If your hoyas have already bloomed, just wait until the start of the next growing season to take your cuttings.
Hoyas have sticky sap inside the stems that could irritate your skin. Wear gardening gloves to protect yourself while you work. You may be able to propagate hoya just from a leaf cutting. Rather than trimming off a full stem, snip off a leaf and 1 1⁄2 inches (3. 8 cm) of the petiole, which is the part of the leaf that connects to the stem.
Leave the rest of the leaves on the hoya stem so they can absorb sunlight and help your plant develop healthy roots.
Rooting hormone stimulates the hoya stem to develop roots from the nodes rather than regrowing leaves or other branches.
Once the roots have formed, fill a 3–4 in (7. 6–10. 2 cm) pot with orchid potting mix and transplant the cutting into it. Be sure to completely cover the roots with the potting mix. Hoya roots are a little more sensitive to being moved and transplanted when you propagate them in water, so try the soil method if your hoya doesn’t survive being transplanted.
If you’re growing hoya from a leaf cutting, plant it in the soil the same way so the base of the leaf is just above the soil’s surface.
Avoid letting the potting mix get soggy or waterlogged since it will prevent healthy roots from developing.
With a plastic bag over the pot, the moisture from the potting mix will stay trapped inside and promote faster growth. Hoyas grow best in 30–40% humidity. Try using a humidity meter to track the levels inside your pot.
If you don’t have easy access to a window, use a grow light instead to help your hoya thrive. Keep the grow light about 20 inches (51 cm) away from your cuttings and run it for about 12–16 hours since it isn’t as intense as direct sunlight. [12] X Research source
If you don’t see any roots, keep the plastic bag on the pot for another 2–3 weeks before checking again. If roots still don’t form, then it may be easier to try planting a different cutting.
If you leave hoyas in direct light for too long, the foliage will start to burn and get damaged.
If the leaves start turning yellow, it could be a sign that you’re overwatering your hoyas.
Alternatively, fertilize your hoyas once a week. Just use ¼ of the recommended amount on the package. If you want to help your hoyas start blooming, use a high-phosphorus mix every 2 weeks in late spring through late summer instead.
Varieties like hoya odorata and hoya kerrii labeled “sweetheart hoya” won’t develop vines, so you don’t need to trellis them. [17] X Trustworthy Source Penn State Extension Educational organization dedicated to delivering science-based information to people, businesses, and communities Go to source
If the mealybugs return or horticultural soap doesn’t work, use a systemic insecticide that’s a little stronger instead.
Hoyas don’t mind if their roots fit tightly in the pot and will still continue to bloom, so only repot them if you notice that they aren’t growing.
