Snow vs. Strawberries

Last week we learned about cold weather. This week we get to learn about how snow affects crops! Surprisingly, snow is a good thing (for strawberries at least) when the temperatures drop. Strawberries can be damaged when temperatures drop below 20 degrees. Snow is 32 degrees which, for dormant strawberry plants, is nothing to be worried about. They will be just fine at that temperature. When there is a blanket of snow overtop of them stuck at the 32 degree mark, the 14 degree overnight temperatures is nothing to worry about.

In the late winter/early spring when strawberry blossoms are just starting to appear, cold is a much greater threat. Blossoms can be hurt by frost damage which can be a threat at any temperature even close to 32. Because I know you’re dying to know, here’s how it happens! Overnight, dew forms inside of the blossoms. Not a big deal, plants love water. Where it becomes a big deal is if the dew freezes; aka frost. The water droplets inside of the blossom expand, destroying the inner parts of the blossom which just so happens to be the baby strawberry… Blossoms with frost damage produce less, disfigured, or no strawberries at all. The good news is that if a bunch of blossoms are lost during a frost event, the strawberries will grow more over the course of the season, and you still might get a crop later. Unfortunately, that’s still a lot of money for a grower to lose.

It may seem counterproductive, but some growers actually use overhead sprinkler irrigation to freeze their strawberries solid in the event of a heavy frost! The idea is that if a thick layer of water is put on the blossoms, no small water droplets can penetrate and sit inside of the flowers. Then when it freezes, it forms a protective shell over the blossoms, preventing any frost damage from getting inside! I’m sure the first person who tried that got some funny looks… At least until he/she was the only one with strawberries that season!

Leafy greens and other winter crops are not so durable when it comes to the snow. If you have any spinach or bok choi like we do, cover them up! They don’t like freezing temperatures of any kind. When snow is in the forecast, be extra sure to give some support underneath your row covers. The weight of the snow on top of the covers will smoosh your poor plants dead! Most growers use hoop-houses/low tunnels. They look like mini greenhouses on top of the raised beds. Since we are just dabbling in the winter crop market, for now, we used our normal row covers that we use on our strawberries but put stakes in the plastic to raise the covers up off of the plants. If we decide to get more into winter crops, we will definitely invest in some hoop-houses.