Plant care guide
Why Is My Hoya Dropping Leaves? Wet Roots, Cold or Thirst
Updated
Why is my Hoya dropping leaves?
A hoya drops leaves mainly when its mix is wrong in either direction. Waterlogged, poorly drained compost is the most common cause, and the RHS also names cold in winter. NC State Extension says soil that is too wet or too dry can cause the leaves to drop. Cold water, drafts and mealybugs are the next things to check.
What to do first
Feel the mix and lift the pot. If it is wet, stop watering, empty the saucer and check the roots and the vine base. If it is bone dry and the leaves are soft or wrinkled, water thoroughly. Move the plant away from cold glass and drafts, and use room-temperature water.
A hoya losing its thick, waxy leaves is a shock, because the plant looks so robust. The cause is usually in the pot or in the air around it. Check both before changing anything.
The RHS hoya growing guide lists dropping leaves, blackening leaves and dieback as problems. It puts them down to poorly drained or waterlogged compost, or being too cool in winter. NC State Extension’s Hoya carnosa profile adds that soil that is too wet or too dry can cause the leaves to drop.
Read the leaves before they fall
| Leaves before dropping | Mix | Most likely cause |
|---|---|---|
| Yellow, soft or blackening, vine base dark | Wet days after watering | Waterlogged mix, root rot |
| Wrinkled, soft, limp but green | Bone dry, pot light | Too dry for too long |
| Wrinkled or limp | Wet | Damaged roots that cannot take up water |
| Green or blackening, after a cold night | Any | Cold or drafts |
| Sticky, with white cottony clusters at the leaf joints | Any | Mealybugs |
Waterlogged mix
Clemson Extension’s hoya factsheet calls overwatering the most common issue and root rot the biggest threat to a hoya’s health. It adds that a pot too large for the root ball makes it hard for the mix to dry.
Iowa State University Extension’s hoya guide explains why. Many hoyas grow on tree branches in nature, so their roots need air. It says overwatering in a poorly drained mix is the quickest path to root decline.
University of Maryland Extension’s root rot page says one root rot can turn lower stems black, brown or mushy, which leads to lower leaf yellowing and drop. If leaves yellowed first, see our hoya yellow leaves guide. If roots are soft and dark, go to the hoya root rot guide.
Too dry
NC State says too dry soil drops leaves as well. Iowa State says wrinkled or soft leaves may mean underwatering. But if the mix is wet and leaves still look stressed, the roots may be damaged. Our hoya wrinkled leaves guide separates the two.
Cold, drafts and cold water
Iowa State says hoyas do best at 18–27 °C (65–80 °F) and do not tolerate temperatures below 13 °C (55 °F). It warns against cool spots near windows in winter. The RHS gives a minimum night temperature of 10 °C (50 °F) for Hoya carnosa. It advises keeping hoyas away from radiators, heaters and cold draughts.
NC State also warns that cold water can shock this plant, and recommends water at room temperature.
A move, and bud drop
Iowa State and the RHS both warn that moving a hoya in bud, or changing its light, can make it drop its buds. If you are losing flower buds rather than leaves, see our hoya blooming guide.
Pests
Iowa State says mealybugs are among the most common hoya pests, often hiding in leaf axils and along stems. Spider mites can appear in very dry indoor air and cause stippling. The RHS also lists sap-sucking mealybugs.
What to do
- Check the mix. Clemson suggests learning the weight of the pot when dry and wet.
- If the mix is wet, stop watering and empty the saucer. Slide the plant out and look at the roots. The RHS says plants with root rot often won’t recover, so take cuttings from healthy vines straight away.
- If the mix is dry, water thoroughly until the whole root zone is wet, then let it dry almost completely before the next watering, as Iowa State advises.
- Move it somewhere warmer and away from cold glass, heaters and drafts.
- Use room-temperature water.
- Repot only if needed. Iowa State says to go up one pot size at most, into an airy mix such as potting soil with orchid bark and perlite.
- Inspect leaf joints for mealybugs and isolate an infested plant.
Judge recovery by new leaves on the vine tips. Do not cut off the flower spurs (peduncles) while you tidy the plant. Iowa State notes that hoyas rebloom from them. More pages are on the hoya hub.
References
How this guide was put together: RHS, NC State Extension, Iowa State University Extension, Clemson Cooperative Extension and University of Maryland Extension guidance.