Would not have expected to see a Bellermine on a furry site...my ancestors would have used these back in the 17th century...

Also, dare I say it? First.

Oh yes...the bottle was usually...filled...before burying. What was it filled with? Human urine and nails or pins...and they are still being found on sites in England...

That's fascinating! Do you know what kind of stuff you have to put inside?
There are similar practices in some modern religions and there is always some magical ingredients that you have to put inside, That would be interesting. Witchcraft always fascinated me and scared me at the same time.

Is the design yours or you use a reference?

The article gives some idea of the sorts of stuff that goes in.

As for the design, it's based loosely on several similar bottles depicting the "Green Man"

You did a great job! I could not put it with any particular culture, but it looks like something from the time of the Druids or some other Pagan religion from Europe. The drawing itself has the style of an illustration from an old history book.

A Bartmann jug! Never heard of them being used in that way, but burying something below the doorstep to ward of evil spirits is a common practice. That could be everything from sheets with spells, small animals or a human placenta.
These jugs have an interesting story. While the design was just a matter of fashion, they became status symbols in some parts of Africa and are still used for brewing and handed down from generation to generation while you won't finde any outside of museums in Europe

Very interesting, I like all the leaves and designs! It reminds me very much of a Greek burial urn, or perhaps of the Dungeons and Dragons God of nature... what was his name... Boccob? Something like that. The acorns were a good touch, also, I don't think flowers would have worked as well. That would've made it too cheerful looking, given its rather serious purpose.

It's based off a real bottle that involved a real English nature spirit. Check Wiki for "the Green Man"