Click below to listen to my 2 min. Garden Bite radio show: Hardy hibiscus aka Rose of Sharon
Last Fall I bought, on impulse, a gorgeous hardy hibiscus labeled ‘Luna White’. It was to grow 3 feet tall. Turns out it’s actually ‘Strawberry Cheesecake’ and grows to about 5 feet tall! That’s okay, it’s gorgeous. So why do you care? Well, first it’s interesting that plants can be mislabeled. It happens. In fact, it’s kind of fun trying to figure out what it is you actually have!
The other reason is that hardy hibiscus, more commonly known as Rose of Sharon, can be planted now. As a hardy shrub, planting now, with care, will give it a great headstart next Spring!
As I mentioned on my show, during a recent motorcycle trip in Wisconsin, I came across a beautiful red Hibiscus/Rose of Sharon/Rose mallow… I think I’ve narrowed it down to this ‘Cranberry Crush’. This beauty grows to about 4 feet tall and the 7 to 8 inch wide red blooms.
Perennial Hibiscus should NOT be cut back in the Fall. Rather, cut it back to 4-6″ from the ground in the spring. Since this plant doesn’t leaf out until late, any time in spring before the new growth appears is fine. The stems are quite woody, so a saw or strong pair of loppers is necessary to cut through the thick stems.
If you want to get really bushy and full Hibiscus plants, when the shoots start to come out of the ground and are about 6-10 inches tall, pinch them in half. The pinch should be made just above a set of leaves, this will improve branching. Improved branching will yield more flowers.
If you are really dedicated, you can pinch them back 2 or 3 times before the 4th of July. Each time you pinch, take no more than half of the stem and pinch just above a set of leaves.