Don’t Rush Spring! Your Yard & Gardens will Thank You.

I’m sitting in my cozy chair, watching a normal mid-March blizzard, and catch myself wishing: “When this snow melts, I’ll start doing some yardwork.” But I know it’s much too early to be doing any kind of cleanup, lawn work, or planting, but I have the bug to do something! Here are some things you can do, and more that you shouldn’t do this early in the season.

Collecting sap and making syrup is an excellent activity for gardeners at this time of year. Right now, the soil is frozen. Some of it will thaw soon, but it will refreeze if there are sub-freezing overnight temperatures. These above and below freezing temperatures are the conditions when the maple sap is running.

   Soil microbes don’t wake up until the soil temperature is at least 40 degrees in the top few inches, and you should leave it alone for a while. Soil at these temperatures is usually wet and very soft, and working it will cause compaction and create a mess that is difficult to correct.

   Lawns, especially, should be left alone until the soil has dried and is warmer. If there are piles of leaves that are in danger of smothering the grass, they should be blown off, if possible. Rakes can really damage grass if the soil is too cold and wet. Using mowers or other equipment when the soil is soggy will cause compaction, which is the number 1 cause of weeds. Any remaining leaves on the grass can be cleaned up with a mulching mower when the soil is warm and dry.

   Corn gluten meal, an organic weed and feed, works best when applied at the rate of 20 lbs./1000 sq ft when the soil temperatures are 50 degrees. You can look up your soil temperature in the link above or watch for when the forsythia is blooming.

   Another lawn task that can be carried out at low temps is overseeding. 2 – 3 lbs. of seed / 1000 sq ft applied at 40 degrees soil temps will lay dormant until the soil is warm enough to germinate grass seed, usually around 55 – 65 degrees. Do not apply corn gluten meal and seed at the same time, as the corn gluten meal is a pre-emergent and will keep the seed from germinating. You can do one or the other, but not both.

   Veggie gardens should be left alone until planting time. At that time, you can simply pull back leaves and mulch to seed or transplant. Replace the leaves and mulch after planting, and water thoroughly. Many online resources give guidance for working in the garden based on the average date of the last frost. My favorite resource for this information is “The All New Square Foot Gardening” by Mel Bartholomew. There are charts and schedules for indoor seed starting, outdoors direct sowing, transplant dates, and even a schedule for planting crops for fall harvest.

Brassicas (kale, cabbage, broccoli, cauliflower) can tolerate soil temperatures of low 50s to high 40s, but they will grow slowly, and damp, cold conditions are what fungal diseases like. These plants prefer soil temperatures in the 60s and 70s.

GreenCast has a helpful link to find the soil temperature in your area. Another good resource for timing on seed starts, direct sowing, and transplants is the Survival Garden Seed website. These schedules remind me to keep my spring fever in check and also let me know if it’s too late when I get busy in the spring, and my garden planting has been put on the back burner.

   There are different methods for dealing with spring temperature swings in the veggie garden. The easiest practice is mulching around plants and between rows. Mulch provides an insulating layer on the soil, keeps soil temperatures stable, while conserving moisture, encouraging beneficial soil microbes, and suppressing weeds.

   You can also create heat-trapping structures like hoop houses of clear plastic over the beds or individual plants. Every layer you place between plants and the weather is like moving your garden 100 miles south. There are many online resources for this kind of season extension. The Seed Savers Exchange is a good resource on the basics. Many veggies are delicate and need a lot of protection from the harsh MN climate. Some plants are a little more durable.

   Native perennial gardens are tough and thrive on neglect. Their pollinator friends definitely prefer less maintenance, especially when it comes to cleanups. Current guidelines of waiting for daytime temperatures to be in the 50s or 60s have been found to fall short of protecting overwintering insects. Recent studies show that the best management practice is to do no cleanups, especially in native plant beds. The plants and pollinators definitely prefer a rich debris layer, like would happen in nature. I wait until June before removing any of last year’s stems to protect stem nesting insects. Leaving the stems in the garden so that they break down in place mimics the natural environment.

   It seems that it’s human nature for people to start too early in the garden and yard, especially with clean-ups. My advice is to do your spring cleaning inside your house and let nature take care of the outside. Your yard and pollinators will thank you for the lack of effort.

• Bob Dahm