Harvesting Vegetables

Tips on Harvesting and Storing Potatoes

Potato harvesting generally begins at summer’s end. Photo: http://www.thecapecoop.com

Yes, in the Northern Hemisphere, it’s that time of year again: late summer and early fall is potato harvesting season. True potatoes, that is: Solanum tuberosum. Sweet potatoes (Ipomoea balatas), a very different and unrelated plant, are much slower to mature.

Of course, there are early, mid-season and late varieties of potato, some ready as early as July in some climates, others not until October, but they all show they’re ready to be dug up when their foliage starts to yellow and die back. That can be a scary thing if it’s the first time you’ve grown potatoes—you may think you’re losing your crop!—but that’s how it happens. 

And do note that whether your potatoes bloom or not is not a factor. Some do, some don’t, depending on your climate … but they all produce tubers.

Of course, you can harvest tubers early, while the leaves are still green and healthy. These are “new potatoes”: small and very tasty, but they don’t store well. For potatoes that will last through the winter, wait until the foliage dies back.

A garden fork is a handy tool for harvesting potatoes, but not absolutely necessary. Photo: thecountrybasket.com

Harvest on a dry day, preferably when the soil is quite dry as well. A garden fork is a useful harvesting tool, as you’re less likely to damage tubers than with a shovel. There is even a special flat-tined fork called a potato fork specially designed for potato harvesting. Any tubers you do damage should go straight to the kitchen: they’re not likely to store well. 

Curing Potatoes

Potatoes being cured. Photo: http://www.ourstoneyacres.com

To store well, potatoes need to be cured (hardened off). This treatment helps thicken their skin and, usually, the thicker the skin, the better they store. It also allows minor nicks and scratches to heal over.

With a soft brush or cloth, brush off or wipe off as much soil as you can. Some people like to hose theirs down to remove soil and that’s fine in dry climates, but a bit risky in humid ones, as rot can set it. And, as any gardener will tell you, a little dirt never hurt anyone. Leave any thorough cleaning until just before you cook them.

Now, place the tubers in an aerated box or container or spread them over newspaper and, if they’re in the sun, cover with a cloth (don’t expose tubers to too much light). Place in a cool, dry, well-aerated spot, like a tool shed or garage. Temperatures of 45 and 60˚F (7 and 15˚C) and very high humidity (85 to 95%) are ideal for curing. Ten to 14 days are all that are needed to cure most potatoes.

Storing

Give cured potatoes a once-over, removing bruised, soft or discolored tubers. 

The root cellar is the traditional place to store potato tubers. Photo: foodal.com

If you’re just hoping to keep your potatoes for a month or two, say until Christmas, you can store them pretty much anywhere that isn’t hot and dry. For longer storage, until spring, though, you’ll need distinctly cool, humid conditions. Avoid really cold spots, though, below 40˚F (4˚C), as the tubers tend to sweeten and then won’t fry well, so the fridge is out. Above 60˚F (15˚C), however, they dry out. So you need “cool but not cold.” A root cellar is ideal, but not many people have one any more. You should be able to find a cooler spot in a basement or garage, an unheated entrance, or maybe an attic. 

You can store tubers loose in bins or boxes, but they seem to store longer in perforated plastic bags, probably because they then profit from greater humidity. 

Green potatoes, caused by exposure to sun, are bitter and, in fact, poisonous. Cut off the green part before cooking. Photo: indianapublicmedia.org

And you have to keep tubers in the dark. Potatoes exposed to too much sunlight will turn green and become poisonous (I kid you not!) 

Finally, don’t store them near ripe apples, as the latter give off a toxic gas, ethylene, that stimulates premature sprouting.

Inspection

Sprouting potatoes are still edible, but it’s a sign their storage life is coming to a close. Photo: theconversation.com

Check your potatoes once a month or so. Especially be aware of softening, the first sign of rot, as one rotten potato will quickly spread rot to other potatoes. As winter wears on, some will inevitably start to sprout and then shrinkage occurs. Use these first!

Mostly, though, just enjoy your potatoes. They really aren’t that hard to keep!

Larry Hodgson is one of Canada’s best-known garden communicators. After studies at the University of Toronto and Laval University where he obtained his B.A. in modern languages in 1978, he succeeded in combining his language skills with his passion for gardening in a novel career as a garden writer and lecturer. He has notably been editor-in-chief of HousePlant Magazine, Fleurs, Plantes et Jardins, À Fleur de Pot and Houseplant Forum magazines and is currently the garden correspondent for Le Soleil and radio garden commentator for CKIA-FM Radio. He is a regular contributor to and horticultural consultant for Fleurs, Plantes, Jardins garden magazine and has written for many other garden publications in both the United States and Canada, including Canadian Gardening, Harrowsmith, Horticulture, Fine Gardening, Rebecca’s Garden and Organic Gardening. He also speaks frequently to horticultural groups throughout Canada and the U.S. His book credits include The Garden Lover’s Guide to Canada, Complete Guide to Houseplants, Making the Most of Shade, Perennials for Every Purpose, Annuals for Every Purpose, and Houseplants for Dummies, as well as nearly 50 other titles in English and French. He can be seen in Quebec on French-language television and was notably a regular collaborator for 7 years on the TV shows Fleurs et Jardins and Salut Bonjour Weekend. He is the President of the Garden Writers Association Foundation and the winner of the prestigious 2006 Garden Media Promoter Award offered by the Perennial Plant Association. An avid proponent of garden tourism, he has lead garden tours throughout Canada and to the gardens of over 30 countries over the last 30 years. He presently resides in Quebec City, Quebec.

1 comment on “Tips on Harvesting and Storing Potatoes

  1. How did potatoes get identified as tubers? I have heard them referred to as stem tubers, which I suppose makes sense. They are sort of like tubers on the stolons. I think of them as stoloniferous.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: