Plant of the Month: Coriander

Plant of the Month: Coriander

Coriander, also known as Cilantro, is a herb that divides people – you either love it, or you dislike it, it seems there is no ‘take it or leave it’!!

For those who think that coriander tastes like soap, apparently it’s a matter of genetics – some people have a variant in their genes that “allows them to strongly perceive the soapy-flavored aldehydes in cilantro leaves”.1 If you are one of these people, you’re not alone; the famous chef, Julia Child, thought the same. For others it is just a matter of taste – perhaps one can acquire it in time!

HISTORICAL INFORMATION

Although it is sometimes referred to as ‘Chinese Parsley, Coriander originated in Italy.2  Because of the spread of the Roman Empire and the trade routes to China, it soon spread throughout the world. It has been known for thousands of years. Seeds were found in a cave in Israel and are believed to be 8,000 years old.3

Coriander, known in Chinese as Xiāngcài, was part of mythology: the seeds were believed “to have the power to grant immortality”.  It was mentioned in A Thousand and One Nights, an Arabian classic, a book written over 1.000 years ago.4

The seeds were brought to Britain by the Romans3 and to the Americas by the Conquistadors.4

The scientific name, Corriandrum sativum,is thought to derive from a Greek word meaning ‘stinky bug’, perhaps referring to the smell of the unripe fruit.5 The species ‘sativum’ simply means ‘cultivated’.

DESCRIPTION OF PLANTS and SEEDS

Coriander is both a herb, grown for its leaves, and a spice, grown for its seeds. The roots, stems and flowers are also edible. It is an umbelliferous plant, belonging to the same family as carrots, parsley, fennel and dill.

Coriander is annual plant, prone to bolt (run to seed) in warm weather. Generally, it is sown in early spring, before the weather gets too warm, and early to mid autumn, before the weather gets too cold. The plant grows to 50 cm tall but is narrow, reaching only about 20cm wide. The plant has bright green, aromatic leaves. The seeds are 3-5mm, almost spherical, and a pale off-white to light-brown colour when dry.

When grown for its leaves, it is often referred to as ‘cilantro’; the seeds are most often referred to as ‘coriander’.

HOW TO GROW CORIANDER

Coriander prefers cooler weather and will bolt (run to seed) if the temperature gets higher than 30°C. It will also bolt if the roots are disturbed, so it is better planted directly where you want it to grow.

Beets are sown in early Spring and as the weather cools in Autumn. Coriander is best sown successionally; that is, sow a few plants, wait a couple of weeks, and sow a few more. Continue this throughout the sowing season. This is particularly necessary if growing for fresh leaves and will lengthen your harvesting time by as much as a4-6 weeks.

Coriander is hard seed and needs to be soaked overnight in warm water before sowing. Be careful not to use hot water, if you can’t put you finger in it and hold it there, the water is too hot!! Body temperature is good. Put a plastic label with the seed details written on it (in pencil, ink will wash off) in the container with the seed, particularly if you are soaking more than one type of coriander seed!! The seeds may float when you first put them in the water but they will sink as they absorb the liquid. After the seed has been soaked, any seed that is still floating is probably not viable but you can give it a try if you like!

Coriander can be grown in a container or in the ground. Sow the seed at a depth of 5-6mm. The seeds should germinate, in ideal conditions, in 7-10 days.

Some moths or butterflies may use your plants as hosts for their larvae to feed on. Check the underside of the leaves if you see any such damage. Slugs and snails seem to leave coriander seedlings alone and go for something a little less aromatic.

Coriander leaves can be picked when the plant is 15-20cm tall. Take only the outside leaves, allow the central leaves to remain untouched or you may kill the plant. Seeds are ready to harvest from 100 days (14 weeks).

CULINARY and MEDICINAL USES

Coriander leaves can be eaten fresh in salads or sandwiches. They can be cooked in soups, sauces and preserves. The leaves can be used, whole or ground, as a spice to flavour a wide variety of dishes, both savoury and sweet. Young roots can be chopped finely and added as garnishes to dips, soups and salads. Older roots are tough and need to be slow cooked over a long period of time so are best in soups and stock. They have a strong, earthy flavour.

In traditional and folk medicine, coriander seeds have been used to treat disorders of the digestive, respiratory, and urinary systems.2 Eating coriander is supposed to reduce flatulence and increase the appetite.3 The seed can be used as a poultice to relieve painful joints and rheumatism.6 I am not a medical practitioner nor am I a herbalist so I recommend that you research  further before using any type of food for medicinal reasons.

OTHER BENEFITS

In flower, coriander attracts bees which is good for all other plants in the garden that need pollination by bees.

Growing coriander is believed to deter potato beetle. The growing plants attract hoverflies which feed on aphids. A tea made from the seeds can be sprayed on plants to deter spider mites.7

SEED HARVEST

If collecting the seed to plant in the next growing season, as much as possible allow the seeds to stay on the plant until the plant dies naturally. In wet weather, you may need to collect the seed in a dry spell. Put the seed and plant parts upside-down into a paper bag and hang to dry in an airy location protected from the rain and, if possible, ambient humidity. The seed is not dry enough if any of the plant remains green and the seed is still attached to the plant. If the seed has fallen off the plant into the bottom of the bag, it is probably dry enough.

Coriander seed grows best if really fresh so, even if you are growing it only for the leaves, it would be advisable to collect some of your own seed to plant in the following growing-season.

SEED AVAILABILITY

Coriander ‘Slowbolt’ seeds are available in the Autumn 2022 Seed Catalogue (prices listed are to current, financial PSW members only)

Until next month
Lynne (PSW Seed Savers Coordinator)

 

REFERENCES

  1. Melissa Petruzzello, Why Does Cilantro Taste Like Soap to Some People?
  2. Manjeshwar Shrinath Baliga et al, Dietary Spices in the Prevention of Rheumatoid Arthritis
  3. Andy Hamilton, Coriander – Corriandrum sativum, Cilantro History and Mythology, growing and container growing
  4. Habeeb Salloum, Fresh Coriander – An Exotic Herb Since Antiquity
  5. Online Etymology Dictionary, coriander (n)
  6. Gourmet Sleuth, Cilantro
  7. Peg Aloi, Best and Worst Companion Plants for Cilantro