Which spices can realistically be grown in Britain and similar climates, from coriander seed and saffron to ginger and Sichuan pepper, and which are best left to the tropics.
The short answer¶
Most of the world's great spices — black pepper, cinnamon, nutmeg, cloves, vanilla, cardamom — are tropical trees, vines and orchids that cannot be grown to harvest in a temperate climate without a heated glasshouse, and not always then. But a surprising number of spices can be grown in a British garden: the seed spices of the carrot and cabbage families, saffron from a crocus planted in late summer, horseradish, garlic, hardy sichuan pepper shrubs, and, on a warm windowsill, ginger and turmeric.
The seed spices: easy and rewarding¶
Several of the most-used spices are the seeds of annual or biennial herbs that grow readily in Britain.
| Spice | Plant | Sow | Harvest | Notes |
|---|---|---|---|---|
| Coriander seed | Coriandrum sativum | Apr–Jun, direct | Aug–Sep | Choose varieties sold for seed; leafy ones bolt less |
| Dill seed | Anethum graveolens | Apr–Jun, direct | Aug–Sep | Dislikes transplanting |
| Fennel seed | Foeniculum vulgare | Apr–May | Sep–Oct | Perennial; self-seeds heavily |
| caraway | Carum carvi | Apr–May or late summer | Second summer | Biennial |
| Mustard seed | Brassica juncea, Sinapis alba | Mar–May | Jul–Aug | Harvest before pods split |
| nigella | Nigella sativa | Mar–May, direct | Aug | Not the garden love-in-a-mist, N. damascena |
| Poppy seed | Papaver somniferum | Mar–Apr, direct | Aug | Collect from dry, rattling heads |
| Celery seed | Apium graveolens | Indoors Mar | Second year | Biennial; slow |
| fenugreek | Trigonella foenum-graecum | May, direct | Leaves in weeks; seeds need a long hot summer | Leaves are the easier crop (see fenugreek leaves) |
All of these want sun and well-drained soil. See harvesting herbs for drying and threshing seed heads. Home-grown coriander and fennel seed harvested green are something you will not find in a shop.
Saffron¶
saffron is the dried stigma of the saffron crocus, Crocus sativus. It was grown commercially in England from the Middle Ages — Saffron Walden in Essex takes its name from it — and it can still be grown in a sunny, very well-drained British garden or in pots.
- Plant corms in August or early September, about 10–15 cm deep and 10 cm apart, in full sun and gritty soil.
- Flowers appear in October–November, before or with the leaves.
- Harvest the three red stigmas from each flower on the day it opens, with tweezers, and dry them on paper in a warm room for a day or two.
- Yield is small: each flower gives three stigmas, and it takes on the order of 150 flowers or more to make a single gram of dried saffron. A pot of corms gives a few pinches — enough for a risotto or two and a real sense of why saffron costs what it does.
The saffron crocus is sterile and does not set seed; it multiplies by producing new corms. Lift and divide congested clumps every few years in summer. Do not confuse it with the poisonous autumn crocus or meadow saffron, Colchicum autumnale, which looks similar in flower — see poisonous lookalikes.
Hardy trees and shrubs¶
- sichuan pepper — Several Zanthoxylum species are hardy in Britain and grow into prickly shrubs or small trees. They need a sunny, sheltered spot and some years to fruit; some are male and female on separate plants, so check before buying. Harvest the red husks in autumn.
- juniper — Juniperus communis is a native British conifer. Plants are male or female, and only females bear the berry-like cones, which take two or more years to ripen to blue-black.
- Bay — Grows well in the south and in pots elsewhere; see planning a herb garden.
Roots and bulbs¶
- horseradish — Almost too easy. Plant a piece of root in spring and it will be with you for ever; grow it in a large container or a corner you do not mind losing.
- garlic — Plant cloves from October to December (some varieties in early spring), pointed end up, 2–3 cm below the surface. It needs a cold spell to form good bulbs. Harvest in early to mid summer when the lower leaves yellow. Buy seed garlic from a garden supplier rather than planting supermarket bulbs, which may carry disease or be unsuited to the climate.
- wasabi — Grown commercially in southern England in shaded beds fed by spring water; at home it needs cool, constant moisture, shade and patience of about 18 months or more. Possible, but challenging.
Tropical spices on the windowsill¶
- ginger — In spring, choose a plump, fresh supermarket rhizome with visible buds ("eyes"). Soak it overnight, then plant it shallowly in a wide pot of free-draining compost, buds upwards. Keep it warm (above about 20 °C) and moist, in bright indirect light. Harvest small pieces after four to five months, or the whole plant in autumn when the leaves yellow. It will not survive frost.
- turmeric — Grown the same way as ginger, and just as tender. It is slow, taking eight months or more to form a worthwhile crop of rhizomes.
- lemongrass — Root fresh stems in a glass of water, then pot up.
- galangal — Possible from fresh rhizomes, but it needs more warmth and is slower still.
- Cardamom — Sold as a houseplant for its aromatic leaves; it rarely flowers or fruits indoors.
What is not practical¶
| Spice | Why not |
|---|---|
| black pepper | A tropical climbing vine needing constant warmth and humidity; plants are sometimes grown as curiosities, but crops indoors are small |
| cinnamon, cassia | Tropical trees harvested for bark after several years |
| nutmeg, mace, cloves | Tropical trees; nutmeg trees take years to fruit and are male or female |
| vanilla | An orchid vine that must be hand-pollinated and cured for months |
| allspice | Tropical tree |
These are best enjoyed through a good supplier; see buying spices.
📌 Chillies count too
Chillies and paprika peppers are among the most rewarding "spices" to grow at home. See growing chillies.