Updated for 2022.
Are we there yet? After our long, cold April, it looks like weather in Minnesota is finally warming up. Many folks in northern Minnesota still have snow or ice, but the warm temps in the next few days should make short work of that.
What to do in the garden in May? The better question is what not to do as May is likely the northern gardener’s busiest month. Cleaning up, feeding the soil, planting, weeding and plant shopping are among the tasks to keep gardeners busy in May.
Here’s a short list of garden chores for May:
Clean beds as needed. During this month, many pollinators will vacate their winter homes in your garden debris and it’s safe to clean up the bed. This means cutting down the spent bloom stalks and pulling weeds. Some gardeners use the “chop and drop” system rather than compost or remove debris.
Turn your compost pile. Once it warms up, you can turn your compost pile and remove any fully finished compost to spread on your garden beds. Turning compost brings air into the pile and speeds up the composting process. Lee Reich, an occasional contributor to Northern Gardener, has a great compost system. He even composts his underwear!
Feed the soil. As soil warms up, it is a good time to spread compost or composted manure, especially on vegetable beds to feed the soil and get your seedlings off to a good start. Be careful about where you get your compost, however, as Minnesota is seeing an increase in the number of jumping worms present in the state. Most of the reports so far have been in the Twin Cities. Compost made on your own property is the best.
Harden off your seedlings. If you have seedlings in the house, now is the time to start hardening them off and getting them ready to plant outdoors. Vegetables such as lettuce and other greens, radishes, peas and other cool season crops can be planted out. Keep warm season crops under lights or in a greenhouse until the nighttime temps are reliably in the 50s—hopefully that will happen in the next couple of weeks, though soil will still be cool.
Set up cages and trellises. It’s a lot easier to put a cage or plant hoop around a small peony or other floppy perennial now rather than later. Trellises, too, can come out of storage and get set up for vines to grow up as the season progresses.
Plant some vegetables. Early May is a good time to plant potatoes, beets and other root crops. You could also seed some lettuce amid the ones you started indoors for a continuous crop. Hold off until the end of the month or early June to plant tomatoes, peppers, eggplant and other warm season crops.
Pick asparagus; wait for rhubarb. Perennial vegetables are the best—they just keep coming. If you are one of the lucky folks with an asparagus patch, begin harvesting when the spears are 7 to 9 inches tall and continue until the spears start to get wider than a half inch or so in diameter. Then it’s time to let the plant grow its ferns and store up energy for next year. Rhubarb generally is not ready to harvest until mid to late May. Wait until the stalks are at least a foot long, then pull and twist them to harvest.
Buy annuals. Mother’s Day weekend is traditionally the time Minnesotans buy annuals for containers and beds. We can still get a frost after Mother’s Day (and this year, it’s early), so be prepared to throw a sheet over the flowers or bring them in the house. Check out the deals at some of our Discount Partners.
Container time! This hardly seems like a “chore” but May is the time to start designing and putting out your containers. Of course, you can buy beautiful containers ready-made from garden centers, or you can buy annuals and design your own. Have fun with containers! Pick a bold pot to be on-trend for this year, then fill it with a single striking plant or a collection of thrillers, fillers and spillers.
This first weekend in May looks like a winner in terms of weather, so it’s a great time to get out and enjoy your garden.