VERY alkaline soil - what can I grow?

[QueenJane]

I have neglected our garden for many years, just doing the absolute minimum to keep it looking slightly tidy...

In the last few months I've been bitten by the gardening bug, and we've had a serious clear out and tidy up. I want to start growing things and enjoying our garden. There is one area near the patio doors which has been the dumping ground for ash from the fire FOR YEARS. To say that it must be alkaline is an understatement. Nothing grows there. Not even the weeds...

Should I dig it all up and add compost/acidic treatment? Or is there something (like the plant equivalent of a cockroach) that could thrive here?

I’d start by testing the alkaline level of the soil, as you’ve already said it seems too alkaline for anything to grow. If that’s the case dig in soil improver, and composted manure.
Then re test. There are some plants that will tolerate alkaline conditions, but it is better to move the soil towards neutral, if you can, first.