I usually sow my seeds outdoors first weekend in April, some start earlier. I've never grown in containers so can't comment there. I've found them slow to germinate.

Thankyou.
Nila

I'm going to experiment with carrots in containers, myself this year. It's recommended to grow round, or shorter varieties in containers (the container will have to be at least one foot deep and a foot in diameter.) If you plant long varieties, you'll need a container at least 2 feet deep (1 1/2 ft. diameter.)

Here is a link that might be useful: Carrot seeds