Hardy fall-blooming bulbs are an often-overlooked way to enrich the autumn garden. With proper site choice and care, they are low-maintenance and long-lived. Here are some of the best fall-blooming bulbs to try:
- Fall-blooming colchicum
- Fall-blooming crocus
- Autumn daffodil
- Autumn snowflake
Fall-Blooming Colchicums
Colchicums are often called “autumn crocus” because their blooms usually look like giant crocus blooms, but they are a separate genus. Most colchicums have more than one flower per corm (“bulb”). Here are some to try in your garden:
- Large-flowered doubles – These are the colchicums most often seen in general gardening catalogs and garden centers. Cultivars include pink hybrid ‘Waterlily’ (also sold as ‘Double Waterlily’), C. autumnale ‘Alboplenum’ (also sold as ‘White Waterlily’), and rosy C. autumnale ‘Pleniflorum.’
- C. agrippinum – The species has highly checkered, pinkish-purple flowers.
- C. bivonae 'Apollo' – Usually available as this cultivar, the large flowers are purple and finely checkered. It is thought to be an ancestor of many of the largest-flowered hybrids.
- C. byzantinum – Introduced to gardens in the late 1500s, the species has rosy petals. The most common cultivar is ‘Album,’ white with faint touches of purple.
- C. cilicicum – Very similar to C. byzantinum, it blooms later in a slightly darker color.
- C. speciosum – This species looks more like a tulip than most colchicums. The species, introduced to gardens in the 1800s, is violet. White ‘Album’ is the most common cultivar.
- Hybrids – Hybrid colchicums are very common. Some of the best include finely checkered, purplish-and-white heirloom 'Disraeli'; vivid purple ‘Violet Queen’; violet -edged, white-centered ‘Dick Trotter’; rosy-edged, white-centered ‘Giant’; ‘Harlekijn’/’Harlequin,’ white with a large purple band; deep purple ‘Poseidon’; and lilac ‘Lilac Wonder’.
Fall-blooming colchicums generally prefer compost-enriched, well-drained soil in full to partial sun. They are poisonous to animals. Handling the corms can cause skin irritation, so wear gloves while planting them.
Fall-Blooming Crocus
The most famous fall-blooming crocus is Crocus sativus, the source of the spice saffron, but there are several species with numerous cultivars from which to choose. Here are some species to try:
- Saffron crocus (C. sativus) – Despite what many catalogs claim, it takes thousands of blooms to make one ounce of saffron. Regardless, saffron crocus is a beautiful heirloom plant well worth growing. It has been cultivated for thousands of years. The species is lavender with darker purple veins and has striking red stamens (from which the spice is made). “Cashmerianus” is the most widely available cultivar; it has a reputation for growing better in cooler climates and being more floriferous than the species.
- Autumn crocus (C. speciosus) – This looks similar to saffron crocus but is easier to grow in most climates. The species, on the bluer side of violet than saffron crocus, was introduced to gardens around 1800. Commonly available cultivars include sky blue ‘Conqueror,’ heirloom white ‘Albus,’ deep purplish-blue ‘Oxonian,’ violet ‘Cassiope,’ and deep blue ‘Aino.’
- C. cartwrightianus – This crocus, widely believed to be an ancestor of saffron crocus, is pale blue with darker veins. The most common cultivar is white ‘Albus.’ Hardiness reports of this crocus vary widely.
- C. kotschyanus ssp. kotschyanus ‘Reliant’ (also sold as 'Reliance') – While the species C. kotschyanus has a poor reputation due to often having tiny or deformed flowers, this cultivar is as reliant as its name would indicate, bearing pale lavender blooms with delicate veining.
Fall-blooming crocuses like well-drained, rich soil. They prefer water in spring and autumn, and dry soil during their summer dormancy. They tend to be less weather-resilient than their spring cousins. Planting them by something that can support them – such as amongst groundcover in areas with autumn rains or on the leeward side of a sturdy plant in windy areas – will help weather-proof them and improve their display.
Autumn Daffodil
Sternbergia lutea, referred to by such names as “autumn daffodil” and “autumn crocus,” has the golden color of a daffodil and the shape of a crocus, and prefers sharply drained soil. It is a good companion to fall-blooming crocus, typically blooming simultaneously. It is more heat tolerant than many fall-blooming bulbs, but its reported coldest temperature varies tremendously, so experiment in your garden.
Autumn Snowflake
Autumn snowflake, Leucojum autumnale, is a relative of spring-blooming snowdrops (Galanthus spp.) that bears beautiful dainty white bells in autumn. It is animal-proof and grows best in sharply drained soil or rock gardens. Though many catalogs erroneously report it as quite hardy, it is generally considered to be hardy in USDA hardiness zones 7-9.
Sources for Bulbs
Quality American mail-order sources for fall-blooming bulbs include Odyssey Bulbs of Massachusetts, Brent and Becky’s Bulbs of Virginia, and Bulbmeister of Arkansas. Order cut-off time for these bulbs varies based on when the bulb should be planted, when it blooms, and when the mail-order company receives its stock. Plant fall-blooming bulbs as soon as possible after receiving them.
For information on a related topic, see Angela England’s Bulbs to Plant in the Spring.