The care information provided in this section represents the kind of practical advice is available for all the plants in this web site if you subscribe to the monthly customized newsletter Yardener’s Advisor.
Most bulbs require very little care. Imperial fritillaries are no exception. They may need staking for support when they are in bloom, especially if there are high winds or driving rains. After the blossoms fade, cut them off down where the foliage begins on the stem. Allow the foliage to die back naturally. This is very important, since it is during this time that the leaves soak up the sun to help the bulb manufacture and store the energy it will need to bloom next season. Once the foliage has died back, clean it up and discard it to avoid disease problems in the flower bed. After several years the flowers will be noticeably smaller, which signals that the bulbs need to be dug up and divided. (See below).
Before and during bloom imperial fritillaries usually do not require special watering unless it is an unusually dry spring. However, after they have bloomed it is important to assure that they receive regular water from the rain or a sprinkler. This is the time when they are storing nutrients and growing roots for the next year. During hot, dry weather, water bulb beds thoroughly once a week. For information on products see the file on Choosing Watering Equipment
Feed fritillary bulbs once a year to assure their good health. After they have bloomed, sprinkle about 1 tablespoon of a granular fertilizer designed for bulbs on the soil around each bulb for the rain to soak in. Keep it at least two inches from the stem to assure that it does not touch and damage plant tissues.
Mulching and Weed Control
Spread a 1 or 2 inch layer of an organic material such as chopped leaves, shredded bark, or wood chips over the bulb bed to control weeds and conserve soil moisture during the growing season. In the winter a similar mulch helps to insulate the soil from extreme temperature fluctuations which heave the soil and may disturb bulbs. Remove mulch over bulbs in early spring to allow the soil to warm up and spare the new shoots the struggle to grow through several inches of mulch. For more information see the file on Using Mulch
Imperial fritillaries produce baby bulbs, called offsets, over time. Every 3 to 5 years, when the fritillary plants become crowded as indicated by smaller flowers, gently dig up the bulbs from the bed and separate the young offsets from the parent bulbs. Do this when the bulbs are dormant, shortly after the foliage has died. Replant as described above.