Flowering time (month)
Ornamental or utility value
The great nasturtium (Tropaeolum majus) originates in Central and South America, where it has always been one of the traditional medicinal plants in Brazil, Chile, Peru and Bolivia. It is the best-known member of the nasturtium family (Tropaeolaceae). Today’s garden form is a hybrid, but its original forms can no longer be traced back. Sometimes the nasturtium (Tropaeolum) is confused with its relative, the watercress (Nasturtium). This is because the nasturtium is called “nasturtium” in English. The great nasturtium is the “medicinal plant of the year 2013”.
With us, the fast-growing Kapuzinerkresse is cultivated annual, in its South American homeland, it is perennial. If you give it a climbing aid to the side, it climbs upwards, otherwise it grows crawling and is also suitable as a ground cover. Their tendrils can be up to three metres long in one season. The thin, round stems have leaves and flowers about 20 centimetres in height.
The whole-edged, shield-shaped leaves of nasturtium have a water-repellent lotus effect. Each leaf has nine leaf veins which radiate from the centre. The leaves are light to dark green, smell and taste spicy-hot and remind of cress or mustard. They contain healthy mustard oils, which help against colds, viruses, bacteria and fungi. The leaves of nasturtium can be used raw as a seasoning herb in quark, herb butter or in salads. The older and darker the leaf, the sharper the aroma.
The conspicuous, large flowers give the nasturtium its name. Their pointed appearance used to be compared to the hoods of the monks. The bright yellow, red or orange flowers (plain or patterned) appear between July and October. The decorative single flowers appear on the long tendrils. The corolla has five sepals and tapers at the opposite end into a slightly curved, about three centimeter long spur. The flowers of the nasturtium also have a mustard-like aroma, but are somewhat milder, but also have an antibiotic effect. They are a popular salad decoration. The flowers like to hide earwigs, which should be shaken out carefully when picking the flowers. The large flowers are pollinated by insects.
After flowering, nasturtium forms three solitary cleavage fruits from three pistils each. The young buds are edible and can be eaten like capers in vinegar, salt and oil. The ripe seeds can be dried and ground and used as seasoning powder.
Location and soil
The sun-loving nasturtium is a classic summer bloomer. She prefers a sheltered, sunny place in the bed and also grows in the balcony box. The more light the great nasturtium gets, the greater is its abundance of flowers. It thrives just as well in semi-shade or even in shade, but here you have to be content with many leaves and few flowers. Despite the flowering splendour that nasturtium produces in summer, it only needs a moderately humus soil, not too rich in nutrients, often with a clay or sand content. In a soil rich in nutrients, it also tends to form more leaves than flowers.
Because nasturtium is annual in our latitudes, it must be sown anew every year. The sowing of the large round seeds of the great nasturtium takes place from February to April in growing pots. Allow the seeds to soak in water for a few hours before application. Then place two seeds per pot two to three centimetres deep into the growing soil. Germination takes about two to three weeks at room temperature. After the last frosts, the young plants may be planted into the bed. Preferred specimens have the advantage that they start flowering earlier. The good germination capacity and the rapid growth of the dark germ allows direct sowing into the bed or tub from May onwards. The nasturtium usually sows itself in the flower bed and reappears every year.
Planting and care
The great nasturtium belongs to the typical easy-care farm garden plants that prefer to grow undisturbed. Once used, it rises independently to trellises, fences or screen walls and reaches an impressive size. Fertilization is sparse and with a low nitrogen content, as otherwise leaf formation is stimulated, which is at the expense of the flowers. You should also cut off seeds regularly – if no seeds are needed for the next year – as this prolongs the flowering period. The nasturtium evaporates a lot of water due to its lush foliage. The sunnier the location, the more water the plant needs. In summer it may be necessary to water plants in the morning and evening, especially plants in tubs or flower boxes. It tolerates tap water without any problems. Do not pour over the flowers, but always close to the ground. Too long or disturbing tendrils can simply be cut. Tropaeolum majus is an annual summer bloomer and not winter-hardy.
Use in the garden
With its long, densely foliated tendrils, the Great Nasturtium is the perfect screen greening. It grows reliably and quickly along every climbing aid – upwards as well as in width. A flower pot or box is also sufficient – which is why it is very popular with balcony gardeners. It is also suitable for decorating garden fences or pergolas. Their hanging, luxuriantly flowering tendrils also cut a fine figure in hanging baskets. The great nasturtium is not only a beautiful ornament, but also a popular medicinal and aromatic plant. It is also often planted in vegetable beds and is a good neighbour for cabbages. Harvest only the young leaves and flowers for consumption, because stems and old leaves are woody and not so tasty. Tip: Plant a nasturtium on the corner of a raised bed and let the tendrils hang decoratively. If you have plenty of space in the bed, you can also use nasturtium as a ground cover. However, most varieties cling to anything that gets in their way.
In addition to the classic garden varieties, which flower yellow, orange or red, there are now interesting varieties with double flowers or alternative flower colours. Thus ‘Purple Emperor’ displays red-violet flowers. In the semi-double varieties, ‘Scarlet Shine’ shows bright red and ‘Double Delight Cream’ pastel yellow flowers. Diamond of the Occident’ produces a colourful blend of white, pink, orange and yellow flowers.
Diseases and pests
The large Kapuzinerkresse defends itself successfully with its mustard-oils against some pests and mushrooms. Nevertheless, it is very popular with aphids. That is why rose gardeners like to plant nasturtium near roses as aphid food to protect them. Tip: If the plants are only sown in summer, the aphid infestation is usually lower. Also the big Kohlweißling deposits its eggs gladly at the Kapuzinerkresse. Food traces clearly indicate the caterpillar infestation.
In an interview with our store editor Dieke van Dieken, plant doctor René Wadas reveals his tips against aphids.Credits: Production: Folkert Siemens; Camera and Editing: Fabian Primsch
Nasturtium in the our store-Shop
I am Don Burke, one of the authors at My Garden Guide. I am a horticulturist that cultivates, grows, and cares for plants, ranging from shrubs and fruits to flowers. I do it in my own garden and in my nursery. I show you how to take care of your garden and how to perform garden landscaping in an easy way, step by step.I am originally from Sydney and I wrote in local magazines. Later on, I have decided, more than two decades ago, to create my own blog. My area of specialization is related to orchid care, succulent care, and the study of the substrate and the soil. Therefore, you will see many articles dedicated to these disciplines. I also provide advice about how to improve the landscape design of your garden.