No need to throw in the trowel for the month of October, there’s plenty to do outside along with indoor garden projects. Don’t forget to dust off the rake and the snow shovel — both will be getting a work out soon. Cover Crops Hands-down the best way to improve garden soil fertility, tilth and prevent winter soil erosion is to plant fall cover crops, also known as green manures. Plant in areas where summer vegetables and ornamental annuals grew — anywhere where there’s bare soil. For fall cover crops, look for winter rye, oats, Austrian winter pea or hairy vetch seeds in garden centers or online.