How to

16 March 2017

Cold-Hardy Crops - Powering Through the Chill

Img: Flickr 
For a gardening-novice like me, the general rule seems to be that crops need sunlight and water to grow, right? However my eyes have been opened to the hardy crops that can withstand colder temperatures, and how they do it with the use of sugars, proteins, and protection.

The general science behind the hardiest vegetables is that they contain tolerance proteins and sugars, which double up as anti-freeze and protection.  These proteins and sugars prevent the initiation of ice crystals which have the potential to damage the crops.  See the table below, courtesy of vegetable gardening expert Mother of a Hubbard:


Cold-hardy crops won’t always reach harvest successfully, but it’s not always due to the cold.  Ruin could be due to desiccation, in which the crops simply dry out, due to the water having moved out of cells, combined with low humidity and winds. When ruined, cold-hardy plants dehydrate and appear brown, whereas warm-season crops turn mushy and soft, as they don’t contain the preventative sugar and protein adaptations.

Carrots and parsnips are similar in what they can withstand, both containing similar sugars which fight off the freeze. Green carrot tops can withstand lows of -8°C, with the roots capable of withstanding even lower temperatures.  For both carrots and parsnips, it is advised to cover the crops for ultimate protection in the coldest periods, but generally, the Brit-favourites are pretty hardy in the winter chill.

Leeks and garlic tops are impressively resilient to hard freezes; leeks deemed the ‘champions of winter gardens’ by Mother of a Hubbard. They take well to shorter winter days, and the darker, blue-green varieties are able to withstand temperatures of -18°C.

When it comes to cabbages, some varieties thrive whilst others spoil in hard freezes. Flavour is sometimes improved, and the cold scares off insects and pest populations. However due to the delicate nature of the leaves, it’s highly advised that cabbages are covered to be most protected and have the highest chance of success.

So, who would’ve thought it? Those are just some details on the vegetables that power through the colder months; check out Mother of a Hubbard, Seedsavers and year-round harvesting books for further information.


Laura Sewell

An aspiring journalist, Laura is our content writer intern.  Pop-punk gig-goer and drag queen enthusiast, Laura is working her way into the industry, with an English A -Level and love of writing about anything and everything in tow.