How to collect Eryngium seed?

I have had an Eryngium giganteum (Miss Willmott's Ghost) plant for several years, but have never found any seedlings growing around it.

I would love to collect seed from this plant, to try and grow as plants....and some of the flowerheads are beginning to look pretty old, but I am not sure how to set about it. The flowers are incredibly prickly, and I am not sure what I should be looking for.

My other idea is possibly to tie a plastic bag over one of the flowerheads, and let nature take it's course.

Advice would be very welcome.

 

Hi Canna. I have never taken seed from an Eryngium, but the normal method is to leave it as late as possible (to let the seed ripen in situ). The seed heads usually go brown. Then to cut off the whole seed head, and put it in a paper bag, or an open plastic bag (who has paper bags these days?) and leave it for a couple of months to dry. It musn't be a closed polythene bag as it will hold the moisture in and you will get rot.

After a couple of months you can usually shake the bag well and the seeds will start to fall out by themselves. If they don't you have got to gently crush and rub the seed heads.

 

Thank you very much indeed for that Peter. I will do what say!