How to Grow Nasturtium
Learn how to plant and care for nasturtium, an old-fashioned, easy-to-grow garden favorite that's been in cultivation since the days of the Inca Empire.
Nasturtium flowers give your yard a casual, cottage-garden vibe. They look beautiful climbing a fence, tumbling out of a window box, or sprawling over the ground of a rock garden. A fence covered in nasturtium in brilliant yellow, red and orange blooms says “I want my garden to look joyously random, a reminder that nature's in charge, not man.”
Nasturtium aren't just pretty. You can eat them, too. Sprinkle the blooms, leaves or unripe seed pods into a salad to add a peppery, cress-like taste.
Here's what you need to know about growing nasturtium.
Nasturtium is native to Mexico and Peru, where the Inca and other native peoples ate the whole plant as a salad vegetable. Europeans brought nasturtium to the Old World in the 16th century and grew it for food as well as fragrance. Victorians used nasturtium in their tussie mussie bouquets, and they pickled nasturtium buds like capers and used them to season food. The artist Claude Monet grew nasturtiums in his garden in Giverny, France, and their descendants grow there today.
These old-fashioned favorites are having a moment as gardeners have rediscovered heirloom plants. Nasturtiums have showy flowers with a sweet fragrance. They may be single or double-blooms, and they come in a slew of colors including orange, yellow, maroon, red, pale yellow and white. You can get seed packs with mixed or single colors.
Nasturtiums are a cool-season annual. That means they're exhausted as soon as temperatures top 85 degrees, so grow them in early spring or fall. In Zones 2 to 8, plant them after the last spring frost for spring and early summer flowers. If you live in a tropical climate where freezes never come, plant them in the fall for winter blooms.
Nasturtiums come in three basic types:
Mounding nasturtium varieties are small and bushy plants, growing 15" tall, 12" wide. They stay where you put them, no trailing or creeping, so they're tidy plants. They're a good choice for beds, borders and small space gardens.
Semi-trailing nasturtium varieties are medium-sized plants with vines that grow 2 to 3 feet long, making them ideal for baskets or pots. They look lovely trailing over the edges of the container.
Climbing nasturtium varieties are large plants that grow vines reaching as tall as 12 feet. They pull themselves up with curling leafstalks. Plant next to a wall or trellis to add height to a garden or make a living screen of flowers. They can also be a groundcover.
Botanical Name: Tropaeolum majus
Common Names: Nasturtium
Bloom Time: Summer, Fall
Hardiness Zones: 9 to 11, grown as an annual in cooler zones
Planting & Caring for Nasturtium
- Mulch the soil to keep weeds down and reduce the amount of watering you have to do.
- Water regularly, about one inch per week. Nasturtium get ratty looking and stop blooming fast if they get too dry.
- Do not fertilize them. This is rule one of nasturtium care. If you overfeed them, they'll put out lots of leaves and not many flowers. You planted them because you wanted flowers, so step away from the Miracle-Gro.
- Clip off faded flowers to keep them blooming.
Harvesting and Using Nasturtium
- Snip off blooms and young nasturtium leaves and sprinkle then on salads.
- Use as an edible garnish in cocktails.
- Save some seeds for next year's garden. Dry them out and store them in a paper envelope in a cool, dark place.
Pests and Problems
Nasturtium attract whitefly and cabbage caterpillars. That's good, and it's why smart gardeners use them as a companion plant in a vegetable garden. The bugs get on the nasturtiums instead of the veggies, and you can catch them on the nasturtium before they destroy your tomatoes. Just spray the nasturtium with a hose to blast the aphids and whitefly, and pick off the cabbage caterpillars by hand.
They repel Japanese beetles, another reason they're a perfect neighbor for your vegetables.
Recommended Nasturtium Varieties
'Alaska' series have variegated leaves speckled in cream, and blooms in gold, orange, salmon and mahogany. They're an heirloom variety that gets 10" to 12" high and 8" to 10" wide.
'Jewel' series has double and semi-double flowers.
'Peach Melba' is a bushy dwarf with semi-double butter-yellow flowers that have orange-red centers.
'Empress of India' is a Victorian heirloom with blue-green leaves and deep red flowers. Plants get about a 1' high and 10" wide and are a good choice for containers, hanging baskets or small kitchen gardens.
'Vesuvius' is an heirloom variety grown in kitchen gardens since the late 1800s. It has salmon blooms and dark, blue-green leaves.
'Whirlybird Mix' has yellow, orange, rose and red blooms.
Semi-Trailing Nasturtium Types
'Gleam' series was first found growing in a convent garden in Mexico in the 1920s and became popular in U.S. gardens during the Depression, with home gardeners selling their seeds to help pay the bills.
'Troika' comes in red and orange varieties. Orange 'Troika' also has white-streaked foliage.
Climbing Nasturtium Types
'Canary Creeper' (T. Peregrinium) is a vine in the nasturtium genus that produces yellow flowers on vines that reach 8' to 12' in length. It's more cold-hardy than other nasturtium, perennial in Zones 7 to 10.
'Moonlight' has pale yellow blooms.
'Out of Africa' series has dark red blooms on olive-green leaves.