Coriander is both a herb and a spice as it is grown for its tasty leaves and pungent seeds. Coriander is a fast-growing annual that is a vital ingredient in many Asian dishes. If you are a fan of this herb, use it to add a zing to even the simplest salad, sandwich or bowl of soup. Time it right and it’s easy to grow. Be careful, it can rapidly bolt to seed if it is stressed by a lack of water.

Coriander is easily grown from seed. For leaf production, look for ‘slow-bolt’ varieties such as Mr Fothergill’s Coriander Calypso and sow small amounts of seed every few weeks. For seed production allow the plant to flower and set seed. Dry seeds can be harvested and stored for use as a spice. Coriander flowers are highly attractive to beneficial insects.

When to plant

Coriander likes consistent warmth to grow at its best. However, if it’s too hot, it will flower, bolt and go to seed quickly. Check with hardware and garden centres for advice on varieties for your local conditions.

1. In sub-tropic and tropic regions grow in the cooler seasons from autumn to late winter. Do not plant in the wet season, as it doesn’t like too much water.
2. In temperate and warm temperate grow in the warm seasons from autumn to spring.
3. In cooler areas grow when spring temperatures are above 15℃.

Location

• Select a bright, sunny location that receives full sun for most, if not all of the day. Not only does sun encourage good growth, it brings out the herb’s aromatic flavour. A little afternoon shade may reduce the plant’s tendency for bolting, especially if grown in summer.
• Coriander has weak stems and leaves so choose a sheltered position away from strong winds.
• If space is limited or soil is not free-draining, it can be grown in containers. Move the container around the garden to catch the sun or give it shade on a hot day.

Soil

Get the soil right to harvest a bumper supply of zingy coriander.

Follow our steps for easy soil preparation.

• Coriander does best in a neutral pH (6.5 to 7.5) soil, however it does not like wet feet, so a free draining soil is essential. If a free drainage soil is not available, plant into pots using a premium (red tick – Australian stand) potting mix such as Seasol Advanced Potting Mix.
• Dig in extra homemade compost and organic matter and/or Seasol Super Compost.
• A soil rich in nutrients helps build strong plants, so add Seasol Plant + Soil Booster (100g per square metre) and a fertiliser such as PowerFeed Controlled Release for Tomatoes & Vegetables.
• Water in well and let the soil rest for a week or two before planting.

Step 1 – Sowing seeds

• Coriander grows best from seed into moist, well-prepared soil or in a pot in a premium potting mix, as it doesn’t like to have it’s roots distributed.
• If you are sowing seeds early, sow into seed trays or punnets, use a good quality seed raising mix such as Seasol Seed Raising & Cutting Potting Mix.
• Coriander has a hard coating so soaking seeds overnight in a solution of Seasol or Seasol GOLD in water will help to soften the seed and improve seed germination rates.
• Plant the seeds to a depth of 6mm about 20cm apart.
• Soil should be moist but not wet, so check the soil moisture daily to ensure the seeds have the right conditions to germinate.

Step 2 – Germination

• Expect germination in 10-12 days (although it may vary depending on the climate and temperature). Watch for the tiny leaves to come through the soil.
• When coriander germinates, each seedling has two leaves. These seedling leaves look like two narrow leaves on either side of the stem.
• Gently thin the tiny seedlings to 15-20cm apart when they are about 5cm high to reduce overcrowding and poor leaf and stem development.
• Water gently and apply Seasol GOLD or Seasol weekly for strong healthy leaf growth.

Step 3 – Baby coriander seedlings

• Keep coriander seedlings moist, but not wet, as they will develop poor stems and leaves. Water more frequently if plants are in hot, dry or exposed conditions or if they are growing in containers.
• Protect emerging seedlings from snails and slugs that like to eat on the juicy, young foliage which can destroy crops. (See ‘Things to watch out for’ below for more advice.)
• Coriander are not gross feeders, so apply a liquid fertiliser such as PowerFeed PRO SERIES for Tomatoes & Vegetables every 2 to 4 weeks.

Step 4 – Transplant coriander seedlings

• Transplant seedlings when they are around 5 to 8cm high and have a few leaves, spacing seedlings 20cm apart to allow for good stem and leaf formation. Take care when transplanting young seedlings not to damage the roots or leaves.
• If transplanting purchased seedlings, plant in the same way as above, following the directions on the plant tag.
• Apply a light layer of organic mulch such as sugar-cane mulch, Lucerne or pea straw to help reduce soil drying and reduce stress.
• Water your newly transplanted seedlings in with Seasol GOLD or Seasol to aid plant establishment and strong healthy growth.

Step 5 – Coriander plant growth

• Keep the area around each plant hand weeded or lightly hoed, as weeds compete for space, moisture and nutrients.
• To keep coriander happy and healthy, the key is regular and steady watering. Remember to keep checking mulch and top up where necessary to keep the soil surface cool.
• To keep a steady supply of coriander throughout the cooler months, plant every couple of weeks in small batches. Try different varieties to see which performs the best and which flavour you like the most.
• Every 6-8 weeks apply PowerFeed Controlled Release for Tomatoes & Vegetables to produce a bumper crop. Mix into the topsoil and water it in after application.

Step 6 – Coriander  harvest – leaf

• Coriander can be harvested for the leaf when there is a lot of foliage and it is approx. 20cm high. At this stage the leaves will be tender and least bitter.
• For the stems which tend to be more pungent than the leaves, cut the stem gently at soil level.
• If you are after the whole plant including the root, gentle remove the whole plant so that the roots are not damaged.
• Wash coriander thoroughly and store in a plastic bag in the crisper section of the refrigerator for up to a week. At the end of the season, coriander can also be frozen and used as a flavour for use in curries, soups or stews.

Step 7 – Coriander  harvest – seed

• Seed heads can be harvested once the plant develops flowers and sets seed. The seed head should be brown in colour
• Place the harvested seed heads in a cool and airy place to allow to dry. Once dried they can be stored in an airtight paper bag or container until they are ready to be used in a recipe or for replanting.
• Dry coriander seeds can be crushed into a powder for your favourite recipe. They can also be sown immediately for a continuous coriander crop, if the weather conditions are ideal.

Things to watch out for

• Bolting When growing coriander for leaf, the main problem is bolting – where plants stop leaf production and instead produce flowers and seeds. Allowing coriander to dry out can lead to bolting. For prevention, water regularly.
• Slugs and snails These pests can destroy young plants. Snails and slugs are active at night. Remove by hand or use an organic method such as a beer trap or wood shavings around plants.
• Aphids These tiny black or green pests cluster under leaves. Squash or hose off. Natural chemical controls such as EarthCare Natural Pyrethrum insect spray can also be used to kill infestations. When spraying the foliage follow the direction on the back of the pack and spray both sides of the foliage. Repeat application may be needed for further control. Remember not to spray when beneficial insects and bees are around.