May in the Upper Midwest
From May 4 in Grand Rapids to May 11 in Green Bay, and as late as May 25 in International Falls, this is the month of last frosts in upper Midwest states. It’s time to enjoy spring blooms and get down to the real work of making sure your garden will thrive throughout the growing season. Upper Midwest gardening in May results in big payoffs for the following months.
May Gardening To-Do List
May gardening tasks in the upper Midwest include a wide range of activities that can be roughly broken down by week. Of course, there is some variation depending on the exact location, but, generally, in the first week of May you can:
Aerate the lawnPrepare the soil in bedsHarden off transplants by putting them outdoors during the dayStart seeds for warm weather plantsSow seeds outdoors for cool weather plantsClean up perennials
During week two you can:
Transplant frost tolerant vegetables like broccoli, cauliflower, onions, and Brussels sproutsClean up perennialsFertilize perennials and rosesMow the lawn if necessary
For the third week of May:
Directly sow seeds for corn, beans, watermelon, pumpkin, and winter squashRemove spent flowers from spring bulbs, but leave foliage in placePlant strawberriesPlant annuals
In week four, you can:
Transplant warm season veggiesPlant annualsPrune any flowering trees or shrubs that have finished bloomingFertilize the lawn
Throughout May it is important to check plants for signs of pests or diseases. Catching them early will help you better control any infestations or infections.
