hey there Matthew. Years ago i made some seed bombs of various old seeds, including Ech purp, and turned out with no success at all, but thats not to say that 1. the seeds were tooo old (i know this is rarely true with wildflowers, but sometimes it is the case, as they were stored in a Greenhouse) or 2. might have been a problem with my compost... in any case, i look forward to hearing what others have come up with.
I know Ech. needs to be wintered, whether in a fridge or in the landscape, they need some cold downtime before they will sprout. So, by chance you threw out some bombs in the spring with no results, wait a year and you might be suprised what comes up next year! good luck!
I'm pretty sure they are one of those seeds that need light to germinate or maybe only a very light covering of soil. I keep having plants pop up near stumps and other odd places where I suspect a bird 'deposited' the seed, maybe only lightly covered in bird poop?
I've tried just scattering the seed and have no luck, but one year after reading that they need light, I planted them in a flat pressed into the surface of the soil and covered with glass to keep the seed moist...I had good germination then.
I know the finches love the seed so now I leave my seed heads out all winter and wait for surprise plants to show up
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