My Marigolds are about 12-14 inches tall with no sign of a flower....what is wrong or is this normal?
Marigolds come in all sizes. It sounds like you have one of the taller ones and the plants are putting their energy into growth. Once they have reached mature height the blooming commences. Don't fertilize as high levels of nitrogen favor green leafy growth over flowers. Some compost on top of the soil should be sufficient for marigolds unless your soil is quite poor. If bloom starts to lag in late summer, try some liquid fertilizer for a quick boost. Also, if you are having a heat wave, that will delay blooming. Even if well-watered, severe heat is a plant stressor.