Are you starting plants indoors? March appears to be your month for indoors starts.
How many adults and children will be eating from your planting? With this, I can give you an idea of optimum bed space needed.
Did you start onion seed or using starts? Onions are only one planting a year although scallions can be succession planted.
Kale, Broccoli, cabbage, carrot, beets and turnips can be succession planted...
Cauliflower heat sensitive so a possibility.
Broccoli, cabbage, cauliflower and celery all recommended for Indoor starts... sometimes Kale.
Celery typically only one planting with indoors starts in your are planting in late February.
Indoors starts in March are Celery, cabbage, broccoli, cauliflower and kale.
Thoughts?