Inaddition to the hormone you need to mist the cuttings & keep the soil moist..... Also Try bottom heat.

I see that you are in zone 7, and quite a bit cooler than we are here. However, you can still root hibiscus.

Timing is important. I wait until it is warm outside. Hot is almost better, but it is harder to keep cuttings damp. Nevertheless.....

Make cuttings about 12" long, from the tip of the limb. Be sure you make your cut about 1/4" below a node. Your cutting may be longer than 12"- that is o.k. Remove all the leaves, except the top 3. If they are large leaves, cut the leaves remaining on the cutting in half. Dip the cut end into rooting hormone, and tap off the excess. It is better to use too little than it is to use too much.

Make a hole in damp medium consisting of peat/perlite in equal parts. Do be sure your medium is damp throughout. If it is damp on top, but not where the dipped end is, you are going to have a hard time rooting anything. Place the cutting in the hole and pull the medium up snugly around the cutting.

You can place a plastic ice bag over the pot-cutting and all. Or, you can cut the bottom from a 3 litre soda bottle and place it over the pot. Whatever you use, you need to preserve the moisture around your cutting. Keep it out of the sun, too! The sun is death to the cutting.

If you have a drip line around your house, and a place in that drip line is shady all day, that is a perfect place to put your cutting. You don't need any covering over the pot, if you can set it in the drip line. Condensation drips from the roof and keeps the cuttings moist. A shady drip line is a wonderful thing.

Then you just wait. I should tell you that for us, May is the perfect time to do Hibiscus cuttings. The night temps stay at or above 70 degrees then, and that is necessary to root the cuttings.

Good Luck!

Janie

I did hibiscus cuttings last year using the method Janie gives above. I had moderate success. I didn't bother to sterilize anything so I had to learn the hard way that dirty tools will cause more failure than anything else. Be sure to clean all your tools with a 1:10 ratio of bleach:water. It really does help.