Coriander – cultivation, planting, care and harvest

In addition to the real coriander, which is very common in Germany, there are numerous other varieties that have their own advantages. The most popular types include:
SANTO: Grows up to 50 cm in height and produces a large amount of tender leaves that develop a strong aroma. The greater the distance between the plants, the higher the harvest yield. The seeds are quite small, however.

Italian coriander
A healthy, vigorous plant that can grow up to 80 cm. Above all, it produces large grains that have a pleasant smell and an intense taste.
CILANTRO: This leaf coriander becomes 60 cm high and produces many leaves. In this plant, seed formation takes place late.

Vietnamese leaf coriander
The plant grows 30 cm to 50 cm in height and flowers pale pink in late summer. Therefore it is also very popular as a container plant. Compared to the real coriander, this is a perennial plant that is, however, not winter hardy. This type of coriander is the only one that can be propagated not only by seeds, but also by cuttings or division.

Cultivation outdoors with a sense of proportion

Coriander prefers a sunny to partially shady location. Since sowing can also tolerate light frost, it can be outdoors as early as mid / late March. This takes place in rows with a distance of 20 cm to 25 cm from one another. As a dark germ, the seeds come 1 to 2 cm deep into the ground and are lightly covered with soil. Hobby gardeners who do not use a precision machine, but rather sow by hand, thin out the young plants after germination to a minimum distance of 20 cm.

With regard to the soil, the coriander plant does not make great demands. It also thrives on sandy to loamy soil. A temperature range between 5 ° and 25 ° Celsius is ideal for successful germination. In the field, the germination period is usually two to three weeks. In addition, the young plants should be well watered, otherwise drought stress arises. This leads to a premature stretching of the plant shoots, also called shoots. With regard to crop rotation, which plays an important role in other aromatic plants, coriander does not have any special requirements. This means that a bed can be used for planting coriander for several years in a row.

Growing in the greenhouse for an earlier harvest

If you want to enjoy the benefits of the coriander plant as early as possible, sow the seeds in the greenhouse. Since these are now available on the market in many different sizes, they have also become an interesting investment for hobby gardeners. The seeds can either be planted as a pot culture, with 25 seeds being planted in a 12 cm pot, or directly in the ground. An earlier harvest is also possible if the cultivation takes place in soil press pots. This method was previously reserved for commercial mass operations. There is now a smaller alternative for the hobby gardener, with the help of which you can easily press your own earth cubes for growing young plants. Commercially available potting soil can be used as the substrate, which is ideally moistened before the pressing process. Now the frame is pressed into the earth with all force so that it is full to the brim. The earth cubes produced in this way are placed in suitable containers or growing trays. With this method, only a single seed of each earth cube is placed in the pre-punched recess and is thinly covered with earth. A moistened prick stick can make this somewhat tricky process noticeably easier. Of course, in this case too, thorough watering must not be forgotten. The roots of the young plants take root very quickly and can be completely planted without having to remove pots, which always involve the risk of breaking apart. With this method, only a single seed of each earth cube is placed in the pre-punched recess and is thinly covered with earth. A moistened prick stick can make this somewhat tricky process noticeably easier. Of course, in this case too, thorough watering must not be forgotten. The roots of the young plants take root very quickly and can be completely planted without having to remove pots, which always involve the risk of breaking apart. With this method, only a single seed of each earth cube is placed in the pre-punched recess and is thinly covered with earth. A moistened prick stick can make this somewhat tricky process noticeably easier. Of course, in this case too, thorough watering must not be forgotten. The roots of the young plants take root very quickly and can be completely planted without having to remove pots, which always involve the risk of breaking apart.

Fertilization and mechanical stimulus for a rich harvest

A moderate dose of compost as fertilizer supports the growth of the coriander plant. In addition, liquid fertilizer has also proven itself with hobby gardeners. It has proven to be particularly effective if the ground is dug up in the field before sowing and a layer of mulch or manure about 5 to 8 cm thick is worked into the soil. The sown seed is then covered with a 1 cm thick layer of soil. If you want the coriander plant to grow particularly compactly, you can do this by lightly covering it with cloth or foil. Experienced hobby gardeners distribute a thin layer of mulch between the young plants so that the annoying weeding is kept within limits.

Careful maintenance is essential

Although the coriander plant is basically very easy to care for and undemanding, there are a few tips to keep in mind so that the planting is a success:

• watering regularly;
• Avoid waterlogging in any case;
• larger plants require less water;
• daily weeding;
• Liquid fertilizer or compost promotes growth;
• also work some algae lime into the soil;
• remove weak seedlings;
• observe the minimum distance between the plants of 20 cm.

The choice of the location is a bit tricky, because too much moisture is just as unfavorable as too much dryness. Therefore, the ideal place offers sunshine in the morning and shade in the afternoon. If the coriander plants are grown in the greenhouse, appropriate sun protection on the glass roof should provide some shade in the afternoon.

The right time to harvest

It takes an average of 24 weeks from sowing to harvest. This means that harvesting takes place between July and the beginning of August. If the leaves of the coriander plant are harvested from above, this prevents new flowers from forming and therefore prevents the plant from sprouting. Since not only the leaves, but also the grains of the coriander plant are in demand, the seed heads are harvested shortly before they are fully ripe. The best time to harvest is early in the morning. The rest of the day the seed heads are dried on paper and the seeds detach themselves from the cones. Then they can mature in peace in a dry cotton bag.

Diseases and pests

The most common disease observed in coriander is umbel wilt, also known as umbel brandy. It is caused by a fungus that causes the leaves to wither. Particularly in damp weather there is a risk of cone wilt, against which there is no effective remedy. Infested plants are best removed completely so that they do not infect the entire stand. In the next year, another bed should be chosen for planting coriander.

There are also non-chemical remedies for another disease that can affect coriander. Powdery mildew is known to most hobby gardeners in many ways. A milky white coating forms on the leaves and shoots, especially in muggy weather. Even a light wind causes the transmission to other plants. A large distance between the plants helps prevent powdery mildew. In addition, the coriander plants should not be in close proximity to a compost heap. It is also advisable not to water the plants in the evening so that they are dry before night. If powdery mildew has struck anyway, immediate action is essential. The following is required for this:

• 3 sachets of baking powder
• 50 ml of cooking oil
• some washing-up liquid
• 5 liters of water
• a vat to mix
• a sprayer

The detergent ensures that all ingredients combine well. The infested coriander plants are then best sprayed carefully with this mixture in the evening, and this process should be repeated again after about 10 days.

Is powdery mildew on coriander poisonous?

Basically, powdery mildew is a fungal disease that can affect not only numerous flowers, but also vegetable and aromatic plants such as coriander. It is good to know that powdery mildew is not poisonous in the toxic sense. Nevertheless, it is advisable to wear gloves and possibly a face mask when fighting it. These protective measures should be observed in particular by people with susceptible health and allergy sufferers. Since powdery mildew can also cause a rash, it is advisable that your legs and arms are covered with clothing. Since coriander is usually only consumed in very small quantities as a spice, there are no health risks to be feared if there are infected leaves or grains underneath. In any case, all components of the coriander plant must be thoroughly cleaned with water before use. Incidentally, plants infected with powdery mildew should not be disposed of on the compost, as otherwise the spores could spread further in the garden. The best prevention against powdery mildew infestation are strong and resilient plants that are fertilized regularly.

Make your own liquid fertilizer for coriander

Basically, no garden should be without a compost heap. But this is not always possible, so that liquid fertilizers have to be used to strengthen the plants. If you are hoping for a rich coriander yield, you can easily make liquid fertilizer yourself. The following ingredients are required for this:

• Cooking water from potatoes
• Coffee grounds residue
• crushed eggshells
• Nettle
• dandelion
• Onion skins

All ingredients are mixed well and stirred every now and then in a wooden tub for two weeks. The manure produced in this way is ideal as a liquid fertilizer, not only for coriander plants. Due to its somewhat pungent smell, manure manure should not be made on the balcony or terrace.

Conclusion
For more than 5000 years, coriander has been known all over the world as a medicinal and aromatic plant. Coriander seeds have even been found in tombs of Ancient Egypt. To this day, the plant has lost none of its popularity. In addition to commercial cultivation, there are coriander plants in numerous hobby gardens, the leaves and seeds of which are not only used in private households for the preparation of food and bread. They do not require extensive maintenance and are also quite resistant and robust. In addition, their bright flowers contribute to the visual beautification of the garden.