Pocket Botanist
Check these first
- Inspect the spots to see if they are soft or mushy.
- Check the soil to ensure it is completely dry.
- Observe if the spots are appearing on the side facing the window.
Likely causes
Fungal Leaf Spot
PossibleHow to tell: You will see small, circular, or irregular brown or black spots on the leaves that may have a yellow halo. These often appear after periods of high humidity or overhead watering.
What to do: Trim off the affected leaves using a clean, sharp knife to stop the spread. Move your plant to a spot with better air circulation and ensure you only water the soil directly, avoiding the leaves.
Sunscald
PossibleHow to tell: These spots appear as bleached, white, or tan patches on the side of the plant facing the sun. This happens if a plant that was kept in the shade is suddenly moved into intense, direct sun.
What to do: Acclimate your plant to full sun gradually over 2 to 3 weeks. If the damage is already done, the spots will not heal, but the plant will continue to grow new, healthy leaves.
Find out what's wrong with your century plant
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.
Scan with your phone's camera to get the app
When to worry
Worry if the spots are soft, spreading rapidly, or if the base of the plant feels squishy. Small, dry, or scarred spots are usually just cosmetic and not a threat to the plant.
Stopping it coming back
Keep the foliage dry at all times and ensure your agave is planted in a very well draining, gritty soil mix. Good airflow is your best defense against fungal issues.
Keep your century plant 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
- Should I spray the spots with water?
- No, never spray water on the leaves. Agaves prefer dry foliage, and extra moisture will only encourage more fungal growth.
- Will the spots go away?
- Unfortunately, the spots are permanent scars. As the plant grows, you can eventually prune away the older, marked leaves.
More problems with Century plant
Back to the Century plant 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.