How to Dry Out Canna Bulbs
Cannas are large and exotic plants that bloom in a variety of colors including orange, red and yellow. Cannas have underground root structures that are often referred to as bulbs and even sold as bulbs, but in fact, they are technically tuberous roots. Since the canna roots are tender, they need to be stored during the winter. However, prior to storing canna bulbs (tubers), they need to be thoroughly dried, which is a process sometimes called curing.
Wait until after the first frost. Cut off the dying foliage so that about two inches remains above the soil.
Dig straight down about 4 inches around the perimeter of your plants. Use a shovel or garden fork. Then, pull up on the handle to gently lift the bulbs out of the soil.
Shake and remove excess soil with your hands. Do not wash canna bulbs.
Lay the bulbs out on newspaper or an elevated screen so both sides are exposed. The bulbs should not be touching one another.
Store the bulbs in a cool area, out of the sun and wind. Ideal temperatures for drying canna bulbs is 60 to 70 degrees F, so drying them indoors is usually sufficient. However, if your home is warmer than that, place them in a closet or in the coolest area of your home.
Check on your bulbs every other day for the first week and then every day the second week. Do not allow your bulbs to shrivel up. Once the remaining foliage is completely dry and can be easily pulled off, you can remove the cannas for long term winter storage. The drying process usually takes about two weeks.
Store your canna bulbs for the winter. Pull off any remaining stems. Place the bulbs in an open container under dry sand, peat moss or vermiculite. You can also put them in a sealed heavy duty plastic bag without any soil. Place the bulbs in a cold area that is between 40 to 50 degrees F, such as a garage, attic or crawl space.