Just on the off chance anyone is interested.. this is a quick, easy and cheap way to green your lawn up.
Been using it for a couple of months now. You can vary how much you dilute it down but I've settled on 0.5 litre and top the sprayer up to it's 5ltr max. Does my 100 sq mtrs bob on.
Using a watering can to apply it is bollocks.. takes way too long. I put a season long weedkiller on too using the sprayer and seems to be working well so far. I binned my previous sprayer is was crap. This Spear and Jackson one works really well...
https://www.amazon.co.uk/Pro-Kleen-