Nasturtium
Colourful flowers with a peppery taste
An easy-to-grow, abundantly flowering plant that is also edible, nasturtium brightens up both the garden and summer salads with its bright colours.
Nasturtium – a flower of love
Nasturtium comes in many varieties. It has a fine, compact growth habit and grows to a height of about 30-40 cm. It is ideal in pots, as a border plant and on balconies. The flowers are creamy white, yellow, red and orange. The foliage of nasturtium is also very decorative.
Nasturtium originates from South America and came to Europe in the 16th century. Because of its reputation as an aphrodisiac, it was known as the love flower. According to Carl Linnaeus, chickens that were fed cress would lay extra eggs.
In folk medicine, the plant has been used to treat colds and sore throats. Its high vitamin C content made nasturtium a popular food plant in the 16th and 18th centuries. The pickled flower buds were handy to take along for sailors who needed vitamin supplements to avoid scurvy during long voyages.
Sowing and planting nasturtium
Nasturtium germinates and grows quickly, making it a great plant to grow with children. The large seeds are easy to handle for curious little hands.
When the soil warms up in May, it’s time to sow cress directly outdoors. If you want to get extra early plants, it is also possible to plant indoors from April. Soak the seeds for 24 hours before sowing, so they germinate faster. Place the seeds about 2 cm deep in the soil and keep the seedbed moist. The seeds germinate well at room temperature and can be placed in a cool but bright place once the seedlings have emerged.
The roots are a bit delicate. That’s why it’s a good idea to sow cress one by one in plug trays or small pots. Then they do not need to be replanted but can be put out directly in the country in the spring. Wait until the risk of frost is over, as nasturtium is sensitive to frost. Keep about 20 cm. between the plants. Nasturtium thrives in all situations, but prefers sun.
Along with marigold and cucumber herb, bush cress is one of our favourites to grow alongside vegetables. Growing edible flowers alongside kitchen plants gives a wild feel and a lovely splash of colour to the land. Cress is also a great attractant for bees and other pollinators.
Caring for nasturtium
Nasturtium is a fairly undemanding plant that flowers profusely from June. It should not be given too much nutrients, as this can result in plants with lots of leaves but few flowers.
If the plants are attacked by aphids, a soap spray can work wonders. Mix 0.5-1 dl of green soap in a litre of water and spray daily until the aphids are gone. Strengthening the plants with, for example, nettle water is also a good way to keep nasturtium healthy and resistant.
Nasturtium is very sensitive to frost. In autumn, it is a good idea to cover the plants with non-woven fabric overnight when there is a risk of frost. Then you can enjoy the flowering a little longer.
Eat nasturtium? Yes, please!
Pick flowers regularly to stimulate the plant to produce new flowers. Harvest preferably early in the day, when the flavour is at its best. But feel free to let some plants go to seed in order to harvest the seed pods of nasturtium. These are best when they are small and immature.
All parts of nasturtium are useful in cooking. The colourful petals are incredibly beautiful in salads or as decoration on all kinds of food. The flowers also make great holders for a creamy filling. The stems can be used in a similar way to chives, and the leaves are mixed with oil and spices to make pesto. A classic is to quick-boil nasturtium seed pods and preserve them in the same way as capers.
Nasturtium is not only tasty with its peppery flavour, but also nutritious. It contains plenty of vitamin C and iron, among other things.
Author: Johanna Damm
Fact-checked by Erik Hoekstra
Last updated 2022-10-14