Your Hoya likes to dry almost all the way down between waterings. However, extended periods of dryness will cause the roots to start to shrivel and die back. This means that once the plant is thoroughly watered, it cannot take up the moisture properly. Always check the soil before watering. Water thoroughly and evenly around the pot until you see water flow out of the drainage hole. Be sure to discard any excess water after a few minutes.
If you find the soil to be bone, your Hoya could use a deep soak.
- Fill a sink or tub with 2″-4″ of water, depending on the size of your plant.
- Set the plant in the water without the saucer to allow it to soak the water from the bottom. Let the plant sit in the water for at least 30 minutes.
- After the 30 minutes is up, feel the top of the soil to see if it has soaked up enough water. If it needs a little more time, let it sit for an additional 15-30 minutes, or water slightly from the top of the soil.
- Drain the sink and let the plant rest and allow the water to trickle from the bottom.
- Place the plant back on the saucer making sure there is no standing water.
A less common cause of leaf wrinkling is overwatering. While overwatering is usually signaled by yellow leaves, leaf curl, and leaf drop, wrinkled leaves can also occur. This is why it is important to check the soil moisture to see what might be the culprit.
While most hoyas can do well with average humidity, low humidity can cause wrinkled dry leaves. Try misting regularly, adding a pebble tray, or placing a humidifier nearby.