Grow Nasturtiums: Easy Tips for Peppery Edible Flowers and Leaves

Grow nasturtiums for bright, edible flowers and rounded leaves with a peppery, watercress-like flavor. These easy annuals thrive in warm weather, tolerate lean soil, and need little care once established. Choose compact plants for pots or trailing varieties for hanging baskets and garden edges, then sow the large seeds outdoors after frost has passed.

Choose a site and variety

Nasturtiums grow best in full sun, generally six or more hours of direct light a day. In hot climates, a little afternoon shade can help plants cope with summer heat. They prefer well-drained soil and can flower especially well in poor to moderately fertile ground. Rich soil and heavy fertilizer often produce abundant leaves at the expense of flowers.

Plant form varies by cultivar. Compact or dwarf types make tidy mounds in borders and containers. Trailing varieties spread across the ground, spill over pot edges, or climb short supports. Check the seed packet for the plant’s mature size and habit; “nasturtium” can refer to both compact and vigorous plants.

Sow nasturtium seeds after frost

Nasturtiums dislike cold, so wait until the danger of frost has passed and the soil has warmed. Direct sowing is usually easiest because the plants do not always respond well to having their roots disturbed during transplanting.

Plant nasturtium seeds about ½ to 1 inch deep, following the packet’s spacing guidance. A spacing of roughly 10 to 12 inches suits many varieties, though trailing plants may need more room. Water the soil after sowing and keep it lightly moist while the seeds sprout.

Nasturtium germination commonly takes about 7 to 14 days in warm soil, though conditions and seed freshness affect timing. The seeds have a hard coat. Soaking them in water overnight before planting may help them absorb moisture and sprout sooner, but it is optional. If you start seeds indoors, use individual pots and transplant carefully while seedlings are small.

Care for plants as they grow

Established nasturtiums need regular water during dry spells, especially in containers. Let the soil begin to dry between waterings, but do not let plants wilt repeatedly. Poor drainage can lead to root problems, so use pots with drainage holes and avoid keeping the soil soggy.

Nasturtium poor soil is often better than overly rich soil for flowering. Skip routine feeding unless plants are growing weakly in very poor ground or a container mix has become depleted. If plants make lots of foliage but few flowers, reduce fertilizer and check whether they are receiving enough sun.

The plants usually need little pruning. Trim stems that grow beyond their allotted space, and remove faded flowers if you want to limit seed formation and encourage continued blooming. Leaving some flowers to form seed pods can provide seeds for planting next season.

Grow nasturtiums in containers

Nasturtium containers work well on sunny patios, balconies, and steps. Choose a pot with drainage holes and a standard potting mix. Compact varieties suit smaller containers; trailing varieties look good in hanging baskets or pots where their stems can spill over the sides.

Containers dry faster than garden beds, so check the soil regularly in warm weather. Water when the surface feels dry, allowing excess water to drain away. Avoid oversized pots filled with very rich soil, which can encourage leafy growth and hold more moisture than the plants need.

Harvest edible nasturtium flowers and leaves

Harvest flowers and leaves from plants grown without pesticides or other products not approved for edible crops. Pick them when fresh, and rinse gently under cool water before using. The flavor is peppery, with younger leaves often milder than older ones.

Pick fully open flowers for salads, sandwiches, or as a colorful garnish. Use nasturtium leaves much as you might use watercress or arugula, in salads, wraps, or as a finishing addition to a dish. Add flowers and leaves near serving time; heat can dull their texture and flavor. Take only a few leaves from each plant at once so it can continue growing.

Unripe green seed pods are also edible and can be pickled as a caper-like condiment. Harvest them while they are still small and tender. Keep fresh flowers and leaves cool and use them soon after picking, since they wilt quickly.

Nasturtiums often produce seed pods late in the season. Let pods dry on the plant until they turn brown, then collect and store them in a cool, dry place. In frost-free climates, nasturtiums may persist longer; where frost occurs, they are generally grown as annuals.