Early autumn is an excellent time to plant flowering perennials, and the sooner they are in the ground, the better. Flowering perennials need at least three or four weeks of decent growing conditions before harsh weather sets in. This allows time for root growth so they can survive the winter. Add two inches of mulch after planting perennials, then water thoroughly. Continue to water once a week, unless rainfall is plentiful. When the soil begins to freeze in late October or November, cut foliage close to the ground and cover the plants with six or more inches of straw, leaves or other mulch. Fall is also the time to plant spring-flowering bulbs. Whether you buy locally or from a catalog, your choice of bulbs will be better now than later. Tulips can wait, but other bulbs need to be planted soon so they can develop roots for the winter. Daffodils, hyacinths, crocus, Siberian squill and other small bulbs will perform best when planted in mid- to late-September, rather than waiting until late October or November. Like flowering perennials, they need to be watered periodically unless it’s rainy. Mulch bulbs as you would flowering perennials once the soil surface freezes. Any bulbs that don’t make it into the garden this fall can only be used for forcing indoors. Deb Brown is a horticulturist with the University of Minnesota Extension Service.
