When and how do I sow nasturtium seeds?

Direct outdoors from May, after the last frost. The seeds are large and easy to handle. Push 2 cm into the ground, 30 cm apart for climbing varieties, 20 cm for bush types. Water in. Germination in 7–14 days. Don't bother starting indoors — nasturtiums hate transplanting and root-disturbance.

Why is my nasturtium all leaves and no flowers?

The soil is too rich. Nasturtiums flower on lean, poor-to-average soil; rich beds give a riot of foliage and almost no flowers. Don't dig in manure before sowing; don't feed during the season; in containers, use peat-free compost without added feed. The plant wants to be slightly under-cared-for.

Are nasturtiums edible?

Yes — every part above ground. Flowers are mild, peppery, look beautiful in salads and ice cubes. Leaves taste like rocket — peppery, zingy, good in sandwiches and salads. Young green seed pods pickled in vinegar give poor man's capers — startlingly like the real thing. Pick young leaves and flowers; older parts toughen. Don't eat sprayed plants.

Climber or bush — which type should I choose?

Climbing (Tall Mix, Jewel of Africa) for 2 m of quick cover on fences, walls, wigwams; useful as a screen or for filling gaps in roses. Bush (Tom Thumb, Empress of India, Black Velvet) for containers, edges, the front of borders, and ground cover. Both have the same flowers, just different habits. Grow both for variety.

Do nasturtiums really help with aphids?

Yes, as a trap crop. Aphids (especially blackfly Aphis fabae) prefer nasturtium foliage to most other plants and concentrate on it. Planting nasturtiums beside vulnerable crops (beans, brassicas, courgettes) draws aphids onto the decoy and away from your dinner. You can then ignore the nasturtium aphids, hose them off, or feed them to encouraged ladybirds.

How do I make nasturtium poor man's capers?

Pick young green seed pods (still soft, before turning yellow). Soak in salted water overnight; drain. Pack into a sterilised jar; cover with hot white wine or cider vinegar; add a few peppercorns and a bay leaf. Seal. Mature for at least a month before eating. Use anywhere you'd use capers — they're remarkably similar in flavour.

Capuchinha

Tropaeolum majus

Sow nasturtium seed direct from May, after the last frost — the seeds are large, easy to handle, and the plants hate transplanting. Nasturtiums are frost-tender annuals (RHS H1c) but ridiculously easy: push a seed 2 cm into the ground, water in, and the plant does the rest. Climbing varieties (Tall Mix, Jewel of Africa) scramble 2 m up netting or wigwams; bush forms (Tom Thumb, Empress of India) make compact mounds 30 cm tall. The flowers, leaves and young seed pods are all edible — peppery, like rocket. Nasturtiums also work as a trap crop for blackfly, pulling aphids away from beans and brassicas. Don't over-feed; rich soil gives leaves and no flowers. Self-seeds happily in mild gardens.

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