Bulbs prosper in rich and well-drained soil.
It is advisable to turn the soil and to enrich it with humus, i.e. compost or composted manure. Soil with a neutral or slightly alkaline pH level (6.5 to 7.5) is ideal. The pH can be determined with a soil test.
When the bulbs are planted, bone meal or a bulb fertilizer will provide the necessary phosphorus for the bulbs to take root properly. Later, when the buds appear, a fertilizer for flowering plants can be applied. It is important not to exceed the amount of fertilizer recommended by the manufacturer, because any excess may burn the plant.
Fertilizing is a very important factor in bulb growth because it strengthens the roots and enables the bulb to acquire new reserves for the following growing season.
The other important factor is watering. The soil should be well moistened to allow the roots to develop normally. Substantial watering before and after blooming will produce larger bulbs. The first few centimetres of soil should be watered and then left to dry before watering again. During the flowering period, the soil should not be left dry.