Fritillaria imperialis: Time to Plant Pineapple Lilies
I wish it hadn’t taken me so long to grow Fritillaria imperialis. I guess I thought these exotic-looking flowers would be difficult. But now I know: exotic they are, difficult they’re not. Here are a few things I have learned about growing Fritillaria imperialis, which are also called crown imperials or pineapple lilies.
What to Know About Fritillaria Imperialis
All fritillarias are members of the lily family. Though the flowers look very different, their foliage is actually quite similar. Like lilies, the plants don’t have branches. The glossy leaves of fritillaria imperialis encircle the main stem and are attached directly to it. Additional leaves form a topknot above the flowers.
Fritillaria bulbs have scales like lily bulbs, but their scales are fused rather than being separate. The bulbs are more than twice the size of a regular lily bulb and much heavier. When handling them, you will notice they have a peculiar smell. In fact, all parts of the plant emit this same slightly skunky odor. This is what makes Fritillaria imperialis distasteful to garden pests including rabbits, voles, squirrels and deer.
Spring Flowers That Always Get Noticed
Of course the most distinctive thing about Fritillaria imperialis is the flowers. Each bulb produces one perfectly straight, glossy black stem. On top is a crown of bell-like flowers and a crazy hairdo of spiky foliage. Though the plants aren’t particularly tall (30-36″), their unusual appearance makes them an un-missable feature in the garden.
The two most commonly available varieties of Fritillaria imperialis are Rubra maxima, with orange flowers, and Lutea maxima, with bright yellow flowers. Both of them bloom in mid-spring, toward the end of peak daffodil season. Every part of the show is entertaining — from earliest bud to full bloom. Their long-lasting flowers guarantee weeks of enjoyment.
Fritillaries have a reputation for being more finicky than other fall-planted bulbs. Here’s how to keep them happy:
Plant the Bulbs in Well Drained Soil
Fritillaria bulbs are susceptible to rot, so it’s particularly important to plant them in well drained soil. As a precaution, you can dig a slightly deeper hole and put a shovelful of sand under the bulb. Another option is to plant the bulb on its side so water is less likely to collect in the hole on the top of the bulb. When the stem emerges in spring, it will head for the sun and grow just as straight as if you had planted the bulb upright.
Give the Plants a Warm, Sunny Spot
Fritillaria imperialis prefers full sun. As with most spring-blooming bulbs, the plants will also grow in partial shade, but full sun will give them the best chance of returning with a second year of flowers.
Ideally, crown imperial bulbs should spend the summer in soil that is warm and dry. They want the same semi-arid growing conditions of their native habitat in Afghanistan, Turkey, Iran, Iraq and Pakistan. The soil in my garden couldn’t be more different. It’s cold and wet almost all year-round.
Fritillaria imperialis is rated as winter hardy in zones 5 and warmer. I have found them to be winter hardy in zone 4B, but the plants don’t come back reliably. That may be a function of the cold, but more likely the wet. So I replant a few fresh bulbs each fall, just as I do with tulips.
Plant the Bulbs in Early Fall
While most fall-planted bulbs have a protective covering (called a tunic) that helps prevent moisture loss, lily and fritillaria bulbs are naked. This makes them more perishable, so the less time the bulbs out of the ground the better. Purchase fresh, properly stored bulbs as soon as they are available, and get them planted by mid-October.
Some Fine Print About Fritillaria Imperialis
Though pineapple lilies are rarely bothered by deer or rodents, as members of the lily family, they are vulnerable to the red lily leaf beetle. If these pests are a problem in your area, you’ll need to control them. Fortunately, the foliage only needs to be protected until it dies back to the ground, which happens about a month after flowering.
Here’s one other thing to know about growing fritillaria. In any given batch of bulbs, a percentage of them tend to be “blind.” These are bulbs that come up and produce foliage, but do not produce a flower. This behavior is somewhat of a horticultural mystery. It’s not about the size of the bulbs. Just an annoying characteristic of the species. Since there’s no way to know ahead of time which bulbs will not bloom, plant a couple extras so you’re not disappointed.