Azaleas can be propagated from seed, cuttings, layers, grafts, or tissue culture. The easiest method is to propagate from cuttings.
Steps for propagating azaleas from cuttings
Take cuttings: In early summer for indoor azaleas, or July to mid-September for garden azaleas, take semi-ripe cuttings from new growth. Softer wood roots more easily, but is more susceptible to fungus.
2. Prepare the cuttings: Remove any flower buds, and cut the leaves in half to reduce their surface area. You can also make a wound on each side of the cutting, about 1/2″ to 1″ long, to remove a sliver of green bark.
3. Apply rooting hormone: Dip the cutting in a rooting hormone that contains indolebutyric acid (IBA).
4. Plant the cuttings: Place the cutting in a pot of gritty ericaceous compost, or a sterile media mix of sphagnum moss and perlite or vermiculite.
5. Cover and water: Cover the pot with a plastic bag or propagator lid. Water gently and thoroughly, and maintain moist but not wet soil.
6. Monitor: Check the cuttings regularly for signs of growth.
You can also propagate azaleas by layering, grafting, or tissue culture.