Crocosmia bulbs are native to South Africa and one of the easiest bulbs to grow. They belong to the liliaceae family along with lilies, tulips, lily-of-the-valley, bellworts, merrybells, dogtooth violets and about 4,000 other varieties. Crocosmia bulbs produce one of the tallest and most striking flowers of the family.
The plant grows from 2 to 4 feet in a single season. The bulbs produce up to 50 individual tube-shaped flowers that can be red, yellow, orange-yellow, and orange with splotches of other colors. The flowers start blooming from the bottom of the stalk to the top. They are late blooming bulbs with flowers appearing from July to October.
Crocosmia bulbs need full sunshine, at least 6 hours a day. They also need loose, well-drained, light soil. Crocosmia bulbs are hardy in zones 5 to 9, from the middle of the country to all but the hottest places in Florida and California, and in some places along the West Coast as far north as the Canadian border.
Plant crocosmia bulbs in the fall. If the soil is heavy or does not drain well, mix it with a good amount of sand. Plant the bulbs, with the pointy side up, 4 to 5 inches deep and 4 inches away from each other. Mulch well in the colder areas. They only need to be watered at this time if the soil is dry.
Keep the soil moist but not wet. You should not be able to squeeze any water out of it. Crocosmia bulbs only need fertilizer if the soil is very poor. The exception is when they are planted in containers. In this case, they need to be fertilized regularly. The bulbs will grow new bulbs.
When the plant is 3 or 4 years old, dig it up and divide the bulbs. You can then replant the original bulb and use the others to start new plants elsewhere. After the flowers have died back in the fall, they can be cut all the way back to the ground. Those in the cold areas have two choices. Either mulch them heavily over winter or dig them up and store them in a cool place to be replanted in the spring.
Crocosmia bulbs can be planted in a garden or used as container plants for patios or decks. They can be cut once a week all through the growing season for cut flower arrangements.