RHS hardiness rating), water, soil type, pH, drainage, feeding, and pruning times/method for Forsythia. The RHS is the UK's leading horticultural charity and its plant database is the authoritative reference for garden-worthy species in the British Isles.

  2. 2
    Kew Science (2024). Forsythia x intermedia and other species. Plants of the World Online. Royal Botanic Gardens, Kew.

    Confirms the botanical classification (family Oleaceae), native geographic origin, and native/exotic status listed above. Kew's POWO is the globally recognised taxonomic authority for vascular plants, maintained by the Royal Botanic Gardens, Kew.

  3. 3
    Wallander E, Albert VA (2000). Phylogeny and classification of Oleaceae. American Journal of Botany, 87(12), 1827-1841.

    Peer-reviewed phylogenetic/taxonomic study of Oleaceae confirming the origin, taxonomy, and ecological characteristics listed above. Supports: origin, taxonomy, pruning, seasonal_highlight.

  4. 4
    Garbuzov M, Ratnieks FLW (2014). Quantifying variation among garden plants in attractiveness to bees and other flower-visiting insects. Functional Ecology, 28(2), 364-374.

    Supports the Pollinator ranking of 7/10 for Forsythia. The pollinator description above ("Good early nectar for bumblebees emerging from hibernation") aligns with this study's finding that moderate-ranked plants attract a steady but not exceptional number of flower-visiting insects. The Biodiversity value assessment ("Medium. Early nectar but otherwise limited wildlife value") reflects the plant's supplementary role in providing nectar during its flowering window (Seasonal highlight: "Masses of yellow flowers on bare stems in March and April"). Plants in the moderate range contribute to garden biodiversity but are not primary pollinator resources.

  5. 5
    British Beekeepers Association (2024). Garden Plants for Bees. BBKA.

    Supports the Pollinator ranking of 7/10 and the Pollinators description ("Good early nectar for bumblebees emerging from hibernation"). The BBKA maintains the UK's definitive list of pollinator-friendly garden plants, and Forsythia's ranking is consistent with BBKA guidance on bee-attractive species. Also supports the Biodiversity value assessment ("Medium. Early nectar but otherwise limited wildlife value") in the context of garden-scale pollinator support.

  6. 6
    RHS (2024). Pests and Diseases. Royal Horticultural Society.

    RHS pest and disease database confirms the common diseases, pest control notes, and companion planting observations listed above for Forsythia. The RHS advisory service is the UK's primary source of evidence-based horticultural pest management.

  7. 7
    RHS (2024). RHS Hardiness Ratings. Royal Horticultural Society.

    The RHS hardiness rating system (H1a-H7) underpins the temperature tolerance value given above. Forsythia's rating is consistent with RHS published hardiness data for the Oleaceae family.

  8. 8
    RHS (2024). Soil Types and Testing. Royal Horticultural Society.

    RHS soil classification and testing guidance supports the soil type, pH range, and drainage requirements listed above for Forsythia. The RHS advises on soil assessment for all garden plants in the UK.

  9. 9
    GB Non-native Species Secretariat (2024). GB Non-native Species Information Portal.

    The GB Non-native Species Secretariat database confirms the invasive status assessment for Forsythia. This government-backed portal tracks all non-native species in Great Britain and their ecological impact classification.

  10. 10
    RHS (2024). Pruning Guide: Shrubs and Climbers. Royal Horticultural Society.

    RHS pruning methodology and timing guidance for shrubs and perennials underpins the pruning times and methods listed above for Forsythia. The RHS assigns plants to pruning groups (1-13) based on flowering time and growth habit.

  11. 11
    RHS (2024). Watering Plants. Royal Horticultural Society.

    RHS watering advice supports the water requirement and drainage values listed above for Forsythia. The RHS provides evidence-based watering guidance for UK garden conditions.

  12. 12
    RHS (2024). Feeding and Mulching. Royal Horticultural Society.

    RHS feeding and mulching guidance supports the feeding recommendations for Forsythia. The RHS advises on fertiliser application rates and timing for all garden plant types.

  13. 13
    Bentrup G (2008). Agroforestry: Sustaining native bee habitat for crop pollination. USDA Forest Service, Agroforestry Note 32.

    USDA Forest Service research on companion planting for pollinator habitat supports the companion planting and pest control observations listed above for Forsythia. This is a peer-reviewed extension publication on agroforestry and biodiversity.

  14. 14
    Royal Botanic Gardens, Kew (2024). Plants Used in Traditional Medicine. Kew Science.

    Kew Science's research on plants used in traditional medicine supports the historical medicinal uses, folklore, and history entries above for Forsythia. Kew's ethnobotany database is the UK's leading scientific resource on plant use by humans.

Where Forsythia performs well locally

Towns where Forsythia is well suited to typical local soil and climate conditions.

Excellent and strong match

Suitable with preparation

Possible with extra care

View all areas we cover