Answer:fuchsias, the easiest of which to control would be aphid or whitefly damage. Since you've discovered no pests, and the plants have no history of pests, we'll go through the other possible causes: Pythium rootlet rot which kills back the smaller roots of the plant, or Verticillium wilt, an especially common disease of fuchsias in southern California. You may be able to stem the tide by cutting off the affected plant parts, but if either disease is actually present, your fuchsias will eventually succumb to the disease. Sometimes an insect infestation, especially before the leaves unfurl, will cause the emerging leaves to be distorted when they are fully expanded. This happens to my plants occasionally and I simply pinch off the affected stem. The plant reacts by producing new stems with new, unaffected leaves. Try pinching your plant back and see if new growth looks better. If it doesn't, then suspect a disease and toss the plants and the soil, so it doesn't spread to other plants.
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