Fuschias grow year-round outdoors in mild climates, but die back in northern regions. Fortunately, they make good container plants and can be brought indoors during the winter months. Aphid infestations cause damage if not death to outdoor fuschia but are rare indoors, unless the plant is already infected when you bring it in for the winter.
Aphid infestations usually do not affect houseplants, unless a plant was infected at the nursery or while outdoors. But aphids can quickly cause damage to fuschias, including stunted growth, deformed leaves and black sooty fungus on the leaves.
Aphids usually live on the undersides of fuschia leaves. They are small, pear-shaped, sometimes winged and are most often light green, although they may be red, gray or brown. Aphids excrete a sticky substance called honeydew that can be seen on the upper leaves, as well as on hard surfaces around the plant.
Washing plants thoroughly before bringing them in the house will prevent infestations. Checking fuschias weekly for insects will prevent aphids from causing severe damage. Additionally, healthy plants are better able to ward off aphid attacks. Fuschias need a balanced 20-20-20 fertilizer every two weeks during blooming, as well as evenly moistened soil.
Washing an infected plant with a solution of 1/2 tsp. dishwashing liquid diluted in a quart of lukewarm water will destroy most aphids. Aphids can also be removed by pruning out affected parts. Garlic oil or hot pepper wax sprays are safe and effective at controlling aphids.
Insecticidal soaps, labeled for houseplant use, are effective at treating aphids. The soaps should be applied outdoors and must be sprayed on the tops and bottoms of leaves. These soaps are only effective when wet, so reapplication may be necessary.