Caring for Forsythia
Complete guide — Forsythia x intermedia
forsythia needs low maintenance, a position in full sun or partial shade on loam / clay soil / chalky soil and moderate.

Position
full sun, partial shade
loam, clay soil, chalky soil
moderate
Feeding
Feed in March and April.
Year-round care
Forsythia has moderate water needs and tolerates short dry spells once established, but water during prolonged dry periods in spring and summer, especially in the first two years. A thorough soak every ten days is better than frequent shallow watering. Reduce watering in autumn and winter when the plant is dormant and rainfall usually suffices. Feed in March or April as growth resumes. Scatter a general-purpose granular fertiliser such as Growmore or blood, fish, and bone around the base at the rate recommended on the packet, then water in if rain isn't forecast. A second, lighter feed in late April can boost flowering the following year, but forsythia is not a heavy feeder and will perform adequately in average soil without much intervention. Refresh the mulch layer each spring to suppress weeds, conserve moisture, and gradually improve soil structure as it breaks down. Keep mulch a few centimetres away from the stems. Forsythia is generally pest- and disease-free. Occasionally you may see aphids on soft new growth in late spring; a strong jet of water usually dislodges them, or leave them for natural predators. Forsythia gall, caused by a bacterium, produces rough swellings on stems but is uncommon and rarely serious—prune out affected growth if it appears. This shrub is fully hardy across temperate Europe (zone 5a–8b) and needs no winter protection. Maintenance is genuinely low: an annual prune, a spring feed, and occasional watering in dry weather are all it asks.