How to grow saffron

Often claimed to be the world’s most expensive spice, saffron comes from the flowers of Crocus sativus. It is unknown in the wild but was probably selected thousands of years ago from Crocus cartwrightianus, native to Greece, Lebanon and Jordan.

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<i>Crocus sativus</i>
Crocus sativus

Quick facts

What it is: a spice used to colour and flavour dishes, made from the stigmas of saffron crocus flowers
Timing: plant in late summer, harvest in October (may be later in first year)
Difficulty: easy


Crocus sativus is a true autumn-flowering crocus and must not be confused with the highly poisonous Colchicum, which are sometimes known as autumn crocus and, even more confusingly, as ‘meadow saffron’. Genuine saffron crocus can be obtained from specialist bulb suppliers.

Growing saffron

Despite being expensive to buy, saffron is relatively easy to grow.

Crocus sativus corms are best planted in late summer, though September is not too late. Flowers follow soon after in the autumn.

  • Choose a bright, sunny site with rich but well-drained soil
  • Space corms about 10cm (4in) apart
  • Plant them at least 10-15cm (4-6in) deep
  • Water in well

Flowers will usually appear in October, but are often a little later the first year. The flowers are sterile and do not produce seed.

The plants can reach 30cm (12in) tall over the winter, and then die back in late spring. The original corm is replaced by several cormlets, which may take two or three years to flower.

Harvesting saffron

To harvest saffron, use tweezers to pick the long floppy stigmas (bright red saffron threads) out of the centre of each flower. Avoid the shorter, paler orange, upright stamens, which carry the pollen.

About 150 flowers are needed to produce 1g of dry saffron.

How to dry saffron

After harvesting, saffron need gentle drying. Place the threads on kitchen towel on a baking rack, and leave at room temperature for at least 24 hours. Once completely dry, store saffron in an airtight container away from light.

What is saffron used for?

Saffron can be used to both colour food and to flavour it – it is often used in paella, risottos, curries and fish dishes, as well as sweet recipes such as Cornish saffron buns.

When using saffron, a general rule of thumb is to allow two to three threads per serving. A recipe calling for a ‘pinch’ of saffron usually needs around 20 threads.

Saffron should not be used dry. Instead, prepare the dried saffron for use by placing the threads in a ramekin or porcelain cup with 3 tablespoons of warm water, covering and leaving to infuse overnight.

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