In this climate, mums are generally considered annuals. Whether you pop them into a container or basket, or set them on your porch, they will provide immediate color and bloom for a long period. Our plants are so full of bloom, that they do require a lot of water, so be sure to keep them evenly moist. They don’t like to dry out or sit in water.
If you want to try to establish mums as perennials, plant them as soon as possible in a sunny, well-drained location. They don’t do well in our heavy clay soils, so incorporate peat or compost when planting them. A protected spot away from cold, drying winter winds also helps survival. Plant them deeper than they are growing in our pots. Remember, to survive, they have to develop roots at or above the first set of branches before the ground freezes.
Do not cut back dead plants until next spring. Research at Iowa State University shows leaving stems and foliage results in better winter survival. Apply loose winter mulch after the ground freezes. Straw, shredded bark, pine boughs and even snow are good winter mulches. Carefully remove in the late spring. And remember mums are heavy feeders, so apply all-purpose fertilizer (per package instructions) from late spring until mid July.