In order for the bulbs to have enough time to establish their roots, plant them about six weeks before a hard, ground freezing frost . However, as long as you can get a shovel into the earth you can still plant them. A good rule of thumb is to plant bulbs when the average nighttime temperature is around 40 to 50 degrees (usually during September or October). Keep in mind, planting bulbs too early can lead to fungal or disease issues. If you are unable to plant your bulbs right away, be sure to store the bulbs in a cool, dry place away from direct sunlight. Even if planted late, bulbs will spring into action and try to start root growth. They are programmed to grow and will do their best no matter how late you plant them. There is always the option of forcing your bulbs if you just cant get to planting them in the ground in time.
“A weed is but an unloved flower.”
-Ella Wheeler Wilcox