Fuchsia plants have been a favourite for hanging baskets, houseplants and in partially shaded areas in your landscape, though the plant is considered a tender perennial in USDA hardiness zones 8 to 10. With abundant colourful, exotic looking flowers and lush foliage, fuchsias will bloom throughout the summer months. When yellow spots appear on your fuchsia leaves, it is an early indication that something is wrong. The sooner you can identify the source of the problem and correct it, the quicker your fuchsia plant will thrive again.
Fuchsia rust is the most common cause of yellow spots on the plant leaves. Fuchsia rust is an air born fungus that starts by creating light yellow, irregular spots on the upper leaves of your fuchsia plant that quickly change to powdery rust-coloured larger spots. The fungus generally is noticed in late summer into fall for outdoor plants, but it can affect indoor fuchsias at any time of the year. Fuchsia rust affects the vigour of the plant and soon leaves will begin to drop. Pick off infected leaves and dispose of them as soon as the fungus is found, and follow that by fertilising to increase the plant's vigour. Fungicide sprays for fuchsia rust can be used, but they should be used lightly and with great care, as fuchsia plants can be sensitive to the sprays.
Red spider mites attack the underside of fuchsia leaves, sucking the fluid from leaves and eventually killing leaves and debilitating the entire plant. Leaves that are affected by red spider mites will first show light green spots that turn yellow. Soon the entire leaf becomes yellow, and the leaf falls from the plant. When light green and yellow spots appear on your fuchsia leaves, check the underside of the leaf for the tiny red-coloured pests. You may also discover spider webs. Strong blasts of cool or cold water, either with a hose or shower spray, can knock off spider mites from your plant. Insecticides formulated for eliminating red spider mites can also be used. Regular misting to keep the humidity level up keeps the pests away.
Trace mineral deficiencies can cause yellow spots on fuchsia leaves, though this is not as common. Fuchsia plants that grow in containers that have not been repotted with fresh potting soil or fed for long periods can experience magnesium deficiency, which causes yellow spotting and striping of the leaves. Mix one ounce of Epson salt in one gallon of water and administer it to your fuchsia either by spray misting or water two to three times to correct the deficiency.
Yellow spots on fuchsia leaves can occur when you mist or overhead water the plant if the plant is in direct sunlight on a hot, sunny day. The water spots will burn the tender leaves and cause the yellow spotting. This is particularly true of younger plants. Excessive watering or lack of water can turn fuchsia leaves yellow. Maintain a regular watering schedule to keep the soil evenly moist, but not soggy.