Please Note... these are the newer seeds, not the old seeds from the original seed spawn that came from Boglings and Bog Creatures. Unlike the old plants, these seeds do not generally produce their own seeds. Some do produce resources.
Here's a chart I made for myself, when these new seeds came to be. Not shown is the Blue Flax. I beleive that spawns in the 2nd group, with the Foxglove.
Please note: There is a BUG in play at this moment that does make the Spider Tree spawn seeds and will spawn as colored plants. These are NOT rare! Also effected by BUGS are the Tri-Barrel, Prickly-Pear, and the Single Barrel Cactus. This plants will not give the same seeds back when cross-pollenating them. Best to only pollenate them to themselves or just leave them alone to produce seeds.