Pocket Botanist
Check these first
- Feel the soil to see if it is soggy.
- Check the bottom of the pot for standing water.
- Gently lift the plant to see if the roots look brown or smell bad.
Likely causes
Overwatering
Most likelyHow to tell: The leaves turn yellow and the stems feel mushy near the soil line. The plant will look wilted even when the soil is wet.
What to do: Stop watering immediately and let the top 2 inches of soil dry out. If the soil is waterlogged, repot the plant into fresh, well draining potting mix.
Poor drainage
PossibleHow to tell: Water pools on the surface of the soil for a long time after watering. The roots will appear dark and slimy instead of firm and white.
What to do: Ensure your pot has drainage holes at the bottom. Use a pot that is only 1 to 2 inches wider than the root ball to prevent excess soil from holding too much water.
Find out what's wrong with your mexican petunia
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 stems are turning black and mushy at the base, the rot is advanced. It is normal for the plant to need less water during the winter months.
Stopping it coming back
Always empty the saucer after watering and use a fast draining soil mix.
Keep your mexican petunia healthy from here
Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked. Identification and a health check are free.
Questions people ask
- Can I save a plant with root rot?
- You can save it if you catch it early by trimming away the mushy roots and repotting in fresh soil. If the majority of the root system is black, it may be too late.
- How often should I check the soil?
- Check the soil every 3 to 7 days by pressing your finger into the top inch.
More problems with Mexican petunia
- Why are there tiny webs on my Mexican petunia?
- Why is my Mexican petunia not blooming?
- Why is my Mexican petunia drooping?
- Why is my Mexican petunia looking so leggy?
- Why are my Mexican petunia's leaves turning yellow?
- Why are my Mexican petunia's leaf tips turning brown?
- Why is my Mexican petunia losing its leaves?
- Why are my Mexican petunia leaves curling?
Back to the Mexican petunia guide
This article was generated with AI from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.