They don't brew seeds by default so I got nothing to worry about there.
I am talking about the plants themself. You don't get seeds when the plant is harvested, or cooked. You need to brew/let your dwarves eat it if you want seeds.
Well good thing my dwarves are too stupid to cook, if anything I'll just ban plump helmets from being stewed as my new fortress has a thriving meat industry now.
Seriously, all the mistakes and fuck ups really helped me understand what you need to get going in the long run. And to not forget about migrant waves. I already have a skilled hammer dwarf, a manager/leader/stock keeper, got myself a broker, have my large organized stockpiles going back up, again I got myself a thriving meat industry, found Tiger Iron (which I'll assume can be smelted), and the only threat that I found are a couple of batmen that are stuck in a hole they can't climb out of.
So the first year of Whippage looks really good.
(Yeah, I abandoned my old fort of Passionfountains... apparently its doing well from what I'm hearing.)