Dig up summer-flowering bulbs such as tuberous begonias, caladiums, cannas, dahlias, gladiola and tuberoses once their foliage has died back or as soon as they are killed by frost. You’ll want to gently clean the soil from the corms and tubers, but don’t wash them or force the tops off. They will shrivel and separate when they are ready. Store bulbs in a fine dry peat, sawdust, sand or vermiculite at no lower than 60 degrees with low humidity.