Ostracizing thyme

I bought a small container of elfin thyme for my front yard, which the landlord has completely neglected.  I've heard thyme benefits from active neglect as long as it has well-drained soil, but my front yard is solid Bay Clay, so I've decided to ostracize it...that is, to give it pot shards (aka ostraka...pardon the pun).

I had an old Christmas tree stripped of branches, and four shattered clay pots.  I broke all the pots down to <1cm.

I think I'll add in some organic matter as well, to further improve drainage.  Does anyone know how much nitrogen in the soil would be a problem for thyme?  I was going to use a mix of finished compost and browns, but would appreciate advice if this might be harmful.

I'm also not sure quite how deep and how wide to dig, but I know I will arrange for water to drain from the thyme section of the bed toward a more water-loving plant like the roses.

my thyme does best here in a loose sandy soil with a little "doo" compost on the side..but will do just fine without the doo..i keep it out of the clay areas though as i think it does best with sand.

most of my herbs do best with some benign neglect..like just keep the weeds down and water only when in severe drought..i guess that is it.