Fall Harvest.

1. For the best possible corms, and to get the best flowers next year, I wait until after first hard frost. I want to ensure the corms have had the longest possible time in the ground for energy storage.
2. Glads will need to be lifted (dug up). You will not be able to just pull them out because of their extensive root systems.
3. Once they are lifted, I cut the stems back to around 1/2”. Many cut the stems shorter because they dry better with no stem. Because I peel my corms before planting, the extra little stem that I leave on, gives me an easy starting point for peeling.
4.  Corms need to be sufficiently dried for storage. For me that’s usually 1-2 weeks. Cardboard flats work excellent for this. It’s usually in the drying stage that I clean up the corms. The old corm that was planted in the Spring, along with any roots get popped off and discarded. The white balls that you see with the new corms are cormlets. They could be saved if you want and planted in the Spring. They will take 2-3 years of cycling before you’ll get full blooms and large corms. If there are multiple new corms attached, they can be separated as well.
5.  Once the corms have been adequately dried, I treat with a little sulphur dust. I use Safers brand that can be bought at Canadian Tire, or most garden centres. Be sure to read and follow safety instructions on the container. The sulphur dust will act as an anti fungal and it will also kill a lot of bugs that will try and overwinter on the corms.
6. For storage, I use milk crates, bulb crates, and onion sacks. I have also used shoe boxes and paper bags. It is important that the corms can breath and that any moisture can dissipate. Do not store in plastic.
7.  Corms need to be stored cool, dark and dry. I have found that 2-4C is the absolute best temperature range. Under 4C for over 6 weeks will kill any thrips that may be on the corms. If you can’t store at temps that low, it’s ok to store them warmer. My father-in-law uses a shop that he keeps 12-15C over the winter. For those without a cool storage option, I have also recommended a basement closet or any closet that won’t be opened regularly through the winter. The temperature in the closet will tend to be cooler than the rest of the house. Wherever you are storing them, it’s critical that they stay dry and that they don’t freeze.
8.  I like to check them every month or so through winter. Mostly checking for mold or any moisture issues.