Crown imperials are strong-growing bulbous plants, making rapid growth in the spring, flowering during April/early May and dying down in early summer.

Planting

They need a deep, rich, well-drained loam soil, preferably alkaline, and a warm, sunny position where they can be left undisturbed for many years.

Where soil conditions are less than ideal it is advisable to thoroughly prepare the site before planting, digging in some well-rotted manure or rich leafmould and grit. Simply putting grit in the bottom of planting holes on heavy soils will achieve little. Add a dressing of Vitax Q4 Fertiliser at about 140g per sq m (4oz per sq yd) before planting in the early autumn.

Plant

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes.

It is claimed that planting the bulb on its side may prevent rot when the bulb is

Dormancy refers to a period of inactivity in plants, during which they slow down or stop their growth, conserving energy and resources. This is a natural process that helps them survive harsh conditions, such as winter or drought. Dormancy in seeds is a mechanism that prevents them germinating until environmental conditions are favourable for growth.

Add a mulch of well decayed

Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

The period of time when an individual plant is in active growth. This will depend on the local climate and light levels, and can vary between different plants, although it is broadly from spring to autumn.

growing season

Containers

Crown imperials rarely do well on heavy clay soils and, in such situations, are best grown in raised beds with good drainage or in containers. For the latter, use a mix of equal quantities of John Innes No.3 and multipurpose growing media with the addition of about 20 percent grit. Incorporate Vitax Q4 at 5g/litre. Do not use controlled release fertilisers which are unsuitable for spring flowering bulbs in containers due to excessive nutrient release.

Aftercare

In good growing conditions crown imperials will readily form large clumps. If a well-established colony begins to flower poorly then lifting in early autumn when dormant, thoroughly improving the soil and replanting, or moving to a new site may be sufficient to restore satisfactory flowering. The bulbs may take a year or two to re-establish.

Fritillaria imperialis 'Aurora': Shorter than most at 60cm (2ft) with orange flowers veined red

F. imperialis 'Maxima Lutea' AGM: Tall, erect stems to 1.2m (48in) with half a dozen or more large nodding, bell-shaped bright yellow flowers

F. imperialis 'William Rex': Intense reddish orange flowers on dark bronze coloured stems to 90cm (3ft)

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