Gardening with Laurie: Getting ready for frost

By Laurie Brown
Reader Columnist

Horrid though it seems, frost will be here soon. The average first frost date in Sandpoint is Sept. 15, so we could be less than two weeks away. Colder areas, like up Gold Creek, will have frost even sooner. While it always seems to come too soon, this year it’s especially painful because we’ve had such weird weather this summer. 

Some crops will breeze through the first few frosts; cabbage, broccoli, cauliflower, Brussels sprouts, carrots, turnips, Swiss chard and Asian greens will all survive and some, like parsnips and Brussels sprouts, will actually get sweeter.  But what about the warm-weather crops? 

For a bed of plants like bush beans, floating row cover will protect against a light frost. If frost does get the bean plants, pick all the beans and cook them promptly. 

For bushy plants like peppers or small tomato plants, use cardboard boxes or wicker baskets to cover them at night. Remove in morning. 

If frost does get to your plants, try hosing them down before the sun hits them in the morning. If the plant is not badly damaged, this may save them for a little while longer. These last minute saves are particular useful given the way our autumns tend to give us a night or two of frost, and then warm back up again for a week or two. 

Now is the time to urge the tomatoes to ripen. The way to do this is root pruning. Take a spade and insert the blade full depth into the ground all the way around the tomato plants stem, about a foot away in all directions. Also, take all the new flowers off the plants from here on out. These steps will speed ripening of existing fruit. When frost is predicted, go out and either pull out the tomato plant and hang it upside down in a sheltered spot, unripe tomatoes and all — they’ll ripen on the plant — or pick all the tomatoes, in whatever stage of ripeness they are, and bring them in. Lay them one layer deep on newspapers or wrap them individually in newspaper and they will ripen slowly (remember to check them frequently!). Green tomatoes must be picked before frost touches them or they will rot instead of ripening.

If the tomatoes ripen faster than you can eat them, the best way to deal with them is to simply rinse them off, throw them into plastic bags and freeze them. Even tomatoes with bad spots can be preserved this way; just cut the bad bits off and throw the good parts in. By doing this, you can wait until you have a large amount of ripe tomatoes before you cook them down into sauce, which saves time and effort over doing multiple small batches. This also allows you to deal with making the tomato sauce on your own schedule rather than whenever a few tomatoes ripen — making a large pot of spaghetti sauce is a nice project for a winter day. The bonus part of freezing the tomatoes before processing them is that as they thaw, you can give them a squeeze and the innards will squirt right out of the skins with no effort!

This is a good time to find the microclimates in your garden: What areas get frosted first? What areas seem untouched? You may find spots where frost doesn’t reach until late in the season. These spots are frequently around buildings, large rocks, water features, by trees and on inclines — but not at the bottom of the incline. This is valuable information; these are the spots to plant frost sensitive plants or those you are “pushing the zone” with.