In order to look forward to perfect pops of colour in spring, you need to get organised for planting now.
Delicate and colourful, crocus is one of the first to start flowering in February and March. After the harshness of winter, their yellow, white, and purple petals are just a wonder to behold, and a real sign that winter is passing.
As an early flowerer, it is a crucial source of food for bees who emerge from hibernation to find food, often pretty scarce in the early part of year.
Crocus is a perennial which comes back reliably year after year. It does not need a lot of attention, can be planted in grass, at the edge of borders, or in a pot.
How to Grow Crocus
Plant the corms during October and November for an early spring display. Like many spring flowering bulbs crocus corms need to experience a cold spell of 10-12 weeks, so they need to be planted in autumn.
In general, full sun is best, but some varieties are happy in part shade.
Crocus prefer a gritty, well-drained soil, and will benefit from a light sprinkle of bonemeal when planting.
Naturalising Crocus in Grass
Crocus is happy in thick turf with the sun fully on them, and is easy to plant following these steps:
- Cut the grass before planting in October or November.
- Using a bulb planter, cut out about 20 holes, aiming for a natural spread. Make sure the holes are 8-10cm (3-4in) deep and ensure the bulbs are about 10cm (4in) apart.
- Once you are happy with the pattern, add 1½cm (½in) of the spent compost to the bottom of the holes. On heavy soil, use a compost mixed with 50% grit.
- Then place a few corms on top of the compost or grit, and add another 1.5cm (0.5in) of compost over that.
- After flowering, wait until the foliage has died down in May before cutting the grass.
Growing Crocus in a Pot
Crocus grows well and make a lovely display in pots – they can even be brought indoors for a table centre.
- Plant in pots from October onwards. Plant 8-10cm (3-4in) deep in pots filled with peat-free compost, space them out at just one width of the bulb.
- Leave them in a cold frame, or outside if you do not have one, as they need a cold phase to develop their root systems before the demands of flowering. Check them every couple of weeks to see if they are starting to sprout.
- Once they start to sprout, bring them in somewhere warmer, such as into a greenhouse, if you want to force them on for early flowering. Otherwise leave them outside and they will flower as the weather warms.
- If you do want them flowering indoors as a table centre, you will find they will fully open in the warmth. Once in flower, it is essential to keep them cool or they will go over in 4-5 days. Keeping them cool can triple the flowering time, so put them on the doorstep outside when you do not need them as a table centre.
How to Care for Crocus
Water the corms in well only if the ground is really dry when planting. Crocus planted in the garden or in outdoor pots are unlikely to need any further watering than rainfall.
Keep an eye on any pots undercover and keep the compost moist but not too wet as this may cause the bulbs to rot.
After flowering, feed with a weak tomato fertiliser to help build the bulbs back up for next year.
You do not need to deadhead crocus as the flowers will fade naturally.
Leave all foliage in place until it has completely died back to help feed the bulb to ensure good flowering the following year. If crocus are planted in grass, do not mow it until the foliage has died back in May.
Crocus will bulk up and multiply as they naturalise. Established clumps can be dug up soon after they have finished flowering, divided, and planted in another part of the garden.
Crocus are relatively problem-free, but many gardeners have problems with squirrels who love to locate and dig up freshly planted corms.
To avoid this, cover pots or patches of grass with robust netting or chicken wire, placed over the newly planted corms and held down with a few bricks.
There are many crocus varieties available to suit everyone’s colour scheme. Let’s look at a few we like:
Crocus chrysanthus ‘Blue Pearl’
A soft, pearly blue petal with an orange stigmata.
Crocus sieberi ‘Tricolour’
The inside of this crocus shows three distinct colours: the bold golden yellow base, soft blue petals divided, by broad white bands.
An early crocus, with shining silver outer petals and silvery-blue inner petals.
Crocus tommasinianus ‘Ruby Giant’
A good weather resistant variety, this is an early flowering variety which looks great planted in lawns. The purple flowers stand above the foliage.
This is a striking white variety, heavily striped with purple.
Commonly called cloth of gold, this is an old species dating from the 16th century, with slender, orange-yellow flowers with margins of deep bronze.
Crocus ‘Yellow Giant’
A great bold golden yellow, great for neutralising in lawns.