Once the blooming season is over, you can't just ignore those summer bulbs you planted (such as dahlias and gladiolus). Prior to the first killing frost, you need to dig up your summer bulbs (tuberous begonias being the major exception). And now's the best time to dig them out because the soil is still soft and easy to get through.
Dig bulbs up carefully and spray them down to remove any loose soil. Let them dry in the sun for a few days. (Bulbs must be dry before storing or they will rot.) Dust the bulbs with a fungicide and store in peat moss or wood shavings in a brown paper bag, open crate, netted bag or even old pantyhose. Store them in a cool, dark place (50-55° ) until time to replant.
Of course, some plants have particular needs; dahlias need a temperature just under 40 degrees, while gladiolus should be hung suspended in mid-air. For best results, consult your reference book or local gardening expert on how to store each type of bulb.