Corm
How to grow crocuses
Crocus vernus, C. chrysanthus, C. tommasinianus
Plant crocus corms in September or October, 7 to 10 cm deep and 5 to 8 cm apart, in full sun and soil that drains freely, for flowers in February and March. The flowers only open in sunshine, so avoid shade. In grass, choose Crocus tommasinianus and leave the leaves uncut until they yellow. The main threat is squirrels and mice digging up newly planted corms.
- Hardiness
- Fully hardy
- Position
- Full sun
- Soil
- Free-draining
- Ideal pH
- 6.0 to 7.0
- Water
- Low
- Feeding
- Light feeder
Sowing and planting crocuses
WhenPlant Sep to Oct; flowers Feb to Mar
Starting off
Plant dry corms Sep to Oct, 8 to 10 cm deep in grass or gravel, using a bulb planter in turf. Lift and separate cormlets in Jun every 4 to 5 years if clumps crowd; C. tommasinianus self-seeds in grass. Seed sown fresh in Jun flowers in 3 to 4 years.
Spacing and planting
Plant 5 to 8 cm apart in groups of 20 or more; set corms 7 to 10 cm deep, three times their height. Fine in a 20 cm pan, packed at 3 cm.
Varieties worth growing
- C. tommasinianus 'Ruby Giant'
- Slim, rich purple flowers from early February. The species that spreads best in grass, and reputed to be the one squirrels trouble least.
- C. chrysanthus 'Cream Beauty'
- Soft cream-yellow with an orange centre, scented, in late February. Small enough for pots, pans and rock gardens.
- C. chrysanthus 'Blue Pearl'
- Pale blue with a bronze-yellow throat; several flowers to a corm, and a good partner for 'Cream Beauty'.
- C. vernus 'Pickwick'
- Large Dutch crocus, white striped with purple, in March. The big-flowered type for bold drifts and for showing up in rougher grass.
- C. speciosus
- Autumn-flowering crocus with violet-blue flowers in October. Plant in August or September as soon as corms arrive.
Crocuses month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
First C. tommasinianus open in mild spells at the end of the month. Remove protective wire once shoots show.
- February
Main flowering of species crocuses. Protect yellow flowers from birds.
- March
Large Dutch crocuses flower. Begin feeding pots as the flowers fade.
- April
Leaves are feeding the corm. Do not mow, tie or cut them. Keep watering and feeding pots.
- May
Mow grass areas once the leaves have yellowed. Stop feeding pots and let them dry.
- June
Lift and divide congested clumps. Plant corms from pots out into the garden.
- July
Nothing to do. Order corms.
- August
Plant autumn-flowering crocuses as soon as they arrive.
- September
Plant spring crocuses in borders, grass and pots.
- October
Finish planting. Autumn crocuses flower. Wire over new plantings where squirrels are a problem.
- November
Late plantings can still go in if the corms are firm.
- December
Nothing to do. Keep pots outside in the cold; they need the chill.
Feeding crocuses
Crocuses need almost nothing. In grass and in ordinary borders, give no feed at all. The only useful feed is a liquid one after flowering for corms in pots and for old border clumps that have gone thin.
Minimal, naturalises in grass and looks after itself.
Feeding plan
Planting, September to October
Nothing
No fertiliser in the hole. On heavy soil, a handful of grit under each group helps more than any feed.
In grass, all year
Nothing
No feed, and keep nitrogen lawn feed off the crocus area until the leaves have died back, or the grass outgrows them.
From the end of flowering until the leaves yellow, pots
3 ml per litre of water once a fortnight, three or four times in all. A 20 cm pan needs about half a litre each time.
March to April, tired border clumps
3 ml per litre (30 ml in a 10 litre can) watered over the clumps after flowering, twice, a fortnight apart, about 5 litres per square metre.
Signs to watch
Leaves but no flowers
Corms planted too shallow or starved after years in a pot
Replant 10 cm deep with a high-potash feed in Mar
Flowers tiny and sparse in grass
Nitrogen lawn feed and early mowing
Stop lawn feed near them and mow after May
Corms soft and brown
Rot from wet
Improve drainage
Pests, diseases and problems
Newly planted corms dug up and eaten, with small holes left in the soil or turf
Grey squirrels, which find fresh plantings by the smell of disturbed soil
Plant at the full 10 cm depth and firm the soil hard. Peg chicken wire flat over the area until the shoots come through in January, or cover pots with mesh. C. tommasinianus is said to be taken less often.
Corms disappear over winter with no sign of digging at the surface
Mice and voles tunnelling to the corms
In pots, cover the compost with a layer of sharp grit and fine mesh. In borders, plant in aquatic baskets or surround groups with grit.
Flowers, especially yellow ones, torn to shreds as they open
Sparrows and other small birds
Stretch black cotton thread between short sticks a few centimetres above the flowers, or grow purple and white varieties, which are attacked less.
Buds stay closed or flowers flop and rot
Shade or dull, wet weather: crocus flowers open only in sun and warmth
Plant where the winter sun reaches, such as under deciduous trees or in open lawn, not on the north side of evergreens or buildings.
Corms are mouldy or have dark, sunken patches when bought or lifted
Storage rots on damaged or damp corms
Buy early in autumn, choose firm corms with an intact tunic, reject soft or mouldy ones and plant within a few days.
Pruning
Pruning and care
No deadheading needed. Leave foliage to die down naturally and delay mowing grass areas until the leaves yellow in late Apr to May. Nothing to lift or stake; fully hardy. Divide congested clumps in Jun every 4 to 5 years and replace pot-grown corms yearly.
Good to knowPlant in autumn; leave to naturalise. Early nectar for bees.
Growing crocuses in pots
Crocuses are easy in pots and pans. Use a shallow pot 20 cm or more across with good drainage, and a mix of two parts peat-free multipurpose compost to one part grit. Set the corms 3 cm apart and 7 to 8 cm deep; they can sit closer and shallower than in the ground because they are only there for a season. Leave the pot outside all winter, raised on feet so it drains, and bring it to a doorstep or table when the buds show. After flowering, feed and water until the leaves yellow, then plant the corms out in the garden in June and start the pot again with new ones in autumn.
Crocuses: common questions
Can I plant crocuses in the lawn?
Yes, crocuses naturalise well in grass that is not too thick and is in sun in late winter. Use a bulb planter or lift a flap of turf, set the corms 8 to 10 cm deep in scattered groups, and choose C. tommasinianus or large Dutch varieties. You must leave that patch unmown until the crocus leaves yellow, about six weeks after flowering.
Do crocuses multiply?
Yes, each corm is replaced every year by a new one plus several small cormlets, so clumps thicken steadily. C. tommasinianus also seeds itself and will spread across a lawn or border over several years. If a clump becomes crowded and flowers less, lift it in June, separate the corms and replant them wider apart.
Why did my crocuses not come up?
Corms that fail completely have usually been eaten by squirrels or mice soon after planting, or have rotted in waterlogged soil. Dig where you planted: if nothing is there, protect the next planting with wire mesh and plant deeper. Leaves without flowers point instead to shade, shallow planting, or foliage that was mown off too early the year before.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.