The Bundleflower seeds should stay viable for awhile.
I germinated mine by boiling water, dumping the seeds in the water and stirring then putting the seeds in some dirt and covering with a humidity tent. They germinate after 2-3 days this way.
As far as my experience goes, the Bundleflower is a somewhat finicky plant and takes a while to grow. I've got some that are about half a year old and about a foot tall, but they're dying down because of winter.
SWIM would suggest experimenting with D. leptolobus which regularly contains a medium level of DMT, unlike illinoensis which has a variable level. Or some kind of Phalaris, which grow much faster.
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