Bulbs should be bought in specialised shops.  Preferred temperature is over 20°C. Plant the bulbs at a distance of around 3 cm with the flatter part towards the bottom and turn the point of the bulb upwards.  These should be covered with a thin layer of top soil.

Harvest when you wish, but after the plants have grown to a minimum height of 10cm. Moist soil, not overly watered.