I have a patch of oregano--it started with 2 plants, 15 years ago and now it takes over any patch of open ground, so it's 15 feet by 15 feet. I trim the edges by mowing it with the lawn mower. I rototill through the middle of it to plant other herbs (this year basil, garlic, dill etc). Oregano is like mint, it takes over and doesn't need to be covered in winter (zone 4).
I'd be happy to dig some oregano up and share, especially if I could get some horseradish roots in return...anyone game? Another thing I have in excess are honey locust tree beans, I use them for mulch, but they grow new trees all over the place--if anyone needs honey locust seeds, I 'll share. The trick is to start the seeds in a garden, let them grow until you can tell which one's produce pods and which don't, and cull the one's producing pods (female or male) and plant them in the yard. The trees are beautiful.
I harvested the tops of all my dill yesterday (for dilly beans) and I'm drying the rest for winter (dill dip).
To harvest oregano each year I cut hundreds of plants and wash them and shake them off, then put in a big paper garbage bag. When they are dry, I strip the leaves off and into the bag. I pour the leaves into my blender and grind them finely and put them in jars.