Coriander is renowned for being difficult to grow. This reputation comes mostly from its bad habit of quickly rushing to flower and set seed (bolting). Yates Coriander is a ‘slow-bolt’ variety that’s less likely to do this, but even the best of corianders is unreliable when it’s very hot, very cold or when the plants experience sudden changes in their growing conditions.
Probably the easiest way to maintain a good supply of fresh coriander is to plant seeds every few weeks from September right though until the end of autumn. Take a break over winter and begin sowing again in early spring. That way, if your coriander does go to seed, you’ll have more fresh plants on the way.
Check the soil moisture regularly if growing in a pot, especially if growing in a terracotta pot – this dries out faster than other materials. Insert your index finger into the soil to your first knuckle – if it’s moist, don’t water, but if it’s moist, water well. If allowed to dry out, coriander will bolt.