coriander

How to Grow Coriander

Coriander is a staple ingredient in Middle Eastern, Indian, Chinese, Japanese and Thai dishes where leaves, stalks and seeds are used and it can also be used fresh in salads. It’s an easy to grow leafy herb, that can be sown in pots or directly in the ground. 

Sowing 

Surprisingly, coriander has a long tap root which should not be disturbed. It’s therefore best to sow the seeds either directly into the soil where it’s going to grow, or in multi-cell trays to avoid disturbing the roots when transplanting. You can also sow closely in a tray and harvest them as microgreens for a salad. 

For sowing in your Harvst mini-greenhouse, fill the multi-cell tray or pot with general compost, water it and then scatter the seeds out. Cover with 1cm of compost and press down slightly to make sure that the seeds have good contact with the soil. How closely you space the seeds depends on the size of your cell trays and pots, but you can always thin them out if too many germinate. Water again and keep the soil evenly moist until the seeds germinate because if they dry out, it’s likely they won’t germinate at all. This can be aided with a plastic dome over the tray but it’s not a must! As a general rule, the colder the soil, the less moisture you want – a cold and very wet growing medium often results in rotten seeds!

If you want to sow directly outside, scatter the seeds thinly and cover with 1cm of soil. Later, thin out the seedlings to 20cm apart. It’s best to sow regularly for a constant supply of fresh leaves. Every two weeks if you can! Seeds can be sown until late in the season outside and all year around in your S-Series!

Seeds can be slow to germinate and it can help to crush them slightly before sowing. Normally they should germinate within 7-20 days at 13-20°C. 

Plant care 

Coriander does best in well-drained soil, but you must keep the plants well watered. The soil needs to be damp because if it dries out it can make the plant bolt. Bolting means flowering prematurely, and when this happens the leaves are no longer good to use. 

Coriander grows best in full sun, but can benefit from some shade in the height of summer. Only container grown plants should need to be fed throughout the season. 

Growing options 

You can choose from one of the growing options below or do a combination of 2, 3 or 4! 

  1. Baby Leaves/microgreens: Start harvesting the leaves when they have formed a few true leaves! If you pick one or two leaves off each plant, rather than the whole plant, it should keep on growing for a while and give you a few harvests! 
  2. Grow till maturity in your Sprout: When the seedlings have emerged, thin them to 15-20cm apart. This can be done by cutting the rejects with scissors (eat them in a salad!). The compost will only have enough nutrients for a few weeks so you will have to feed the plants with an organic fertiliser throughout the growing season. 
  3. Plant outside: When the seedlings have developed their true set of leaves (not the first set appearing but the second set) they can be transplanted out into your garden. Space them 20cm apart and be careful not to disturb the roots more than necessary. If you have problems with slugs or it’s very cold, you can keep them in your mini-greenhouse a little longer. A bigger plant can resist a slug attack much better! When transplanting seedlings, ideally plant out early morning or evening and/or on an overcast day. Avoid planting at peak sun times or on windy days as this can cause sun or windburn which can lead to death! 
  4. Container Grown: Coriander grows well outside and inside in a container but try to choose one that is at least 15cm wide and deep. Keep in mind that the compost will only have enough nutrients for a few weeks so you will have to feed the plants with an organic fertiliser throughout the growing season. 

Harvesting 

Harvest coriander stems and leaves as you need them. You can pick leaves or cut a stalk at the base, and flowers can also be eaten in salads. If you want to harvest coriander seeds you should let some plants flower. When the plant is just about to die off and the seeds have appeared, pull the whole plant up and hang it upside down. Place the seed heads in paper bags and after a few weeks shake the seeds into the bag. 

Watch out! 

Coriander is relatively trouble-free but young seedlings may be eaten by slugs and snails. If you have a problem with slugs and snails, protect the plants by keeping them in your S-Series or plant them out when they’re a bit bigger. 

Pro Tip

Let one plant go to seed and harvest enough seeds for cooking and sowing your next batch! If you have a surplus of fresh leaves and stalks, store them in airtight containers or freeze.  Frozen coriander will keep its flavour for cooking.

Nerdy facts

Coriander’s botanical name is Coriandrum sativum  but in America it is not known as Coriander. Instead it is called Cilantro! 

Recommended Varieties

  • ‘Calypso’ is British-bred and is quick to grow and slow to bolt. It can be cut right back to regrow at least three times during the summer! 
  • ‘Leafy Leisure’ is vigorous producing masses of leaves and slow to bolt