I wondered if anyone could advise on this.

I currently live in a smallish garden flat. My two cats have access to the garden via a cat flap. My garden is mostly decking/gravel, but also has a couple of big flower beds and several flower pots. My garden’s fence has plenty of gaps in it that are easy for a cat to slink to, as do those of my immediate neighbours. This means that my cats have access to quite a few gardens, some with grass, some with lots of flower beds, etc. They can also, at a pinch, access a few small bits of scrubland that’s owned by Network Rail & where nobody ever goes that I’m aware of.

I am pleased to say that I’ve no idea where they go to the toilet. I presume not in my garden, although I couldn’t say for sure. Out of sight, out of mind.

I’m thinking about moving to a bigger place [need more space for family]. One I looked at today is quite nice and has an OK sized garden by city standards, bigger than the one I have now, although again with no lawn [it actually has some kind of weird astroturf fake lawn, the owners seem a bit odd, but that’s another story]. My concern is that, due to a preponderance of extremely tall walls either side of the house [with trellises on top – too high even for a cat to climb], my cats will be more or less restricted to this garden.

What I’m wondering is, if I moved into the new place:

(1) Whether I’d need to plant some grass, if only a small patch, to enable the cats to eat a little bit of it to aid digestion & whatnot; and

(2) What, if anything, I’d need to do to make sure that the cats were still able to go to the toilet outside. Could I maybe [say] just leave some big flat plant trays filled with soil or something and clean them out once a week? Some kind of compost heap type arrangement? What do people do in this situation?

Thanks in advance to anyone who can advise.