As far as I am aware, tyres don't generally go for about 4,5 or 6 years.
One contributing factor is UV, so if the bike is stored away in a garage that generally helps. Though UV isn't the only thing that ages tyres.
So if you are going to only ride the bike now and again, go for something softish, plus I assume you won't be riding it on cold winter days when softer rubber can struggle to get up to operating temp. Otherwise you'll end changing the tyres due to ageing (usually shows up as cracking on the side walls) rather than wear and tear.
One wee tip is to make sure you turn the tyres now and again, plus keep correctly inflated. With bikes that sit stored away for long periods the tyres can go off round, all that weight sitting on the same bit of tyre all the time. Just turn the tyre a bit every few weeks. You'll know if the tyre goes off round as the bars will vibrate and the bike will shake it's head hard now and again if you pressing on. It usually works it's self out after a while though but not fun till it has done.