Leaves. Although Begonia can do well in darker locations, the frequency of irrigations must be reduced to counteract the chance of root rot. Common Issues with Begonia Maculata. This is different than other fungal diseases. This will cause rotting to occur and also invite various diseases that begonias can be prone to including powdery mildew, among others. The leaves will turn yellow and dry up. However, the plant will still thrive with higher humidity levels. Each mature leaf can grow in the range of 20 to 25 cm in size. My Begonia Maculata Wightii was sitting next to my Begonia China Curl. When your plant is in warm and dry conditions for too long, the mildew develops. Clusters of angelic white flowers enhance the beauty of this peep in the warm days of spring and summer. Maculata can grow up to 60 inches or 1.5 meters in height. Although mildew is ugly and can disfigure your begonia, the chances are good that the plant won’t die. I have started to see reddened spots on the China Curl, so I believe I need to treat this one for powdery mildew and leaf spot as well. Begonia Maculata Flowers. Powdery mildew, or Oidium begoniae, appears on begonia leaves as a white powder or powdery looking spots. Older leaves that rapidly become yellow are a clear sign of over-watering, usually caused by too little light, with other symptoms include mouldy or heavy soil, stunted growth and a rotten base. Begonia Maculata commonly referred to as the Polka dot Begonia, is undoubtedly one of the most strikingly gorgeous species of indoor plants. Pick any heavily infested leaves from the begonia and destroy them. Begonia maculata is another houseplant that has taken the plant world by storm and is super popular. The Begonia Maculata does well in a potting mix with good drainage using a soil mix with sand and clay. A humidity level of 45% is recommended for the polka dot begonia. A humidifier would be the ideal way to maintain the right humidity levels around the plant. The disease covers your plant’s leaves with dusty mildewy spots. Keep temperatures between 67 to 70°F with high … Powdery Mildew Multiple fungal pathogens can cause powdery mildew on begonias. This disease appears as powdery white spots on both leaf surfaces, stems and … Care for Begonia Maculata houseplant: Begonia maculata is a plant that needs indirect bright light, like to thrive in temperature between 18 degrees C to 30 degrees C, fertilize one in a month, normal humidity range is enough, easy to propagate and regular pruning is required. However, the begonia maculata is prone to powdery mildew that would compromise the beauty of the plant. Your Begonia Pavonina has a Powdery Mildew . Powdery mildew on your Begonia pavonina happens. This exotic plant derives its name from its unique silver spotted leaves and red undersides. I know, I probably should have quarantined the new plant, but we live and learn I suppose.