How to Plant, Grow, and Care For Crocosmia
Crocosmia bursts into flower in summer with fiery bloom spikes that add visual interest and draw pollinators. Gardening expert Katherine Rowe explores the zest and carefree nature of the bulbous perennials.
Crocosmia brightens the border with sword leaves and blooms in....
bright orange, reds, and yellows. They emerge in summer among strappy leaves and flower through fall, providing nectar and pollen for bees, butterflies, hummingbirds, and other pollinators.
Eye-catching in both sun and dappled shade, the old-fashioned favorites delight with easy care. With consistent moisture, crocosmia happily naturalizes (sometimes too happily).
Crocosmia is vibrant in a group, offering contrast in texture and color. Here, we’ll explore how to grow these bulbous perennials for dynamic interest.
What is Crocosmia?
The Crocosmia genus houses about seven species, with thousands of cultivars, many of which are Royal Horticultural Society Award of Garden Merit recipients for their bold blooms and ease of growth. Their fiery trumpets enliven the border with tubular flowers on gently arching scapes. The heirlooms also make striking cut flowers in fresh florals.
These low-growing perennials form clumps through spreading corms to create colonies. The spiked flowerheads appear in mid-summer for color through autumn. Related to gladiolas in the Iridaceae (iris) family, bloom spikes hold two rows of petaled trumpets in tapered sprays. The genus name derives from the Greek krokos, or “saffron,” and osme, “smell.” The flowers emit a subtle scent, intensified when dried petals, leaves, and stems steep in hot water.
Crocosmia, also called montbretia, copper tips, or falling stars, make lovely groupings in borders, cottage gardens, pollinator plantings, and cutting gardens, and naturalistic arrangements. Pair them with bananas, canna, flowering ginger, and agapanthus for a tropically-inspired display. Combine them with other perennials like salvia, dahlia, coneflower, rudbeckia, and ornamental grasses for a full-color panorama. Crocosmia also offers vertical interest in containers.
Characteristics
The South African natives hold their blooms for a long time in reds, golds, and bicolors. Bloom sprays open from the bottom to the top with a symmetrical flare. Slender, strappy foliage is medium green with a fan of blades.
Upper growth stems from underground corms, thick, starchy, bulb-like roots that can be flat or round with fibrous layers. Some species spread vigorously in their optimal growing conditions, leading them to be invasive in some areas. Crocosmia x crocosmiifora is a popular ornamental that escapes garden cultivation. Most cultivars are better behaved.
Avoid planting the genus if aggressive in your region, which can displace other plants, including native species. Forming a dense mat, crocosmia is a competitor for water, sunlight, and nutrients. Thin and divide the colony to keep it from spreading out of bounds.
After flowering, bright green seedpods emerge, extending the interest and providing forage for birds. In their optimal conditions, they’ll drop, scatter, and yield seedlings.
With wildflower qualities, montbretia are carefree growers. Deer and rabbits mostly avoid them, and they have few pests and diseases. Hardy to USDA zone 6, they benefit from extra winter protection or lifting and storing corms in zones 5 and lower.
Native Area
Native to southern Africa, from Sudan to South Africa to Madasgar, Crocosmia is indigenous to provinces in southeastern Africa where they grow in moist grasslands and along streambanks.
Planting
Spring offers the best planting conditions with warming soils that foster quick sprouting. Start with corms or nursery potted specimens. For corms, plant them three to five inches deep with a close spacing to allow for a six-inch spread. Aim to have the slightly pointed end facing upward and the flat root end pointed down.
Plant potted nursery selections anytime from spring through fall, avoiding dry spells and heatwaves that can stress new plantings.
In cold climates at the lower hardiness zones, lift the bulbs for planting in the spring. The shallow-rooted specimens are easy to dig. Clean and dry the bulbs to store in a cool, dry spot over the winter. Plant them after the threat of spring’s final frost passes.

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