Deadheading is the horticultural term for removing faded flowers. Many natives bloom for a short period of time then stop flowering and set seed. In fact, the object of the flower is to reproduce the parent plant. Deadheading interrupts this cycle. If faded flowers are removed before they set seed, many will send out another flush of blooms to try to complete the reproductive cycle. The blooms in the second display may not be as large or as numerous as the first, but they are certainly worth the effort. Other natives that bloom over an extended period of time benefit from deadheading because it increases the number of flowers that are produced and the length of time over which they are produced. Deadheading also gives you some control over flowers that can be invasive because they self-seed. Purple Coneflower, Missouri Black-eyed Susan, Coreopsis and Garden Phlox self-seed with abandon if they aren't deadheaded.
Basically, there are two places to make deadheading cuts. With flowers that have leaves along the bloom stem, cut just above the point where you see a new shoot or bud emerging. This is usually in the axil of the set of leaves closest to the old flower. To deadhead flowering natives that don't have leaves along their flower stems, make the cut at the bottom of a flowering stem near the base of the plant.
Cutting back is a technique used to keep leggy plants more compact, to promote new foliage growth, or to coerce plants to bloom repeatedly. Sometimes you can avoid staking tall plants that are prone to flopping like tall Asters and tall Goldenrods if you cut them back by about one-half in early summer. This keeps plants shorter than normal. Still other plants like Columbine and Yarrow should be cut back to the basal foliage (leaves that grow from the crown or base of the plant) after they finish flowering. This will promote lush new foliage growth and, sometimes, another round of flowers.
Shovel dividing is a maintenance practice that keeps vigorous perennials in their allotted space. As you stroll the garden looking for weeds and spent flowers, keep an eye out for natives that are encroaching on their neighbors. When you spot plants that are getting out of hand, insert a round-point digging shovel into the plant with the back of the shovel against what you want to keep and the front of the shovel next to what you want to remove. Pull back on the shovel and pop the unwanted portion of the plant out of the ground. These portions can be discarded or shared with another native gardening enthusiast.