Do Marigolds Bloom Each Year?

Will Marigolds bloom again the next year if you leave them alone or do they have to be replanted each year?

Marigolds for the most part are considered annual plants but you can find some varieties such as the Citrus Scented Marigold, the Mexican Mint Marigold, and the Tagetes Lemmonii, that are perennials.

If you remove the head of each flower once it die and let it dry out and remove the seed from the inside, the next spring you can take those seeds and spread them and marigolds will bloom that same year