Nasturtiums (Tropaeolum majus) are among the most versatile flowers in the garden, combining brilliant blooms, edible flowers and leaves, and exceptional companion planting benefits in one easy-to-grow annual. Native to South America, they quickly became favorites in cottage gardens and kitchen gardens for their cheerful flowers in shades of yellow, orange, red, cream, and salmon.
Their trailing or bushy growth makes them equally suited to garden beds, containers, hanging baskets, and vegetable gardens. The nectar-rich flowers attract bees, butterflies, and hummingbirds, while the peppery leaves and blossoms bring fresh flavor and vibrant color to the kitchen.
Growing Guide
Timing
Direct sow nasturtiums outdoors after all danger of frost has passed and the soil has begun to warm. Because they grow quickly, direct sowing generally produces the healthiest plants.
For an earlier display, seeds may be started indoors about 2–3 weeks before the last spring frost in biodegradable pots to minimize root disturbance. Successive sowings into early summer provide continued blooms well into fall.
Sowing & Starting
Large seeds benefit from soaking in room-temperature water for 8–12 hours before planting to help soften the seed coat and encourage more even germination.
Sow seeds about ½–1 inch deep in prepared soil and keep evenly moist until seedlings emerge, usually within 7–14 days. Space compact varieties 8–10 inches apart and trailing varieties 10–14 inches apart, allowing room for vines to spread naturally.
Growing & Care
Grow nasturtiums in full sun to light afternoon shade in well-drained soil. They bloom most heavily in average or even relatively poor soils. Rich soil or excessive fertilizer encourages lush foliage at the expense of flowers.
Water regularly while plants establish, then during extended dry periods. Remove spent flowers to encourage continued blooming, or leave a few to mature if seed saving is desired.
Nasturtiums are outstanding companion plants in vegetable gardens. Their flowers attract bees and other pollinators, while the foliage often draws aphids away from nearby crops, making them a commonly used trap crop. They pair especially well with tomatoes, cucumbers, squash, brassicas, beans, and fruit trees while helping create a more diverse, beneficial insect habitat.
Harvesting
Grow nasturtiums in full sun to light afternoon shade in well-drained soil. They bloom most heavily in average or even relatively poor soils. Rich soil or excessive fertilizer encourages lush foliage at the expense of flowers.
Water regularly while plants establish, then during extended dry periods. Remove spent flowers to encourage continued blooming, or leave a few to mature if seed saving is desired.
Nasturtiums are outstanding companion plants in vegetable gardens. Their flowers attract bees and other pollinators, while the foliage often draws aphids away from nearby crops, making them a commonly used trap crop. They pair especially well with tomatoes, cucumbers, squash, brassicas, beans, and fruit trees while helping create a more diverse, beneficial insect habitat.
Nutrition & Uses
Nasturtiums are grown for their ornamental beauty, edible flowers and foliage, and exceptional usefulness in companion planting. The brightly colored blooms and tender leaves add a peppery flavor to salads, sandwiches, herb butters, vinegars, and garnishes.
Immature green seed pods are sometimes pickled and used as a substitute for capers. Beyond the kitchen, nasturtiums brighten vegetable gardens, containers, hanging baskets, and pollinator plantings while providing continuous blooms throughout the growing season.
Pests & Diseases
Nasturtiums are generally easy to grow but may attract aphids, flea beetles, caterpillars, slugs, or snails. Aphids commonly gather on the stems and undersides of leaves, making the plants useful as sacrificial trap crops in vegetable gardens.
Good air circulation, well-drained soil, and watering near the base of the plant help reduce leaf spots and mildew during humid weather.
Seed Saving
Nasturtiums are insect-pollinated and varieties may cross when flowering nearby. Grow one variety for seed or provide isolation if maintaining a particular type.
The large, three-part seeds form beneath spent flowers and change from green to tan as they mature. Pick them individually when they loosen easily, or place a tarp beneath the plants and shake mature vines to catch falling seed. Whole vines can also be cut and dried over a tarp or screen. Finish drying the seeds indoors until they are hard and fully dry before storing them in a cool, dark place. Seed Savers Exchange recommends allowing dry-fruited seed to mature as fully as possible on the plant before harvest.
Extra Tips
Soak seeds overnight for more even germination.
Avoid rich soil for the best flower production.
Excellent companion plant for vegetable gardens.
Harvest flowers regularly to encourage continued blooming.
Collect mature seeds from beneath the plants before prolonged wet weather.
