Cornflower: Sowing, Location & Use

The cornflower not only provides food for many insects, but is also often used in the kitchen. Their valuable ingredients can help against a wide variety of ailments.

The cornflower (Cyanus segetum) usually inspires with its bright blue flowers, but can also bloom in other colors. We present the most beautiful varieties and give helpful tips on sowing, care and use.

Cornflower: flowering period, origin and properties

The blue flowers of the cornflower are known to most. They are often found together with the corn poppy in parks or in flower strips next to grain fields. Since they used to like to grow in the middle of the field, the name of the cornflower is probably not far-fetched. The cornflower blooms from May to September and you can enjoy its showy but odorless flowers. These are often visited by bees and insects. The plant, also known as cyanide, is now rarely found growing wild in the field. But are cornflowers therefore protected? No, cornflowers are on the early warning list of the Red List, but they are not yet protected by law.

The annual, herbaceous plant originally comes from the Mediterranean region and has spread to Central, Eastern and Western Europe with the help of humans. It belongs to the daisy family (Asteraceae), formerly belonged to the genus der knapweed (Centaurea), but now forms the genus of blue knapweed (cyanus). The cornflower grows upright and has various shaped leaves covered with downy hairs. Upper cornflower leaves are usually entire and lanceolate, while lower leaves are serrated and divided. Cornflowers can grow up to 90cm tall and come in a variety of varieties for the garden. Since the cornflower contains ingredients such as flavonoids, tannins and bitter substances, it was used as a medicinal plant in the past. Today it is sometimes still used in the kitchen, where the flowers in particular are used to decorate dishes.

Are cornflowers perennial? No, cornflowers are annual plants, so they will not sprout again the next year. However, by self-sowing, the cornflowers multiply in suitable locations and new plants are created.

Confusion of cornflowers: The various representatives of knapweed (Centaurea) look relatively similar to the cornflower. However, knapweeds have broader, mostly incised leaves. Also the common chicory (Cichorium intybus) looks a little like the cornflower. On closer inspection, however, it can be recognized by the differently shaped small flowers.

The most beautiful varieties

There are some garden varieties of the cornflower that impress with their differently colored flowers. We present a few here:

• Cyanus segetum ‘Blue Ball’: This variety comes in the classic cornflower blue and has double flowers that appear even more lush. It can reach heights of 80 cm. Unfortunately, double varieties like ‘Blue Ball’ are less bee-friendly.

• Cyanus segetum ‘Classic Romantic’: You can get several colors in one flower with the 'Classic Romantic' variety. The flowers are patterned pink and white, sometimes with a higher proportion of white, sometimes with more pink in the flower. The growth height is 60 - 90 cm.

• Cyanus segetum ‘Red Lola’: A cornflower in pink is the 'Rote Lola' variety, which can grow up to 80 cm tall.

• Cyanus segetum ‘Black Ball’: The dark red-violet of the 'Black Ball' cornflower appears almost black. At around 60 cm, it remains slightly smaller than most other varieties.

• Cyanus segetum 'Blue Boy': The cornflower 'Blauer Junge' blooms in a strong blue and has full flowers. It grows 50-70 cm high.

Sow and plant cornflowers

Cornflowers are a real eye-catcher in the garden and are also easy to care for. The easiest way to establish cornflowers is to sow them.

The right location for cornflowers

A suitable location for the cornflower is sunny and not too nutrient-rich. The soil should be loose, permeable, and preferably slightly calcareous. The cornflower can also cope with sandy soils.

Cornflowers in mixed culture: Visually and also in terms of location requirements, they fit poppy (Papaver rhoeas) or daisies (Leucanthemum) excellent with the cornflower. Since the cornflower is a magnet for beneficial insects, it is often part of Seed mixtures for flower meadows.

Instructions for sowing cornflowers

Since the cornflower is not a perennial, it must be sown again every year unless it self-seeds. Sowing cornflowers is very easy:

• Sow seeds between March and April
• If sowing occurs later, the plants will remain smaller
• Sow in small clusters of about 3-10 plants
• Maintain a planting distance of about 30 cm
• Only cover the seeds lightly with soil, as the cornflower needs light to germinate
• Germination after about 14 days

Cornflowers in the pot: Cornflowers can be kept in pots, for example in balcony boxes, without any problems. Since the cornflower develops quite deep roots, the pot should be at least 30 cm high. In addition, a drainage layer is absolutely necessary so that the water can run off well. You can make these out of potsherds, expanded clay or pebbles. It is best to use high-quality potting soil mixed with a third of sand as a substrate. As a basis, for example, ours is suitable Plantura organic potting soil, which has a high humus content and can store water well. In addition, it does not require peat and, thanks to its natural ingredients, does not pose a problem for pets and garden animals. The expanded clay content in our soil also benefits the cornflower, as it increases permeability. You are welcome to mix in more expanded clay, then the cornflower will feel all the more comfortable.

The right care

Since the cornflower is an easy-care plant, there is actually not much left to do after successful germination in suitable locations.

The cornflower usually copes very well with conditions that are quite poor in nutrients and does not require any additional fertilizer. Only in special cases, i.e. on very poor locations or in tubs, if the cornflower grows in very old or reused potting soil, does fertilization make sense shortly before flowering. In this case, use a complete fertilizer that provides all the nutrients, such as ours Plantura organic universal fertilizer. Our fertilizer not only supports your plants, but also soil life. A weak dosage is sufficient for the cornflower. Incidentally, over-fertilization is indicated by a lack of flowering or by limp leaves. In addition to spider mites and aphids, over-fertilization is the most common cause of sick cornflowers.

Tip: In representatives of the daisy family, the flower head consists of many small individual flowers, which, however, are often mistaken for simple petals. The outer flower ring is sterile, only the central tubular flowers are fertile.

You only have to water the cornflower during longer dry periods or in midsummer. Avoid waterlogging, especially with plants in pots, and make sure that the water can drain off easily.

A pruning is not necessary, but you can get the cornflower to bloom again by removing the dried inflorescences.

Are cornflowers hardy? Cornflowers are not hardy, but annual plants that do not sprout again the following year.

Propagating cornflowers

The best way to propagate cornflowers is by sowing, for which you can also collect the seeds from the flowers yourself. After flowering and successful fertilization, the pappus that is typical of daisy family forms. This one looks hairy-furry and sits on top of the fruit. The cornflower seeds can be harvested from this point in time and should be stored dry until sowing next spring.

Are cornflowers edible?

The blossoms of the cornflower are edible and look very decorative on dishes and in salads. The entire flower should not be used. It is better to pluck out the individual small flowers. In contrast to the flowers, the calyx and the leaves do not taste spicy, but rather bitter. The cornflower is therefore not poisonous, because it was even used for healing in the past.

Effect and use of the cornflower

The cornflower is of no particular importance in medicine today. However, since it contains some medicinally effective ingredients such as mucilage and bitter substances, It used to be used to treat digestive problems, insect bites and chronic coughs, among other things deployed. For example, the dried seeds were used for this. A blue flower tincture made from cornflower blossoms and many other blue-flowering herbs is also said to help against restlessness. For a cornflower tea, you can dry the blossoms of the cornflower or use them fresh.

Also part of the blue flower tincture is the borage. With us you will learn everything about planting, care and harvesting.