Plant Seed Sterilization

I’m looking for a way to sterilize thistle seed so that it won’t grow. Here’s the trick, though; I need to do it without using a microwave or oven.

Basically, I want to sterilize thistle seeds, but I want to do it in a way that the “fluff” that surrounds the seed isn’t destroyed.

Are there any other methods that guarantee sterilization of the seed? Either via at-home method or industrial process?

Gamma irradiation?

Good old fashioned heat. Most seeds won’t tolerate temperatures above 60oC for more than about 12 hours. That’s still plenty cool enough not to damage the bristles.

In warm weather, you can easily achieve these temperatures by placing the seed in a black garbage bag an leaving it in the sun. You might need to leave it out there for a week or so to get enough time at the high temperatures.

For most seeds, the process works better a high humidities. So wet a couple of paper towels and stick them in the bag with you seed…