Can marigolds bloom all year indoors?

Question

I want to grow flowers in my apartment with a grow light. I was considering marigolds and just trying to figure out how long they grow for and during what part of the year they would grow. I keep running into the following information:

Marigolds enjoy a longer blooming season in USDA zones 10 and higher, where the weather dips toward freezing later in the winter. Planting marigolds after the last frost in the spring means you should see blooms after 45 to 60 days, and they'll continue until (usually) the first frost of fall.

Source: https://homeguides.sfgate.com/much-cold-marigolds-take-65491.html#:~:text=Marigolds%20enjoy%20a%20longer%20blooming,the%20first%20frost%20of%20fall.

Does that mean indoors they will bloom all year? If not, how long does marigold blooming last indoors and in what month does the blooming period start?

To be more specific, I will be planting orange tagetes erecta or commonly known as African Marigolds.

Answer 1

Tagetes erecta are annuals, so they'll start to die down on their own after a while. I've seen some survive for probably around 18 months outdoors where I am (no frost), but they were in a bad state near the end, with no flowers.

If you keep them indoors, give them enough warmth and light, and maintain good pruning/fertilizing, I'd say you can expect 4-8 months, but they'll flower less near the end.

You can stagger the planting: start new seedlings every 3 months or so, and switch them out as they get old. Should be easy to start from seed, I've been quite successful. Bonus: you can plant different colors!