I’m with @txpanhandle1 on the tillage radish being overhyped as being able to break up soil compaction.
While I’ve not planted them on any scale, several years back, when I was renovating a pasture, the no-till drill rented from NRCS had a little tillage radish seed in the seed box, leftover from the previous user. I cleaned out what I could, and tossed the seed into a little garden spot near the house, where I’d previously grown tomatoes/peppers, and currently grow collards, mustard & rutabagas. I had not tilled or dug that bed that fall. The radish seed germinated and grew, but virtually all bulb growth was above ground, with minimal root penetration into soil beyond an inch or two.
I won’t be investing in a lot of ‘tillage radish’ seed.
FWIW re: subsoiling- on the silt and clay panned soils of upstate NY and New England, which give about 12" of moderately drained loam over deeper layers of semi-pervious material, University extension spent about 40 years telling us it was a waste of time, money, and horsepower. Better off just to manage your surface runoff with swales, dead furrows, etc. and live with the rest. I don’t know what they’re saying now, but as late as 2000 or so that was the orthodoxy.
in a small space isn’t this similar to broad fork lift and mix? lifting and aerating, sprinkling bit of compost into the holes, then letting the ground relax
I’ve been eyeing broadforks and this seems to be a bigger scale of that idea. to get air deep under without really pulling up everything to till
