What Is White Powder on Rubber Plants?


According to Arizona State University, rubber plants, which belong to the genus Ficus elastica and are also known as rubber trees and India rubber figs, are prized for the large, glossy, and exotic-looking leaves that they bear. Rubber plants originate in Malaysia and India and are able to thrive in the outdoors in USDA plant hardiness zones 9 through 12. They are also suitable for growing as houseplants inside in colder areas. Although rubber plants normally do not suffer from significant illnesses, they may, like the vast majority of other plants used in landscaping, sometimes acquire powdery mildew fungal infections. These pathogens cause a white powder to develop throughout the leaves surfaces of infected plants.

Powdery Mildew Symptoms

The powdery mildew fungus is responsible for the development of a powdery growth that ranges in colour from white to light grey and may be seen on the surfaces of rubber plant leaves or shoots. In most cases, the mould first appears as a few discrete spots or patches before spreading over the surface and eventually covering it entirely. Both old and new foliage may get infected with this illness, although the young, succulent leaves are most vulnerable to it. New growth on damaged rubber plants may be stunted, distorted, or coated in the white powder. This condition may be fatal. According to the Missouri Botanical Garden, affected leaves of the rubber plant will often become dry, yellow or brown in colour, die prematurely, and fall off the plant. The signs of powdery mildew may be unsightly, yet the illness very rarely results in the death of plants that have been affected.

About Powdery Mildew

Powdery mildew is a fungal plant disease that may move quickly to new plant hosts when strong gusts of wind are present. According to the University of California UCNFA News, in contrast to the pathogens that cause other types of mildew infections, powdery mildew pathogens are able to sprout and infect new plant tissue even in the absence of free water. In order to flourish, the fungus need cool, shaded environments with temperatures between 60 and 80 degrees Fahrenheit and humidity levels that average approximately 95 percent. This condition is particularly frequent during the spring and fall seasons, namely when warm days are followed by chilly nights.

Cultural Controls

If you follow a few cultural techniques on your rubber plants, you may be able to avoid or lessen the amount of powdery mildew. It is sometimes possible to prevent or treat this fungal illness by positioning plants in areas that get full sunlight; nevertheless, rubber trees may survive in full sunlight only in regions with lower average temperatures. Plants that are grown outside and thrive in hot, sunny areas prefer partial shade to full sunlight. According to the University of California Statewide Integrated Pest Management, if this is the case, you should prioritise decreasing the relative humidity levels around your plant by performing pruning to improve air circulation, increasing the spacing between plants, and avoiding the use of methods that involve irrigation from above. The fungus that causes powdery mildew may be eradicated from the plant population by performing selective pruning and disposing of sick plant leaves.

Chemical Control Methods

Neem oil, sulphur, horticultural oils, and biological fungicides containing Bacillus subtilis are some options that are less harmful than the commercial fungicides that are used to successfully prevent or eliminate powdery mildew disease. The Old Farmer’s Almanac suggests spraying your plant with a solution that contains around one tablespoon of horticultural oil, one tablespoon of baking soda, one teaspoon of dish detergent, and one gallon of water. This will prevent powdery mildew disease from developing on your plant. If you are going to use neem oil, be sure you combine it according to the directions on the bottle. Neem-based remedies have the potential to completely eliminate the condition in as little as one day. Spraying your rubber tree plant with the solution so that it fully drenches the leaves is an effective method for either avoiding or getting rid of powdery mildew. Continue applying the solution once every seven to ten days until the surrounding circumstances are no longer favourable for the formation of powdery mildew.