How to grow nasturtiums

Nasturtium is a fast, sprawling warm-season annual grown as much for the plate as for the flower bed, since its leaves, buds, and blossoms are all edible with a sharp, peppery bite close to watercress. Gardeners tuck it along bed edges, into containers, or let a climbing form run up a trellis, and it fills in quickly from seed with little attention once the weather warms. Beyond the kitchen use, the flowers draw hummingbirds and butterflies and hold color from planting until frost, and its tolerance for poor soil makes it a common choice for a leftover corner of the bed.

The hardest part of growing nasturtium well is resisting fertilizer. North Carolina State Extension notes that feeding the plant increases foliage but decreases flowering, the opposite of what most other bedding plants reward. A second-year gardener who has learned to fertilize struggling annuals for a better bloom often does the same for nasturtium planted in a rich, amended bed, and ends up with a thick mound of leaves and almost no flowers all season. Leaving the soil lean, or skipping fertilizer entirely, is what keeps the plant blooming instead of just spreading.