I planted African Marigolds in the spring. Can you tell me why they have not bloomed yet this year?
A lack of phosphorus, which is responsible for blooming in plants, could be the issue. If your plant is lacking phosphorus, use a phosphorus rich fertilizer or add some bone meal to the soil. Here is more info: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm