Crown imperial 'Rubra' Fritillaria imperialis 'Rubra'

Water

Crown imperials should be watered regularly during their growing season in the spring, with increased frequency during dry spells, aiming for about 1 inch of water per week. It is important to avoid overwatering as these plants are prone to root rot, so ensure the soil is well-drained and the top inch feels dry to the touch before adding more water. In the dormant season, after the foliage dies back, watering should be reduced significantly to prevent the bulb from rotting. A deep, less frequent watering is beneficial as it encourages the roots to grow deeper into the soil.

Light

Crown imperials thrive in full sun to light shade. They perform best when they receive at least 6 hours of direct sunlight daily. The ideal spot for these striking plants is in a South-facing garden that provides ample sunlight while protecting them from harsh late-afternoon sun, which in some areas can be too intense. Avoid deeply shaded areas where they may not bloom as profusely.

Temperature

Crown imperials are hardy in USDA zones 5 through 9, tolerating temperatures down to about -20°F for brief periods. They prefer cooler conditions during their growing season, with ideal temperatures ranging from 60°F to 75°F. It's crucial that they have a period of winter chilling at temperatures below 50°F to ensure proper dormancy and subsequent flowering.

Pruning

Crown imperials do not require regular pruning, but spent flowers can be deadheaded after blooming to maintain a tidy appearance and prevent self-seeding. Foliage should be left intact until it yellows and dies back naturally, as it provides energy for the bulb for next year's growth. Pruning is best done in the late spring or early summer, following the period when the plant has bloomed.

Cleaning

Not needed

Soil

Crown Imperial prefers a well-drained, fertile soil with a pH of 6.0-7.0. A mix of loam, sand, and compost is ideal to ensure adequate drainage and nutrient content.

Repotting

Crown Imperials typically do not require frequent repotting and can be left undisturbed for several years, as they do not appreciate being moved. Repot them only if necessary after flowering, every 3-5 years.

Humidity & Misting

Crown Imperial thrives in average outdoor humidity levels and does not have specific humidity requirements as long as it is planted in well-drained soil and is not overwatered.

Suitable locations

• Indoor

  Ensure bright light, cool temp, minimal water for Crown Imperial.

• Outdoor

  Plant in sun, well-draining soil, frost-hardy, minimal care.

• Hardiness zone

  5-9 USDA

Life cycle

Fritillaria imperialis 'Rubra', commonly known as Crown Imperial, starts its life as a bulb, which is planted in the ground in late summer to fall. In the spring, from this bulb, a shoot emerges from the soil, which will develop into a tall stem bearing lance-shaped leaves and a prominent flower at the top, characterized by a stunning red, bell-shaped bloom that appears in mid to late spring. After flowering, the plant goes through pollination, often by bees, and if successful, it will produce a fruit capsule containing seeds. As the flowering ends and summer progresses, the above-ground foliage of the Crown Imperial withers and dies back, allowing the plant to enter a period of dormancy. During the dormant period, the bulb remains underground, storing energy for the next growth cycle. With the return of favorable conditions the following spring, the cycle begins anew with the bulb sending up new shoots, thus continuing its perennial life cycle.

Propogation

• Propogation time

  Spring-early summer

• The most popular method of propagation for Fritillaria imperialis, commonly known as Crown Imperial, is by bulb division. The ideal time for this activity is in late summer or early fall after the foliage has died down. To propagate by dividing the bulbs, carefully dig up the parent plant and gently separate the smaller bulblets from the base of the main bulb. Each bulblet should have a portion of the basal plate to ensure successful growth. These can then be replanted immediately at a depth of about 6 to 8 inches (15 to 20 centimeters), spaced 10 to 12 inches (25 to 30 centimeters) apart in well-drained soil with an addition of organic matter. It's crucial to plant them in a location that receives full sunlight to partial shade. Water the newly planted bulblets thoroughly to encourage root development.