Round-leaf Calathea with Yellow Leaves: Causes and Solutions
Calathea orbifolia
Is your Round-leaf Calathea showing yellow leaves? Discover 11 possible causes and how to treat them.
🔍 Possible Causes (11)
Leaf Spot
Leaf spot is a common fungal disease caused by various pathogens including Alternaria, Ascochyta, Colletotrichum, Septoria, and Venturia. It primarily affects leaves, causing discolored spots that can lead to premature leaf drop if left untreated.
✓ Related symptoms:
- • Circular brown, gray, black, or yellow spots on leaves
- • Yellow halo surrounding spots
⚡ Quick Fixes:
Remove all visibly infected leaves
Bacterial Leaf Spot
Bacterial leaf spot is a plant disease caused by bacteria in the Xanthomonas and Pseudomonas genera that affects various ornamental and edible plants. The bacteria infect leaves through wounds or natural openings, causing characteristic lesions that can lead to premature leaf drop and plant weakening.
✓ Related symptoms:
- • Brown or black lesions with yellow halos
- • Leaf yellowing and wilting
⚡ Quick Fixes:
Remove infected leaves
Scale Insects
Scale insects are small sap-sucking pests that appear as brown, shell-like bumps on plant stems and leaves. There are over 25 species, divided into armored (hard) and unarmored (soft) scales. They feed by piercing plant tissue and extracting sap, which weakens the plant and can lead to yellowing, stunted growth, and even death if left untreated. They also excrete honeydew, which attracts ants and promotes sooty mold growth.
✓ Related symptoms:
- • Yellowing or chlorotic (pale) leaves
⚡ Quick Fixes:
Step 1
Overwatering
Overwatering occurs when plants receive too much water, depriving roots of oxygen and causing root rot. This environmental stress is one of the most common causes of houseplant death, as waterlogged soil prevents roots from breathing and functioning properly.
✓ Related symptoms:
- • Yellow or brown limp, droopy leaves that feel soft and mushy
- • Dropping leaves (both old and new) that may be green, brown, or yellow
- • Brown spots or edges with yellow halos on leaves (bacterial infection)
⚡ Quick Fixes:
Step 1
Aphids
Aphids are small, soft-bodied, pear-shaped insects (1/16 to 1/8 inch long) that feed by sucking nutrient-rich sap from plants. They reproduce rapidly and can quickly weaken plants, causing distorted growth and transmitting plant viruses. Aphids come in various colors including green, black, red, yellow, brown, and gray. They secrete honeydew, a sticky substance that attracts ants and encourages sooty mold growth.
✓ Related symptoms:
- • Clusters of soft-bodied insects in various colors (green, black, red, yellow)
- • Curled, distorted, or yellowing leaves
⚡ Quick Fixes:
Step 1
Rust
Rust is a common fungal disease caused by fungi in the order Pucciniales that affects a wide variety of plants. The disease gets its name from the characteristic orange, yellow, or reddish-brown pustules that appear on leaves, resembling metal rust. This obligate fungal parasite requires living plants to survive and can cause significant economic losses in agricultural crops.
✓ Related symptoms:
- • Raised orange, yellow, brown, or red pustules on leaf surfaces
- • Premature yellowing and leaf drop
⚡ Quick Fixes:
Immediate Pruning
Root Rot
Root rot is a serious fungal disease that affects the root system of plants, causing them to decay and die. It is primarily caused by overwatering, poor drainage, or soil-borne fungi such as Pythium, Phytophthora, Rhizoctonia, and Fusarium. The disease thrives in waterlogged conditions where roots are deprived of oxygen, making them susceptible to fungal infection.
✓ Related symptoms:
- • Yellowing or browning of leaves
⚡ Quick Fixes:
Emergency unpotting
Spider Mites
Spider mites are tiny arachnids (less than 1/20 inch long) related to spiders and ticks that feed on plant sap. They thrive in hot, dry conditions and can cause significant damage to ornamental and vegetable plants. During severe infestations, crop losses can reach 14% or higher as these pests disrupt vital plant processes including photosynthesis, carbon dioxide absorption, and transpiration.
✓ Related symptoms:
- • Tiny yellow or white speckles on leaf surface (stippling)
- • Leaves taking on yellow or bronzed appearance
⚡ Quick Fixes:
Step 1
Fusarium Wilt
Fusarium wilt is a serious fungal disease caused by the soil-borne fungus Fusarium oxysporum. The fungus invades roots and blocks the water-conducting vessels (xylem) of the plant, causing progressive wilting and eventual death. Host-specific forms of the pathogen exist that attack different plant species.
✓ Related symptoms:
- • Asymmetrical yellowing of leaves (one side of plant or leaflets)
- • Pale green to golden yellow foliage
⚡ Quick Fixes:
Remove Plant
Mealybugs
Mealybugs are small, soft-bodied insects covered with a white, waxy, cottony material. They are common pests of houseplants and outdoor plants in mild climates. These sap-sucking insects feed on plant tissue, causing damage, stunted growth, and can lead to plant death if left untreated. They produce sticky honeydew which attracts sooty mold.
✓ Related symptoms:
- • Yellowing or wilting leaves
⚡ Quick Fixes:
Step 1
Southern Blight
Southern blight is a devastating soilborne fungal disease caused by Athelia rolfsii (formerly Sclerotium rolfsii), affecting over 500 plant species including vegetables, ornamentals, and fruit crops. The fungus survives in soil through resting structures called sclerotia that resemble mustard seeds and can remain viable for years.
✓ Related symptoms:
- • Yellowing and necrosis of foliage
- • On fruits: sunken yellow lesions turning water-soaked
⚡ Quick Fixes:
Step 1