May. A pure white form is called Scilla sibirica alba. Ornamental alliums are, in fact, members of the onion family. They are showy, hardy, easily grown, and come in a wide range of heights and colors. Courtesy U of S Horticultural Extension. Autumn is bulb-planting time, and once again the garden shops and catalogues are full of Dutch bulbs and the promise of another spring.
Roots develop from the plate when the bulb is actively growing.
When you purchase bulbs, they are in a resting or dormant state, and the roots are not present. Given adequate care, the larger the bulb planted in the fall, the better the quality of the flowers the following spring. Keep in mind, of course, that size will vary with the type of bulb. A hyacinth bulb, for example, will always be larger than a scilla bulb. The flesh of the bulb should be plump and fairly hard with no feeling of squishiness or looseness when it is compressed in the hand.