If wanting to overwinter garden vegetables in your cold room, there are a few things you ought to know. The first is this: not all types of produce are suitable for cold storage! Some decay quickly after they are harvested, such as garden greens (lettuce, spinach, kale, etc) and soft vegetables (beans, cucumbers, eggplant, peas, summer squash, tomatoes).
Those that store well are the hard vegetables (allium family, cabbage & kohlrabi, all tubers & root vegetables, winter squash). They are also known as “keepers,” and if you are serious about overwintering produce, you’ll make space for them in your garden!
The same is true for fruits: not all are suitable for raw winter storage! The best and most often over-wintered fruits include apples, citrus and pears (some grapes have a 2 month preservation life).
If planting an orchard with the intent of overwintering your harvest, choose from the above. Unless you live in the south, apples and pears begin and conclude your limited options!
Choose Produce According to Sub-Type
Within each type of produce, there are particular varieties known for their good storage qualities. Some apple ripen late-summer and go bad within weeks of picking, while others are hardy and come ripe at the perfect time (and temperatures) for storing.
If planting a garden with the intent of using cool room storage…read the seed information and package labels before buying! If vegetables are suitable for overwintering, it’ll say so. If not, assume its a summer variety, the pick-and-eat-or-process-now type!
Summer varieties may keep in cold storage for a time, but they aren’t the best option. Heirloom vegetables will be your best winter keepers…just make certain the labels outline them as such!
Plant at the Right Time for Proper Maturation
It’s possible to plant particular vegetables too early in the year. Depending on your zone, you’ll probably need a late planting of turnips, radishes and possibly beets. If root vegetables are left in the ground too long, the plants may begin dying back. Rot may begin forming on the underside of leaves, travel to the stem and from there into the actual root you wish to preserve through the winter.
Storing vegetables inevitably leads to decay and it will take place much quicker if the process begun before you harvest! Because you want to pull vegetables only after cold temperatures come, its important that you plant at the proper time to avoid decay and not only that, but also tough, woody roots!
The best method for learning about a 2nd or late planting in your climate and zone? Talk to a local gardener! They’ll be able to tell you specifics about your area that google doesn’t know!
Want to learn more? Be sure to read How to Cure Vegetables for Dry Storage.