Hello, I’m Hilary Dahl and this is Encyclopedia Botanica, a weekly podcast about edible gardening. This week we will be talking about curing and dry storage techniques for onions, garlic and winter squash.
Certain crops can be cured before eating and storing so as to improve flavor and increase storage life. Curing is the process of holding a crop at a relatively high temperature for a short period after harvest. Because the curing process varies by crop, we’ll discuss a few specifics here.
Let’s start with onions. Onions are, in my opinion, some of the most satisfying crops to grow. They are among the first transplants to be tucked into the early spring garden, and are ready to harvest at the onset of peak harvest season, a harbinger of the forthcoming abundance. Luckily the crops are happy to be stored away for us to enjoy during less bounteous times of year. However, to store onions for more than a few weeks it’s necessary to cure them. Curing onions allows the outer layers to dry out and tighten, forming a protective wrapping around the bulb.
Bulbing onions are ready to harvest once the stems start to turn brown and die back. The tops will also start to flop over and portion of the bulb will usually be above the soil surface at this time. To harvest, lift the entire plant from your garden beds. If the weather is warm and sunny, you can leave the onions in your garden for several days to begin the curing process- just be sure to pull them undercover if it starts to rain. We’ve been having funny weather here in Seattle this summer, and I accidentally left all 34 of my onions out during an overnight downpour a few weeks ago. I have them back out in the sun to continue curing, but I am pretty sure that this soaking has compromised the storage life of my onion crop.
If you have left your onions out in the sun, you’ll want to move them to a covered, well-ventilated location after a few days. This could be a covered car port or a porch, or a greenhouse or shed with the doors left open. Lay the onions out on a surface that is off of the ground. A metal outdoor dining table- the kind with the mesh top- work really well because they allow air circulation around the bulbs. Leave your onions like this until the tops are fully browned and dried (this should take about two weeks). Once the tops are fully browned and dried, you can trim the roots and tops within 1 inch of the bulbs and move them into long-term storage. Depending on the quantity you grew, a long term storage location could be a large mesh bowl on your countertop, a few cloth-mesh bags, or a large crate.
Depending on the variety, onions will have different storage capacities. Generally, yellow types store longest, but be sure to read about the varieties you are growing, or planning to grow before deciding which ones to cook with first. If properly cured and stored, it is possible to eat bulbing onions from midsummer through the following spring.
Next I want to touch on storing garlic. As with onions, garlic must be cured for long-term storage. Harvest garlic when about half of the leaves are brown and half are still green. If you wait until the entire plant is brown, the storage life will be compromised because the cloves will have already started to separate and won’t have that nice thick layer of paper to protect the cloves. When choosing which heads to store, the ones with the tightest grouping of cloves and thickest paper are the heads that will sure the best and keep the longest.
To cure, do not wash your garlic with water, simply knock off any large clumps of dirt that may be clinging to the plant and the roots. Do not remove the cloves from their papery wrapping. Unlike onions, garlic does not benefit from time curing in the sun. Immediately hang the plants, fully intact, in a warm, dry, dark place for several weeks. This will increase the storage life. After 4-6 weeks of curing, the garlic stalk and roots can be trimmed back to so that the bulb resembles one that you would buy at the store or farmers market. This trimming of the stalk and roots is not necessary, but does make using the garlic a little easier when it comes time to cook with it. The smaller heads also require less storage space.
Lastly, I’d like to discuss winter squash and pumpkin storage. As with both onions and garlic, winter squash and pumpkins do not need to be cured before eating, but they will keep best if cured for 7-10 days. For best flavor, wait to harvest winter squash and pumpkins until their stems are dry and they have a yellowish/brownish mark where they have been in contact with the ground. Leave at least 4 inches of stem on your fruit. A broken stem exposes the fruit to rot, so be careful when harvesting and transporting fruit. If the stem breaks off completely, be sure to use it within a few weeks of harvest.
Fruit that is exposed to freezing temperatures will not store long, so make sure to harvest winter squash before the first frost in the fall. In general, temperature extremes reduce storage life, so aim to keep your winter squash in a dry location that stays between 50 and 55°F.
A harvested winter squash continues to breathe or respire. During the curing process, the skin becomes harder, forming a protective layer over flesh. That harder skin slows respiration, which ultimately improves fruit keeping quality. Harder skin also resists rot better.
Unlike onions and garlic, you will want to wash the squash with a very mild solution of 1 tablespoon of bleach to 1 gallon of water before curing, to eliminate fungal spores. Squash cures best at 70-80 degrees Fahrenheit. Since we harvest it late in the season, you might have to create the ideal conditions instead of relying on nature. Once the fruit has been cleaned, you can bring it indoors and place it in a sunny window or warm room. After 7-10 days of curing, the fruits can be moved to a well-ventilated shelf or counter for long-term storage. I like to keep my squash in place that is in plain sight so I don’t forget about them and so I can catch any that may be starting to go bad.
Well, hopefully that covers some of the basics of curing and dry storage. As always, there is plenty more to discuss on the topic and we’ll continue to dig into these concepts in future episodes. Feel free to leave any questions you may have on the podcast transcript on our blog. I’d also love to hear your what you think about the podcast so far so leave a review on iTunes! Happy curing and I’ll see you next week!