How to Grow Nasturtium
Annual
Nasturtiums are easy, colourful hardy annuals with rounded leaves and bright, characterful flowers. Trailing, climbing and compact types make them wonderfully adaptable. They cope with modest soil, flower generously in sun, and their open blooms are popular with pollinating insects. Flowers and leaves are also a familiar edible garnish.
Planting
Sow nasturtiums directly where they are to grow from April to June, placing seeds about 2 cm deep and 20 to 30 cm apart. In colder parts of the UK, wait until May if the ground is cold and wet. For an earlier start, sow singly in pots under cover in April and plant out after hardening off. Choose a sunny or lightly shaded site with free-draining soil; overly rich ground encourages leaves rather than flowers.
Care
Water seedlings during dry weather until established, then water containers regularly and border plants only in prolonged drought. Do not feed heavily. Guide trailing stems into gaps or over the edge of a pot, but there is little need for pruning. Remove tired leaves and spent blooms if preferred, although plants will often continue flowering without much attention.
Bloom time
Nasturtiums normally flower from June to October, often until the first frosts. Early potted sowings may begin sooner in mild southern gardens, while direct-sown plants in northern or Scottish gardens tend to start later.
Garden uses
Use compact nasturtiums in pots, window boxes and border edges, and let trailing forms spill over walls or tumble through a sunny bed. They suit informal cottage-style planting and wildlife-friendly gardens. Their flowers and leaves can be used sparingly as a colourful garnish, after growing without chemical treatments.
Tips
Sow a few extra seeds to replace losses to slugs. Avoid moving established plants, as they dislike root disturbance. Save seed only from healthy, open-pollinated plants if you enjoy surprises, as named hybrids may not come true. Look for RHS Plants for Pollinators recommendations when choosing single-flowered forms.
Growing Nasturtium: frequently asked questions
How do I grow nasturtium in the UK?
Sow nasturtiums directly where they are to grow from April to June, placing seeds about 2 cm deep and 20 to 30 cm apart.
When does nasturtium flower?
Nasturtiums normally flower from June to October, often until the first frosts.
How do I care for nasturtium?
Water seedlings during dry weather until established, then water containers regularly and border plants only in prolonged drought.
General guidance for UK gardens. Timing and hardiness vary by region and season; the RHS or a local garden centre can advise for your area. Page updated 19 Sep 2026.