Tender bulbs, such as caladiums and tuberoses, often cannot survive cold winter weather. Generally these are the spring-planted/summer blooming bulbs, corms and rhizomes. We need to dig them up in the fall for winter protection.
Here are some steps to help you be successful.
First of all, in order to avoid damaging the bulbs, it's best to use a spading fork to carefully lift the them from the ground. If the soil is dry, first moisten the area around the clump. Sometimes it's best to just dig the entire clump up at once and separate it later.
Inspect your bulbs for signs of disease or damage and toss any soft or cut bulbs on the compost pile. With a few exceptions, wash or gently brush off any soil that clings to the bulbs, except for bulbs that you want to store in pots or that need the soil kept around them. Leave the soil on cannas and caladiums and store them in clumps on a slightly moistened layer of peat moss or sawdust in a cool place. You can wash and separate them just before planting.
Spread the bulbs in a shaded place to dry, and then let them dry for a few days before storing. If possible, do not divide or separate bulbs before storing them. Discard any undersized bulbs unless you want to experiment with them; however they may take them a few years to grow to flowering size. When dry, store them away from sunlight in a protected area, like a cool, dry basement, cellar, garage cabinet or shed (if it does not freeze). Bulbs do best if stored at 60F to 68F. After drying you might want to dust with a fungicide to prevent rot or disease. You can store them either in open trays or in trays full of peat moss or vermiculite. Or, if you have only a few bulbs, you can keep them in paper bags hung by strings from the ceiling or wall. Be sure not to store your bulbs more than two layers deep and be sure that air can circulate around them and avoid high humidity conditions where they could rot. Check on your stored bulbs once in a while to make sure they have not been bothered by mice or insects and inspect them for rot. Remove and discard any that show signs of damage. Here's specific information on some of the bulbs we sell:
Move potted plants to a protected place. If in the ground in zones 7-8, mulch the plants heavily.
Lift after the foliage dies. Store in peat moss in a dark, protected area inside.
In zones 1-7 dig up the rhizomes before it frosts, dry, cut off dead leaves and brush off soil and store in a cool, dry place. Or let rest a month, then pot up for indoor winter color. In spring cut into several pieces making sure each piece has a growing eye. In Zones 8-10 mulch heavily.
Cut off the dead tops 6" above the soil in fall. In zones 3-7, lift and store. Cut in spring to divide. Mulch heavily in zones 7 and 8.
Once planted, Crinums do not like to be disturbed, so if you are north of zone 7 it's best to have planted them in pots that can be moved to a cool place for winter. In zones 7 and 8 mulch to protect them from unexpectedly cold winter weather.
Lift the corms in the fall after the first hard frost. Store corms in a cool dry place. You might want to leave a few in the ground under mulch to see if they are hardy in your area.
Cut back to 6 inches and dig up. Let dry thoroughly and wrap in newspaper
After lifting, cut the stem 2 inches above the corm and leave them out to dry. Leave the corms out to dry for up to 3 weeks. Then break the cormlets off the old mother corm, and store them. You can also save the smallest 'cormlets', which will bloom in 2 or 3 years. The original mother corm should be discarded.
Tuberoses In zones 7 and 8 mulch heavily during the winter months. Plant out in early spring. They may be started in pots for earlier bloom. In the spring separate off the bulbets from the base of the big bulb and discard the old bulb.
Mulch in winter. They are all tender except candida, which will go to zone 5. Lift the tender ones after the first frost. If grown indoors give a 3 month dry rest after the leaves have died.
I'd love to have your input - in which zones have you grown any of the tender bulbs?