What are the basic groups of bulbs?
There are two basic groups of bulbs planted in Oklahoma. Spring flowering bulbs, which you plant in the fall, and Summer flowering bulbs which you plant in mid to late spring. Since the purpose of this section is to explain things in simple terms all growth forms (bulb, tuber, corm, rhizome, etc.) will be called bulbs. Spring flowering bulbs such as tulips, daffodils, hyacinths, crocus, grape hyacinths, ornamental alliums, lilies and a plethora of minor bulbs can be planted in the fall. This should be done after the soil has cooled (early November) and can be done as late as early January (if you clean up after the holidays and find some bulbs you set aside in early fall). Some people like to refrigerate the bulbs before planting them. This is not necessary unless you will be waiting past early January to plant them. Our ground stays cool for the full 12 weeks bulbs need to fully mature the bloom here in northeast Oklahoma.
