QuestionsHow to growVegetable GrowingBrussel SproutsBrussel sprouts 0 Vote Up Vote Down John Anderson asked 13 years ago What causes black spots on brussel sprout leaves . Starts at the bottom leaves and works it’s way up. 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago That is leaf spot disease which affects the older leaves most and plants in a sheltered area too. There is no remedy for home gardeners, except to remvoe some lower leaves to allow air movement.