Most likely cause
Root rot from overwatering is the top cause of brown spots on a Fiddle Leaf Fig. These plants are notoriously sensitive to wet feet, and when soil stays soggy the roots are starved of oxygen, begin to rot, and can no longer feed the leaves, which shows up as dark brown blotches.
You can confirm it by the pattern. Rot spots are dark brown to nearly black, often start at the base or center of a leaf rather than the edge, and arrive alongside wet soil, a musty smell, and dropping leaves. Slide the plant from its pot and check the roots: healthy roots are firm and pale, while rotting roots are brown, soft, and mushy. Once you let the soil dry out and fix drainage, the spotting should stop spreading and new leaves come in clean.
Other causes
These rank below root rot but are easy to mistake for it.
- Bacterial or fungal leaf spot. Smaller spots, often with a yellow halo, that spread from leaf to leaf and appear even when the soil is not soggy.
- Underwatering. Dry, crispy tan-to-brown patches with bone-dry soil that pulls away from the pot edge; the leaves feel papery, not soft.
- Sunburn. Bleached or brown scorched patches only on the side of the plant facing a hot, direct window.
- Cold drafts. Brown blotches that appear after a chill from an AC vent, an open door, or a cold windowpane the leaves touch.
How to fix it
- Check the soil and roots. Feel the top two inches and slide the plant out to inspect the roots. Mushy brown roots mean rot.
- Ease off watering. Let the top two inches of soil dry fully before watering again, and never let the pot sit in standing water.
- Improve drainage. Use a pot with a drainage hole and a fast, chunky mix; empty any saucer after watering.
- Trim damaged leaves. Remove badly spotted or clearly infected leaves with clean, sterilized scissors to slow any spread.
- Adjust the light. Keep the plant in bright indirect light, out of harsh direct sun that can scorch the foliage.
- Steady the environment. Move it away from cold drafts, AC vents, and heating sources, and keep temperatures stable above 60 degrees Fahrenheit.
- Repot if rot is advanced. Trim away mushy roots, refresh the soil, and water sparingly while the plant recovers over the next few weeks.
| Cause | Tell-tale sign | Fix |
|---|---|---|
| Root rot | Dark spots from center, wet soil, mushy roots | Dry out soil, improve drainage, repot |
| Bacterial or fungal spot | Small spots with yellow halo that spread | Remove leaves, sterilize tools, improve airflow |
| Underwatering | Dry crispy patches, bone-dry soil | Water thoroughly, keep consistent |
| Sunburn | Bleached patches facing the window | Move to bright indirect light |
| Cold drafts | Spots after a chill near a vent or door | Relocate away from drafts |