How long has -ize (or even that upstart, -ise) been productive in forming verbs from other parts of speech?

I'm not sure, but, according to MWDEU (link). it started to annoy people in 1591 (link).

 Quote:
[Thomas Nashe] was none too politely tweaking the noses of his "reprehenders, whom he was apparently pleased to have nettled with his verb coinages ending in -ize. Ever since, it has been possible to raise hackles with newly coined verbs that end in this suffix."


Seems to me younger than the verbed noun route.


Ceci n'est pas un seing.