Quote Originally Posted by Vidu View Post
You'll never get seeds when using flowerpots, since seeds are only generated via crossbreeding so you need at least one adjacent plant (putting two flowerpots next to each other doesnt count).

Planting them in a garden bed has a chance to yield certain seeds if you crossbreed with the correct plants. There is no known crossbreed that will give you new Thavnarian Onion Seeds from a Thavnarian Onion plant, though. You can crossbreed them with gridanian or ishgardian tea for a chance of other chocobo food seeds (like Sylkis and Mimett), which in turn can be used in a crossbreed with jute to potentially produce new Thavnarian Onion seeds.
Crossbreed chances increase by using Thanalan Soil, but getting seeds isnt 100% and some of those crossbreeds have more than one outcome. I'm running a cross like this atm and my personal experience (with a way to small sample size to say anything definitive) is that I'm getting about a 50:50 split between mandrake-seeds and chocobo food-seeds from my Thavnarian Onion crossbreed.
Is there any use in those crossbreedings, except for the "fun" of it?

The reason I asked was the information on the linked page, that seems to indicate there's a chance for 1 seed no matter topsoil. If this isn't correct I'll just continue planting them in flowerpots.

https://ffxivgardening.com/seed-details.php?SeedID=46