How to Grow & Fertilize Alliums

Find an appropriate growing site. Plant alliums in areas of full sun and in a well-drained soil for best growth. The plants adapt to a range of soil types from poor to fertile as long as it is well-drained. Though the plants prefer moist soil, they also tolerate dry soils.

Plant the dormant allium bulbs in fall in a hole that is three times the bulb diameter. If you are using pot-grown plants, the best time to plant these is during spring or fall. Plant these at the depth they were growing in the pot.

Plant the taller, nonspreading species at a distance of about six inches. Grow smaller species of alliums at a distance that is half their height.

Monitor the growth. Let the foliage of alliums grow completely yellow during fall before you cut it off. The leaves create food for next year's growth and store it in the bulbs.

Propagate the plants by separating the little offsets that grow from the parent bulbs. Some species of alliums grow little bulbs called bulbils within their flower heads. Pick these and plant like seeds to grow new plants.

Fertilize the alliums. Avoid adding inorganic fertilizer to the planting soil directly as this can burn allium bulbs and also causes bulb rot. You can add organic fertilizer directly to the soil. Use specially formulated 9-9-6 allium fertlizer or an organic fertilizer formula of 5-10-12 during fall, as recommended by "Georgia Gardener's Guide."

Deadhead the spent flowers regularly as this helps to conserve plant energy otherwise spent in the production of seed.