Crown imperial 'Rubra Maxima' Fritillaria imperialis 'Rubra Maxima'

Water

Crown imperials require consistent moisture during the spring growing season but do not like to be overwatered. They should be watered deeply once a week with about 1 gallon of water, allowing the soil to dry out slightly between waterings. It's crucial to avoid waterlogged conditions as this can lead to bulb rot. Increase watering if there are extended periods of hot and dry weather. During the dormant season in summer after the leaves die back, reduce watering significantly to mimic their natural habitat conditions.

Light

Crown imperials thrive best in full sun to partial shade conditions. They should be planted in a spot that receives at least 6 hours of direct sunlight each day. An ideal spot would be one that is sheltered from strong winds but still gets adequate light, as too much shade can cause the plants to grow poorly and produce fewer flowers.

Temperature

Crown imperials are hardy in zones 5 through 9, tolerating winter cold down to temperatures of about -20°F. They prefer a cool to mild climate with temperatures ranging ideally between 50°F and 70°F during their growing season. During their dormant period in the summer, they can withstand higher temperatures as long as they are not excessively hot and dry.

Pruning

Pruning of crown imperial plants is primarily for removing spent flower stems to tidy up the plant after blooming and to prevent seed formation, which can divert energy from the bulb. Cut the stem close to the ground level when the flowers have faded, usually in late spring. Apart from this annual pruning, little to no further pruning is necessary unless removing damaged or diseased foliage.

Cleaning

As needed

Soil

Crown Imperial requires a well-draining soil mix with a slightly acidic to neutral pH of 6.0-7.0. A mixture of loam, sand, and compost is ideal for ensuring good drainage and fertility.

Repotting

Crown Imperial bulbs should be repotted every three to five years, ensuring the soil is refreshed and the bulbs are not overcrowded.

Humidity & Misting

Crown Imperial thrives best in moderate humidity conditions; it does not require high humidity environments.

Suitable locations

• Indoor

  Place Crown Imperial in a bright spot, ensuring cool temps and good air flow.

• Outdoor

  Plant in well-drained soil, full sun to partial shade, protect from strong winds.

• Hardiness zone

  5-9 USDA

Life cycle

The Fritillaria imperialis 'Rubra Maxima', commonly known as Crown Imperial, begins its cycle when a bulb is planted in the ground, usually during the autumn months. As winter passes, it enters a period of dormancy where underground development occurs. With the onset of spring, the bulb sends up a sturdy stem, leaves, and a crown of red, bell-shaped flowers that give it its reputation as a striking garden specimen. After flowering in spring, the plant's foliage dies back, and the bulb enters a summer dormancy phase, conserving energy for the next growth cycle. In this phase, the bulb can be left in the ground or be dug up, divided, and replanted to propagate new plants. The bulb re-emerges annually from its dormant state, completing its perennial life cycle.

Propogation

• Propogation time

  Spring

• The Crown Imperial Fritillaria, known as Fritillaria imperialis 'Rubra Maxima', is typically propagated by bulb division. This is best done in the late summer to early fall, after the foliage has died back and the bulb is dormant. To propagate, carefully dig up the parent bulb and gently separate the smaller bulblets that have formed around its base. These bulblets can be replanted immediately, ensuring they are planted at a depth three times their height; for a 2-inch (5 centimeters) bulblet, plant at a depth of 6 inches (15 centimeters). The separated bulblets will take a few years to reach flowering size, but once they do, they will produce the same striking, bell-shaped, reddish-orange flowers that make this plant a garden favorite.