I was recently asked about rooting tropical hibiscus. There are many variations on the same basic idea, here is mine.
(This works for most plant propagation, not just Tropical Hibiscus)
Start with fresh stem cuttings, preferably about the diameter of a pencil. Cut the stem with clean sterilized shears or knife.
Be aware that many plants freshlt bought from nurseries have been treated with growth retarding hormones to temporarily increase blooming. That treatment will also make it hard to propagate cuttings until the plant outgrows the hormone treatment over several months.
Sterilizing can be done with alcohol, hydrogen peroxide, or simply use alcohol-based hand sanitizer.
My preferred rooting container is a clear milk jug or 2-liter soda bottle. Fill with Perlite, poke a couple of holes 2″ from the bottom. Add water, making sure the new dry Perlite is thoroughly saturated with water before inserting cuttings.
The jug with drain hole keeps the cuttings damp without open water for mosquitos to breed in. The clear plastic makes it easy to see new roots forming.
Cuttings are usually dipped in rooting hormone, but some varieties don’t really need it.
Clipping the remaining leaves makes it easy to identify new foliage growth. Leaving too many leaves will dry the cutting out before it can root.
As long as the outside temp is over 80F, I just put my rooting jugs in shade on our concrete patio. A heating pad is used in winter, while plants are in a greenhouse.
When ready, instead of pulling the rooted cuttings out, run a gentle stream of water into the jug to wash out the Perlite and gently float the cuttings out. Rooting Hibiscus in only water can lead to fragile “water roots”.
This method has worked for me over 4 decades and several 1,000s of Hibiscus.
