Crocuses: when to plant the corms, crocuses in a lawn and how not to confuse them with meadow saffron

When and how deep to plant spring and autumn crocuses, how to create a crocus carpet in a lawn and how to tell a crocus safely from the highly poisonous meadow saffron.

In brief: Plant spring crocuses in September and October 8–10 cm deep, in a lawn large-flowered ones up to 12 cm, 5–9 cm apart. Autumn crocuses go into the ground at the end of August and in September. Beware of confusion with the highly poisonous meadow saffron, which flowers in autumn and has 6 stamens, whereas a crocus has only 3.

Botanically	crocus (Crocus), Iridaceae; a corm is planted, not a bulb
Planting spring-flowering	September–October, in a warm autumn also the beginning of November
Planting autumn-flowering	end of August – September
Depth and spacing	8–10 cm (in a lawn up to 12 cm), 5–9 cm apart
Flowering	spring-flowering February–April, autumn-flowering September–November
Toxicity	crocus mildly (digestive upset), meadow saffron highly

Crocuses are the cheapest way to have a colourful lawn in February and March. One corm costs a few pence, goes into the ground in a few seconds and in good conditions multiplies by itself for decades. Botanically they are Crocus, and "crocus" is simply the garden name for the same genus.

Because it is now the end of September, you are probably dealing with two things: when and how deep to plant the corms, and whether the purple flower that is flowering in your lawn right now is a crocus. Both are below, and we start with the more important one.

Crocus, saffron crocus or meadow saffron?

In September and October purple goblets flower in meadows and gardens, popularly called "autumn crocus". Often, however, it is meadow saffron, a plant from a different family which contains colchicine and is among the most poisonous plants of our countryside. You can tell them apart by the flower and by the leaves:

Feature	Spring crocus	Autumn crocus (e.g. saffron crocus)	Meadow saffron
flowers	February–April	September–November	August–October
stamens in the flower	3	3	6
leaves	narrow, with a pale stripe in the middle, together with the flowers	narrow, with a stripe, with the flowers or after them	broad, glossy, only in spring, without flowers
underground organ	small corm in a netted tunic	small corm	large corm in a brown tunic
toxicity	mild, digestive upset	mild	highly poisonous

The simplest way is to count the stamens: three means crocus, six means meadow saffron. Beware of meadow saffron in spring too. Its broad leaves grow in damp meadows and floodplain woods, and every year there are cases of poisoning where someone mistook them for wild garlic. Meadow saffron is also sold in garden centres as an ornamental bulb (Colchicum), so when buying autumn "crocuses" read the Latin name.

When and how to plant the corms

Spring crocuses are planted from September to the end of October. In a warm autumn, when the soil is not yet frozen, you can also plant at the beginning of November, but corms planted late flower somewhat later and more weakly. Autumn species need to go into the ground earlier, at the end of August or in September, otherwise in the first year they flower only in November or not at all. Where to fit crocuses into the overall autumn planting plan can be found in the article autumn planting of bulbs.

When buying, choose firm corms without mould and soft spots. Large Dutch hybrids (Crocus vernus) have large corms and flower in March. Species crocuses such as Crocus tommasinianus or Crocus chrysanthus have small corms, flower 2–3 weeks earlier and naturalise more readily in a lawn.

In a bed plant the corms 8–10 cm deep and 5–9 cm apart, tip upwards. On light sandy soil rather deeper, on heavy soil shallower. Corms planted shallowly are pushed out by frost and easily found by mice.

A crocus carpet in a lawn

In a lawn crocuses look best in irregular groups, as if they had grown there by themselves. Plant large-flowered hybrids in a lawn deeper, about 12 cm, and 9 cm apart.

Make the last mowing before planting short; it is easier to work in short grass.
Scatter a handful of corms loosely over the area and plant them where they land.
Use a planting trowel or bulb planter to make a hole to the right depth and put the corm in tip upwards.
Fill the hole with soil, press the turf down and water.
For a larger area cut the turf with a spade in an H shape, fold back both halves, put 10–20 corms into the exposed soil and return the turf.
In spring do not mow the area with crocuses until the leaves turn yellow, usually 6 weeks after flowering.

Delaying the first mowing is the only condition for crocuses to persist in a lawn. If you mow the leaves green, the corms do not replenish their reserves and disappear within a few years. How to combine spring lawn care with bulbs is described in the spring lawn crash course.

Crocuses in a bowl and on a windowsill

In a container crocuses are the top layer of layered planting, planted 7–12 cm deep above tulips or daffodils. Plant crocuses on their own densely, corm next to corm, in a free-draining substrate. Put a drainage layer at the bottom of the bowl; the principles are described in the article drainage in a flower pot.

You can also force crocuses on a windowsill. Keep bowls planted at the beginning of October for 12–15 weeks in the cold, below 9 °C, and in the dark, for example buried outdoors in the ground or in a cool shed. Then move them into a room at 10–20 °C. They begin to flower roughly in February. After flowering let them ripen and plant them in the garden in autumn.

Mice, voles and birds

Crocus corms are a delicacy for mice and voles. If after winter you are left with only holes in the lawn, next time plant in bulb baskets or put a piece of wire mesh with a mesh size of around 1 cm under the hole. A layer of coarse gravel around the corms also helps. The difference between pests and useful underground animals is explained in the article mole and water vole.

In spring blackbirds and sparrows sometimes tear off flowers, most often yellow ones. This does not harm the corms; you just lose part of the flowering. A net over the bed for a few weeks or a choice of purple and white varieties helps.

Crocuses in the Czech countryside and saffron as a spice

Two crocuses grow wild in the Czech Republic and both are, under Annex II of Decree 395/1992 Coll., highly endangered: the spring crocus (Crocus albiflorus) and the Carpathian crocus (Crocus heuffelianus). Do not pick or dig them up in the wild. Only corms from a nursery belong in the garden.

The spice saffron comes from the autumn saffron crocus (Crocus sativus). It consists of the dried red stigmas, three from each flower. In the garden you can try it in free-draining soil in a warm spot; the corms are planted at the end of August. Because of the risk of confusion with meadow saffron, harvest stigmas only from plants that you demonstrably planted yourself as Crocus sativus.

Are crocuses poisonous?

Spring crocuses are only mildly poisonous. If a dog or cat chews them, vomiting, diarrhoea and drooling may appear. Meadow saffron is much more dangerous; even a small amount causes bloody vomiting, diarrhoea and organ damage. If an animal has been chewing an autumn "crocus" and you are not sure what it was, act as if it were meadow saffron and call a vet at once. For a child call the Toxicological Information Centre on 224 919 293 or 224 915 402.

Frequently asked questions

When should I plant crocuses?

Spring crocuses from September to the end of October, in a warm autumn still at the beginning of November. Autumn species at the end of August and in September. The earlier you plant the corms, the earlier they root.

How deep are crocuses planted?

In a bed 8–10 cm, large-flowered hybrids in a lawn about 12 cm. Spacing 5–9 cm; in a container, corm next to corm is fine.

Why do my crocuses not flower?

Most often the leaves were mown green last year, the corms were eaten by mice, or the crocuses are in shade under evergreen shrubs. Delaying mowing, baskets against rodents and a sunnier spot help.

Do crocuses have to be dug up after flowering?

No. In a bed and in a lawn they stay in the ground and multiply by themselves. They are dug up only from temporary spring containers, and only after the leaves have turned yellow.

How do I tell a crocus from meadow saffron?

A crocus has 3 stamens in the flower and narrow leaves with a pale stripe. Meadow saffron has 6 stamens, flowers in autumn without leaves and its broad leaves grow only in spring.

Sources

Updated: 27 September 2026

Author: Jana Vránová, the editorial name of the Pěstík.cz team. She writes about the garden, herbs and essential oils. We take safety and dosage information from specialist literature and official sources, which we cite in every article.