Answer: Your Allium may very well have produced viable seeds and you can try to germinate them, but they are difficult to germinate and you might not have 100 percent success. Knowing that, here's the best way to go about it:
Place seeds in a plastic bag together with moist growing medium and refrigerate for 30 days. Then remove and sow in trays, just on the surface of moistened seed starting mix. (Seeds need light to germinate.) The seeds will sprout in 14-365 days when kept at 55F - 65F degrees. Grow the seedlings in flats for 1 year, then pot up singly and sink pots into the ground outdoors in spring. After they are 2 years old you can remove from the pots and plant directly in the garden.
A good, all around book on propagation is "The Complete Bood of Plant Propagation" by Graham Clarke & Alan Toogood, published by Ward Lock Books, ISBN# 0-7063-7079-1.
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