are you sure you didnt just have the farmplots set to grow plants whose seeds you dont have?
No, this is a message you see when you (q) over a plot that can't accept any seeds that are currently available, and it replaces the menu where you would normally choose which seeds to be planted per season. It's possible to still assign seeds to months etc. on a farm plot when you've run out, in which case the farmer(s) will just send a lot of job cancellation messages.
From the wiki, crops by biome type.
—Not Freezing (Dry):
Blade weed
Hide root
Longland grass
Prickle berry
Wild strawberry
—(Evil):
Silver barb
—(Savage):
Whip vine
—Not Freezing (Wet):
Fisher berry
Rat weed
Rope reed
—(Good):
Sun berry
...so, I'm not sure why you wouldn't be able to set up a farm. You've obviously irrigated properly (or found soil), else the game wouldn't allow you to build farm plots in the first place. Can you remember anything at all about the biome information from the embark screen? Perhaps you are unwittingly attempting to grow sun berries (for example) in an evil territory?
How and where did you get your seeds, anyway? (and what are they?!

)