While Scotland’s climate can be challenging for some plants, crocosmia is one of those hardy stalwarts that can thrive in a variety of conditions. Its pleated, sword-shaped leaves can grow to almost a metre in height, and the brazen reds, oranges, and yellows of the flowers burst into colour in the late summer garden.

Crocosmia ‘Lucifer’ is probably one of the best known varieties with its fiery red flowers, but other varieties like C. ‘George Davidson’ boast pale, yellow flowers flushed with orange, while the blooms of ‘C. Emily McKenzie’ are bright orange with a tinge of purply-red at the base.

Crocosmia plants are generally low-maintenance, will grow well in a pot on the patio or in the ground, and the flowers last for ages when cut for indoors. Add to that the fact that its vibrant, showstopper blooms are loved by pollinators, especially bees and butterflies, and you have a low maintenance garden winner!

Climate and Sunlight

Crocosmia can tolerate a range of conditions but prefers to be planted in full sun to partial or dappled shade.

Soil Requirements

Crocosmia prefers well-draining soil that is rich in organic matter. Prior to planting, it is beneficial to add some organic matter like compost to improve its fertility and drainage of the soil.

Planting

Crocosmia bulbs, also called corms, should be planted in the spring after the last frost has passed. Dig a hole about 4-6 inches (10-15 cm) deep and place the corms with their pointed ends facing upwards. Space the corms about 6-8 inches (15-20 cm) apart.

A corm is very similar to a bulb but it doesn’t have the onion-like layers. Each corm will make lots of baby ones so when you dig up the clumps to divide, gently pull the corms apart to separate.

Watering and Maintenance

Crocosmia plants require regular watering, especially during dry spells. Keep the soil evenly moist but avoid overwatering, as excessive moisture can lead to root rot. Mulching around the plants can help retain soil moisture and suppress weed growth. During the growing season, you may also consider providing a balanced fertiliser every few weeks to promote healthy growth.

Propagation

In late autumn, after the flowers and foliage have died back, you can cut back to ground level.

After a few years, taller varieties of crocosmia can form large clumps and the plants have a tendency to flop if they become congested or are in an exposed, windy site. Lift and divide clumps that have become too big in late autumn or early spring, and replant the corms elsewhere. Dividing the corms helps rejuvenate the plants and prevents overcrowding.

Crocosmia has a tendency to spread – some more readily than others – and it can form large, dense swathes over time. The solution to keeping it in check is again, to dig up and divide larger clumps, either replanting the divisions elsewhere in the garden, or give them away to friends and family.

If you hanker for these beauties for your garden, look out for the potted plants in garden centres and nurseries now, or for dormant corms early in the new year which you can plant out in spring. Keep the corms somewhere cool, dark, and dry until you are ready to plant out.

Some crocosmias can become invasive. Crocosmia × crocosmiiflora, often referred to as montbretia, has ‘escaped’ from gardens into the wild, where it can crowd out more delicate native species so it is best not to grow it if your garden adjoins open countryside.