Well I haven;t played CT in a while but I remember something liek If you let the woman burn it, after the Ocean Palace disaster, if you talk to her in the Last Village or something, she says that she kept it anyway and that when she is reborn she hopes to live in a world full of trees (Possible Fiona Reincarnate?)
^
If i'm right about this, that means that in any case the seeds would have either passed on to Fiona or gone to 2,300AD either through replanting and getting the seeds or just by the Zealian woman never burning it even if we told her to.