Rose of Sharon (Hibiscus syriacus), for many, is an easy to grow shrub that they would consider more of a weed than a plant!
For others however, they can have some problems, so let’s go over Rose of Sharon’s needs and how to best overwinter them if you’re in a very cold northern climate.
Rose of Sharon Basic Growing Needs:
Do well in Zones 10 to 5 which means they can tolerate winter cold from 40Â° F (4.4 Â° C) down to -20Â° F (-29Â° C)
Prefers full sun and heat, and tolerates some drought. If in a very hot area, afternoon shade may be a benefit
Likes moist, well-drained soil with regular water but not too much. They don’t like soggy or wet soil, and can have yellowing leaves and leaf drop if soil is a heavy clay or doesn’t drain well. In that case, allow plants to dry out a bit in between waterings
Try not to fertilize after July. You don’t want to encourage lots of soft growth that will be harmed by frost in the fall
Where winters drop to -10Â° F (-23Â° C) or colder, protect plants with winter mulch
A deciduous shrub (but can be an evergreen in warmer climates)
Grows to 12 feet (3.5 m) tall with a spread of 3 to 6 feet (1 to 1.8 m)
Flowers all summer long into early fall (until frost) in shades of white, pink, soft red, mauve, and violet blue
Flowers attract hummingbirds
Leafs out in the spring much later than most other deciduous shrubs which can cause a false alarm for gardeners who think their plants may have died. Patience in this case is the best remedy
Foliage drops in the fall without coloring
Prune to shape in the first two years of growth, trimming lightly thereafter to maintain a compact form. If the plant needs a heavy pruning, the best time to do so is in late winter, early spring. Light shaping or pruning can be done at any time
Overwintering Rose of Sharon:
Rose of Sharon will do better if left in the ground to overwinter
One of the biggest tips is placement! Make sure your plants are out of direct heavy winds
Mulch heavily with leaves in fall and use burlap around the bush in the winter to help insulate it. You may not want to mulch until your ground is frozen so as not to attract voles or mice to the mulch. But if they have not been a problem, you can go ahead and mulch after the leaves have fallen from the trees.
Reliable snow cover all winter helps insulate them from the cold
Don’t prune it until spring….that way you can cut off any winter die back that you might get. They also bloom better after a good pruning in the spring as they bloom on new wood
Have good week!