Pocket Botanist
Check these first
- Smell the soil for a foul odor.
- Gently lift the plant to inspect the root color.
- Check if the pot is sitting in a saucer of water.
Likely causes
Poor Drainage
Most likelyHow to tell: The soil smells sour or musty. The base of the stem may look mushy or discolored.
What to do: Remove the plant from its pot and trim away any black, mushy roots. Repot into fresh, sterile soil with excellent drainage.
Excessive Watering
Most likelyHow to tell: The plant stops growing and the foliage begins to drop. The soil stays saturated for more than 10 days.
What to do: Adjust your watering rhythm to every 5 to 10 days. Always check the soil depth before adding more water.
Find out what's wrong with your japanese cedar
The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.
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When to worry
If the roots are mostly black and slimy, the plant is likely beyond saving. Act as soon as you notice the first signs of wilting.
Stopping it coming back
Ensure your pot has large drainage holes and never leave the plant sitting in a water filled tray.
Japanese Cedar: root rot? Check yours with a photo
Every plant is a little different. Take a photo of your japanese cedar and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.
Scan with your phone's camera to get the app
Or go to pocketbotanist.app/get on your phone
Get the app · Or check it from a photo now, free
Questions people ask
- Can I save a plant with root rot?
- If you catch it early and remove the damaged roots, you have a good chance. Success depends on how much healthy root system remains.
- How often should I check the roots?
- You do not need to check them unless you see symptoms. Frequent repotting can stress the plant.
More problems with Japanese Cedar
Back to the Japanese Cedar guide
This article was generated with AI on from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.