The bright red blooms of the swamp hibiscus (Hibiscus coccineus), also called scarlet rose mallow or Texas star, attract attention in the garden. Individual blooms reach diameters of 6 to 8 inches and bear five-pointed petals that reflect the shape of the plant's palmate, lobed leaves. Hardy in U.S. Department of Agriculture plant hardiness zones 7 through 11, swamp hibiscus needs regular pruning throughout the year to keep its 7-foot-tall stems from become leggy and unattractive.
Pour 1 part bleach and 9 parts water in a bowl. Submerge the blades of the pruning shears in the solution to sterilize their surfaces. Leave the blades to soak for five minutes.
Cut each stem at a 45-degree angle with the pruning shears, 2 inches above ground level. Position the cut 1/4 inch above a bud or outward-facing, living side shoot. Trim back any broken or cracked stems, cutting 1/4 inch above a lateral shoot or growth node at least 1 inch below the broken portion of stem. Do this in spring, when new growth starts.
Remove the tip from each of the swamp hibiscus' stems in late spring, once the new growth reaches 18 to 24 inches tall. Cut through each stem with pruning shears, 1/4 inch above the second set of leaves below its terminal end. This helps encourage branching.
Prune individual flowers off the plant once their color fades and the petals begin to drop. Slice through the flower stem, 1/4 inch above its base.
Cut the entire swamp hibiscus plant back after it finishes blooming to maintain a bushy, pleasing shape. Cut off the top 25 percent of each stem, making the cut 1/2 inch above an outward facing lateral branch, set of leaves or bud.