What Is a Crocus? All About These Springtime Flowers, Including How to Grow and Care for Them
The crocus flower, or Crocus spp, is a late winter or early spring perennial famous for producing some of the first blooms of the new year—while they typically emerge at the start of spring, you may notice their colorful heads bursting through the ground even before all of winter's snow has melted. The easy-to-grow flowers are part of the iris family and are a favorite among those living in areas that see cooler winter temperatures, as they generally indicate that warmer weather is on the way.
What Is a Crocus Flower?
Crocus grow just inches above the ground and produce cup-shaped flowers that are a half-inch to one-inch in size, according to Adrienne R. Roethling, director of curation and mission delivery at Paul J. Ciener Botanical Garden. "They are a symbol of happiness, often blooming in winter, sometimes through a blanket of snow or on a miserable day," she says. "They reflect hope that spring is around the corner." If you're looking to add some to your garden, Roethling suggests planting them in a large grouping, as the bright purple and white or yellow flowers that emerge are perfect for brightening up rock, patio, or smaller gardens. Although crocus is well known for being part of a bulb group, it's actually a corm, explains Venelin Dimitrov, lead horticulturist at Burpee. "A corm or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat."
How to Grow Crocuses at Home
There are more than 80 different species of crocus, but the most popular are the spring flowering crocus known to gardeners as the Dutch hybrids Crocus vernus, explains Dimitrov. "They like open ground, but they can do well in the light shade under deciduous trees and shrubs," he says. "Crocus requires well-drained soil that dries out in the summer, [and they're] not fussy about the Ph." The spring showstoppers do best in USDA hardiness zones three to eight. They are considered to be wildflowers by some, and very easy to grow.
If you'd like to add some crocus flowers to your garden, Roethling says it's easiest to do it by planting bulb-like corms. "The cost of most crocus [corms] are so low that it wouldn't be worth the waiting period to get a seed to actually perform to its fullest," she says. "And, the more you buy, the price breakdown gets less." Since she thinks the spring blooms make the biggest impact when planted in large groupings, she advises gardeners to plant 100 corms (as opposed to 10).
Using Fertilizers and Amendments
While the flowers aren't fussy, they are easy to fertilize, which Roethling says you can do using something like BulbTone, which is an organic product made by Espoma. She suggests applying it to your garden in mid-winter, just prior to when the flowers begin to bloom. "For individual masses, sprinkle just a quarter cup over the planted area," she says. "For larger beds, sprinkle four cups worth (five square feet)."
Enjoy a Fall Variety
You don't have to wait for spring to enjoy crocus blooms in your garden. According to Amanda Duncan, horticulturalist with Fast Growing Trees, there are also a few fall-blooming varieties. "Fall blooming (often called saffron crocus) are less desirable than spring but are a nice autumn surprise when they appear," she says. "Colors include, blue, yellow, purple, pink, white, and striped two-inch wide by two- to-six-inches tall." The fall blooming variety can pull double-duty and be put to use in your kitchen as well. "Saffron crocus can be harvested as a spice for cooking."
Pests and Problems
Roethling says that crocus are a favorite among four-legged critters, who can get quite hungry after a long winter. "To protect the [corms], mix PermaTil into the soils," she says. "PermaTil is a baked slate rock aggregate and unbreakable." Underground pests like voles can't penetrate through it, so they'll move along to find other food sources. "For critters above the ground, find a spray containing hot pepper," she says. "You may have to spray repeatedly depending on the weather and for the wildlife to take a hint." Dimitrov says you can also try "dried blood" or "bone meal." The products are usually sold as soil amendments or fertilizers, but they can double as animal repellants as well.