The Chilean blue crocus, a real eyeful - and it's not a crocus!
The native habitat of Tecophilaea cyanocrocus is the high Andes, where it grows on dry stony slopes from around 2000 to 3000 m altitude. In the wild it flowers in the Southern Hemisphere in spring, from October to November, and here in the UK from February into March. It immediately catches your eye in the Davies Alpine House with its amazing, deep blue flowers.
Tecophilaea cyanocrocus in the Davies Alpine House
With its crocus-like flowers it soon became known as the Chilean blue crocus although this plant is not actually a crocus but in a completely different family, Tecophilaeaceae. As well as the true species, two cultivars are also grown at Kew: Tecophilaea cyanocrocus 'Violacea' has flowers of a slightly more purple hue and T. cyanocrocus 'Leichtlinii' has more white in its petals.
Left, T. cyancocrocus 'Violacea', and right, T. cyanocrocus 'Leichtlinii'
We grow this eye-catching plant in pots in the Alpine Nursery but there are also some growing outside on the Rock Garden. Early each spring pots from the nursery are displayed in the Davies Alpine House.
Cultivation is quite straightforward. We use a free-draining compost and re-pot the corms each year in August. After re-potting, we plunge the pots in a sand bed, and water both the pots and the sand. The sand is kept damp until the corms come into growth, when we water them freely. Watering is eased off as the plants die back for their summer rest. During this resting period, the pots are sprayed over about once a fortnight, as they don't like to be dried out completely.
We keep the pots in a glasshouse to protect them from hard frosts but they will often survive outside in milder parts of the country, as long as they don't get too wet in the summer.
Pots of Tecophilaea cyanocrocus in the sand plunge in the Alpine Nursery
Propagation is mostly by corm offsets, though occasionally we will sow seed in spring. Seedlings are left undisturbed in the seed pots for about three years. This means that when we come to separate them and put them into bigger pots, they have already formed a small corm, which is less likely to suffer damage during repotting. After about five years they should flower and dazzle you with their electrifying blooms.
- Sue -