One of the reasons I love living in Minnesota is that we actually have four seasons. However, I was starting to wonder if we were going to have an autumn this year. After temperatures in the 80s and 90s in the beginning of September I am ready for fall and it appears that it has finally arrived. Although we may still see a few days in the 80s, the sun will continue to be lower in the southern sky, the daylight hours will continue to shorten and finally there can be no denying that autumn is in the air. A few trees are beginning to show their colors and with the recent rainfall plus a little more ahead we should see a colorful display this year. All of that considered it is time to prepare the yard and garden for the winter ahead. I am a little weary of the yard and garden chores, but I know that everything I do this fall will go a long way to lightening the load of spring cleanup, and can also be good for the health and vigor of my lawn, trees, shrubs and perennials.
The primary fall chore is, of course, leaf raking. It can be tedious and time consuming, and something we may be inclined to skip; however I would advise you not to. Leaves left on your lawn will mat down and make the lawn more susceptible to snow mold, plus raked up leaves can be an asset to your lawn and garden if they are added to a compost pile or used to mulch your perennial beds. They can even be turned directly into a cleaned out vegetable or annual bed where they will add organic material and nutrients as they decompose. Whatever you do with the leaves be sure you do not rake them into the street where they can wash down the storm sewers and add unneeded phosphorous to our river and lakes. For that reason it is, in fact, against city ordinances to rake leaves into the street even in advance of street sweeping.
If you have young or thinned barks trees, you should wrap the bark in the fall to protect them from sunscald and hungry rabbits. New trees should be wrapped for their first two years, and thinned barked trees (which include cherry, crabapple, honey locust, linden, maple, mountain ash and plum) should be wrapped for the first five years. Be sure to remove the wrap in the spring to prevent insect or fungus damage.
Fall is the time to remove garden debris from your perennial beds. Dead plant material left over the winter may harbor insects and diseases, however any plants that remain upright you may wish to leave until spring. They will add some winter interest to your yard and in some cases provide seeds for the birds.
Mulch is an insulating material, preferably organic, that is spread over the ground and around plants. Mulch is important in both the summer and winter. In summer it prevents the run off and evaporation of soil moisture, deters the growth of weeds by shading weed seeds so that they cannot germinate, and improves the soil structure by adding organic material. It also maintains the soil temperature, which is its primary function in the winter. By keeping the soil frozen it prevents the ground heaving that can push the crowns of the perennials above the soil line where they are exposed to the elements, so ideally we should wait to mulch over our plants until after the ground has frozen. The best mulch materials are organic such as wood chips, shredded bark or wood, pine needles straw, grass clippings, compost or the leaves that you rake off your lawn.
Fall is also the time to plant spring flowering bulbs. This includes corms, rhizomes, tuberous roots and true bulbs. These hardy bulbs require a cold period to break their dormancy – our winter is their cold period. Plant these bulbs by mid-October so that they have time to grow roots before the ground freezes. The exception is tulips, which can be planted any time before the ground freezes. When planting bulbs remember that they require warmth and bright light to break dormancy in the spring, thus those planted near foundations or on the west or south are likely to bloom first. While we are anxious to see our first flowers in spring, plants that bloom too early may be damaged by spring frosts.
The cooler temperatures have invigorated me to spend some time putting my yard and garden “to bed” so that my plants and I can settle down to cocooning over the next of the four seasons in Minnesota.