Plant care guide
Brown Spots on Coffee Plant Leaves: Sun, Roots or Disease?
Updated
Why does my Coffee plant have brown spots?
Brown spots inside the leaf of an indoor coffee plant usually follow scorch from direct sun, cold, or roots in trouble from wet mix, salts or a nutrient shortage such as iron. True fungal leaf spot is less common indoors, and scale insects or mites can also mark the leaves.
What to do first
Note where the spots sit and whether leaves yellowed first. Move the plant out of direct sun and cold drafts, check the roots and mix, and flush salts if there is a white crust. Turn leaves over to look for scale, mites or orange powder before treating.
Brown spots on a glossy coffee plant are hard to ignore. Before treating for disease, check the setting. A University of Vermont plant pathologist, answering a coffee plant question about leaves browning in spots, noted there are not many foliar fungal diseases inside homes. Her first suspects were nutrition, salts and the roots.
This guide covers spots inside the leaf. If the edges are crisp and brown, see coffee plant crispy leaves.
Match the spots
| What you see | Likely cause |
|---|---|
| Dry, bleached then brown patches on leaves facing the window | Sun scorch |
| Damaged patches or leaf drop after a cold night or draft | Cold |
| Leaves yellow between green veins first, then brown spots, plant dropping leaves | Iron shortage, often with high pH |
| Yellowing then browning, mix wet, roots soft | Overwatering and root rot |
| White crust on mix or pot rim, brown patches and edges | Salt build-up |
| Corky, raised bumps under the leaf that turn brown | Edema |
| Round tan to brown spots that merge, more in humid, crowded spots | Fungal leaf spot |
| Orange or yellow powder on leaf undersides | Rust |
| Brown bumps that scrape off, sticky leaves, or fine speckling | Scale or mites |
Too much sun
NC State’s Coffea arabica profile recommends bright light indoors and partial shade outdoors. UF/IFAS’s coffee factsheet and the RHS both list partial shade. Iowa State Extension’s environmental problems page says leaf scorch is permanent and may lead to leaf drop.
What to do: move the plant back from a hot south or west window, or diffuse the light. Iowa State advises moving plants to brighter light gradually, over several weeks, after a summer outdoors.
Cold
NC State gives 21–27 °C (70–80 °F) by day and 16–18 °C (60–65 °F) at night, and says leaves can drop below 13 °C (55 °F). The RHS keeps it above 15 °C (59 °F) and away from drafts.
What to do: move it off cold glass and away from doors and vents. Trim dead patches if you like; judge recovery by new leaves.
Roots, salts and nutrition
UF/IFAS lists poor salt tolerance, mineral deficiencies and root rot from overwatering among coffee plant problems. The UVM answer suspected iron chlorosis from high pH, since coffee prefers acidic soil. It also warned that overwatering can yellow leaves before they turn brown.
What to do:
- Check the roots. The UVM answer contrasts healthy white roots with mushy brown ones. See our houseplant root rot guide if they are soft.
- If there is a white crust, flush the pot thoroughly with plain water or repot in fresh mix, as the UVM answer suggests for excess fertilizer.
- If new leaves are pale with green veins and the roots are healthy, use rain or distilled water for a while and an acidic fertilizer, per the UVM answer. NC State advises feeding during the growing season.
- Keep the mix consistently moist but not soggy, as NC State advises.
Edema
University of Maryland Extension’s edema page describes wart-like or crusty bumps on the lower leaf surface that turn brown. They are often mistaken for disease. Edema happens when roots take up more water than the leaves lose. Maryland advises more drying time between waterings, especially when the mix is cool. Our edema guide has more.
Fungal leaf spot and rust
Maryland’s fungal leaf spot page describes tan to reddish-brown to black round spots that can merge. Pick off spotted leaves, keep foliage dry, water early in the day and space plants for airflow. Maryland says these steps usually suffice indoors.
UF/IFAS names coffee leaf rust as a disease of the plant. UC IPM’s leaf spot causes list describes rusts as orangish or yellowish spore masses, usually on leaf undersides. Remove affected leaves and keep foliage dry.
Scale and mites
UF/IFAS lists scales, mites and thrips among coffee pests, and the RHS names glasshouse red spider mite. UC IPM notes that, unlike diseased tissue, scales can usually be scraped off. See scale insects on houseplants and our spider mite guide.
The coffee plant hub lists the rest.
References
- NC State Extension Gardener Plant Toolbox: Coffea arabica
- UF/IFAS FPS135: Coffea arabica, Coffee
- University of Vermont Extension via Ask Extension: Coffee plant issue
- RHS: Coffea arabica
- University of Maryland Extension: Fungal Leaf Spots on Indoor Plants
- University of Maryland Extension: Edema of Indoor Plants
- Iowa State University Extension: Diagnosing Houseplant Problems, Improper Environmental Conditions
- UC Statewide IPM Program: Some Causes of Leaf Spots
How this guide was put together: NC State Extension, UF/IFAS, University of Vermont Extension, RHS, University of Maryland Extension and Iowa State University Extension guidance.