Plant rose of Sharon (Hibiscus syriacus) if you want a hedge shrub that flowers late in summer when not much else is blooming. Hardy rose of Sharon is drought- and pest-resistant and will grow in most soil types. Plant noninvasive cultivars like Aphrodite, Diana and Helene if you want fewer seedlings volunteering in the landscape. If you've inherited a rose of Sharon that seeds profusely, there are a number of ways to keep seedlings from invading your lawn.
Pull the smallest seedlings by hand, choosing a day with light rain or the day after heavy rain. If the soil is loosened and wet, many of the seedlings will come right up.
Dig out larger rose of Sharon seedlings with a spade. Point the tip of the spade straight down, right next to the stem, and push. Wiggle it a little. Repeat on the opposite side of the stem and pry it up.
Target spray seedlings with glyphosphate foliar herbicide if there are too many to pull or dig by hand. Squirt it on the leaves and they will die.
Mow the area under and near the rose of Sharon tree that's producing all the seedlings. Regular, repeated mowing will clip off the seedlings and starve their underground roots.
Clip off flowers when they fade to prevent seed pods from forming. The rose of Sharon will put its energy into producing more flowers instead of seeds that become seedlings.
If you choose not to get rid of rose of Sharon seedlings, you can let them grow into a thick hedge and control with pruning.
Rose of Sharon seedlings can spread along the foundation of a house and crack it with their roots. Target with glyphosphate herbicide as soon as you see them.