Regine_EAMythic;
You get the new plants in black and white by completing the Naturalist quest including the "secret" nest (ie the one you do to obtain the fire seed). So you have an even chance of getting:
1) a random fire seed of the old plants or of the flowery cactus
2) a random black seed (new plants only)
3) a random white seed (new plants only)
http://www.uoherald.com/fof/fiveonfriday129.php
As I understand it, you will see the above when pub 56 hits us.