Sun and Soil Requirements:
Grow in full to partial sun and in a friable, well-drained soil.
The light requirement isn't as difficult to meet in this case as it is for many sun-lovers, since crocus flowers bloom in spring, meaning they can be grown under deciduous trees. Crocus flowers get enough sun in the spring (before the trees leaf out) to grow and acquire the nutrients they need for the growing season. But don't grow them under evergreen trees, since the latter cast shade during the entire year and would deprive your crocus plants of the necessary springtime sunlight.
Types of Crocus Bulbs:
The name derives from the Greek for "saffron." Indeed, saffron is harvested from the stigmas of one particular type of crocus: C. sativus. C. sativus, like Colchicum autumnale (different genus but bearing a striking resemblance) and similar plants, is one of the fall-blooming crocuses. It is planted in spring or summer, unlike the spring-blooming types (which are planted in fall).
Spring-blooming types include:
- C. vernus
- C. chrysanthus
- C. tommasinianus
- C. sieberi
Problem is, if you buy them from a home improvement chain store in the U.S., you won't necessarily know exactly what it is you're planting, as the scientific plant name may not be included.
When to Plant Crocus Bulbs:
How to Plant Crocus Bulbs:
Plant 2 inches deep and provide 2-3 inches of spacing. The pointy part should face up. Some fertilize at planting time with bone meal. Others say bone meal is unnecessary at this time and invites pests to dig around, which could dislodge your crocus bulbs. If this is a concern, lay chicken wire on top of the ground after planting. Or you could hold off on the bone meal till spring and just use some compost when planting.
Divide to prevent overcrowding and/or to propagate.
For the sake of plant nutrition, leave the foliage alone after blooming until it fully yellows. If you're growing your plants in a planting bed, it's easy to leave them alone for this time period. But if you're growing crocus flowers in the lawn, it may be difficult to remember that you won't be able to mow until the foliage yellows (about 6 weeks after bloom). That's because the leaves are so grass-like that they blend in to lawns. To help yourself remember not to mow in that area, stick stakes in the ground as the blooms of your plants start to fade, to mark the "no-mow zone."
Crocus Bulbs: Uses, Squirrel Control:
Squirrel pests like to dig up crocus bulbs. Spreading blood meal around the planting bed will help deter the pests (and green up the grass considerably, if you're planting crocus bulbs in a lawn area), but a surer squirrel-control method is to lay chicken wire on top of the ground where you have just planted your crocus bulbs. The nice thing about protecting crocus bulbs in this way is that, since crocus plants are relatively small, there's no need to remove the chicken wire later, unless it's an area you'll need to mow (for bulb plants that grow bigger, you'd have to remove the chicken wire before they push up in spring, lest the foliage be cut on the sharp wire).
Rabbits present a challenge in growing crocus, too, because this spring bulb is one of the plants that rabbits eat. These pests will treat the above-ground growth as if it were part of a salad bar. For quick rabbit control, you can apply BirdBlock over your plants, but this netting spoils the overall effect. I recommend planning ahead, instead, and setting up a rabbit-proof fence.