Click below to listen to my 2 min. Garden Bite radio show: Warming up your soil
…for an early start to planting! With the Polar vortex having made a couple of appearances so far this year, it’s hard to imagine warmth, but today I’m going to talk about ways to warm up your soil faster in the spring. First let’s talk climate zone, essentially the Upper Midwest is divided in zones, from 3b to 5a with 20 to 40 below zero lows. And some southern portions could squeak by a zone 5. Click on the climate zone map for you
Warm up your garden soil by securing black plastic on top of your bed several weeks before the last frost date. Generally that’s May 15th for zone 4 and May 29th for zone 3. Those dates are not written in stone especially due to warmer temperatures. Remember, these are AVERAGES, if we get warmer or colder temperatures into Spring, that will make a difference. Here’s more information from Colorado State University.
Tomato and pepper plants are usually planted 2 weeks AFTER the frost date because they love warmer soil. By using black plastic, you can give them a headstart. Take your soils temperature. It should be at least 55 degrees for tomatoes and other heat-loving plants.
REMOVE the black plastic once the soil’s warmed up. I don’t like using plastic for any reason other than warming up the soil. The benefit of fewer weeds is not worth the loss of rain water, oxygen and the ants that like to live underneath.
Another way to have warmer soil is to build a raised bed.