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Not Too Late to Put Mulch Down

This fall has certainly been anything but normal, with temperatures indicative of January, and early snow.  If you are wondering what else can be done in your garden before the snow sets in for the season, remember that you still have time to mulch.  Mulch is a standard form of winter protection for many shallow-rooted plants, and young or tender perennials. While in summer, it is effective in retaining soil moisture, preventing erosion, and controlling weeds, in winter it acts as insulation for the soil and plant roots.

Mulch can consist of shredded leaves, pine needles, hay, or straw. Apply 6-8 inches of mulch for that extra insulation.  Keep in mind this may encourage mice or other rodents to harbor and feed on the stems of the plant, so wait until the ground begins to freeze to discourage this habitation. The general rule of thumb is to mulch prior to the first heavy snow, but that can present a problem here in Minnesota. We have all seen heavy snows early in the season come before the ground has frozen only to melt away and leave barren ground. 

Failure to mulch landscape plants and evergreen shrubs in cold climates may lead to winter root injury.  Alternate thawing and freezing of un-mulched soil, as temperatures warm during the day and drop at night, may cause “frost heaving” in the spring. Do not remove the mulch too early; as it is important for the soil to gradually warm. In spring, monitor the soil temperatures and growth of the plants; simply remove once the plants begin to show signs of growth.

If you haven’t already done so, apply a protective layer of mulch to your strawberries. Clean, weed-free straw is the preferred mulch material.  This can be oats, wheat, or even soybean straw; cornstalks are another possibility but may be a bit more difficult to work with. Simply apply 4-6 inches of material. Using leaves as mulch is not recommended because they may mat and create areas where moisture and air is trapped and create ice. 

Do your plants a favor by giving them the needed protective mulch layer this fall. As a reminder, don’t forget to monitor them in the spring and remove it at the appropriate time. Too early could lead to heaving or damaging freezing temperatures, too late could lead to mold or leggy, weak growth.