Growing & Saving Coriander Seed

Many of us love growing coriander for its many health benefits in addition to its fabulous flavour. Did you know that coriander binds to heavy metals like mercury, cadmium, lead and aluminum, making it easier to transport them out of your body? This alone is a great reason to include it in your diet and grow it at home.

Healthy coriander - well mulched

However, one of the problems many of us find with growing coriander is its tendency to bolt to seed quite quickly. How do you avoid this happening? ... and how do you get maximum production from your plants?

Growing Slow to Bolt Coriander

1. Selecting Seed - Start with an organic seed, grown locally or from a seed supplier. You can find a list of Australian organic and heirloom seed suppliers at Saving & Sourcing Open-Pollinated Seeds. Try to buy seed from one in your state and ask if the seeds are grown locally or imported so you know what you are getting. If they are grown locally, they are more likely to acclimatise to your local climate conditions.

2. Water - Coriander loves adequate moisture so it's vital you make sure you keep the water up to it during the growing phase. One sure way to get your plant to bolt to seed early is let it dry out!! The long root also needs space to grow deep in a pot or garden bed so make sure you give it enough room.

Mulch heavily after the seedlings have established - you'll find this will help slow down bolting to seed too quickly.

3. Pruning - Coriander, like most herbs, loves a regular haircut! Regular snipping will ensure you get the maximum harvest and a greater production of leaves. You should get at least 4 harvests from one plant if you prune regularly.

Photo courtesy of Sunset.

4. Nutrients - A liquid fertiliser such as diluted seaweed every couple of weeks will also keep it producing healthy foliage. An organic mineral soil conditioner applied to the soil or potting mix when planting will also ensure your plant is healthy and has sufficient food to grow new leaves.

5. Plant Selection for Seed Saving - Most importantly, when you are growing several coriander plants, observation is the key to noticing which plants start flowering first and those that are last. Being slow-to-bolt to seed is the quality you want to preserve in future generations. Use a plant marker to identify the best plant to save seed from.

Harvesting & Processing Seed

After flowering, you'll notice little green seed heads form like these ones from my garden. During flowering, you'll notice many beneficial pollinating insects like bees and wasps will come visit for a feed on the pretty delicate white flowers. This is why you should interplant coriander with fruiting vegetables so the friendly visiting pollinators will help increase your harvest!

Every white flower forms one seed.

Allow the seeds to dry on the plant before snipping off the stalks and storing in a paper bag until fully dry - if you wait too long, they will drop from the plant and self seed. Otherwise, if you have a long period of wet weather, harvest them when green and store till dry before processing.

Then simply rub the seed heads off the stalks, remove the chaff, label and store. By continually following the process of choosing the slowest to bolt plants each season to save seed from, you will breed plants that have this as a dominant quality and extend your harvest season.

The following diagram is courtesy of Milkwood Permaculture on how to breed slow to bolt coriander and is a good visual of the steps.

Have fun and enjoy growing and saving seed from coriander! 

by Anne Gibson