In my cupboard there is a spray bottle containing some green liquid and labelled 'weedkiller, poison'. It's sort of true.
I was dipping into Astar's Place YouTube channel and found this. She mixed white vinegar and lemon juice and used it as weedkiller. I found this intriguing. I am nervous around 'proper' weedkillers.
As I was looking at the video, another one came up in the list at the side, and I had a look. It was a video from Revolutionary Gardens comparing home made weedkillers to Roundup in a scientific way, link here. It was quite interesting and it showed that actually Roundup probably was the best but white vinegar wasn't too bad. So I got one of the stash of spray bottles (they were on offer from Approved Food and I bought a load) and filled it with white vinegar mixed with a serious dollop of washing up liquid (dish soap). On Thursday I went out and had a spray. It's rained a lot since then, but the weeds are definitely looking battered. Even the dandelions are looking sorry for themselves, and they are robust. I had another spray just now as it was looking clear. It has, of course, started to rain, but I'm hopeful.
I think the vinegar squirting, if it works, will have a lot of advantages. I am pretty confident that the vinegar will do no permanent harm to the garden, which is a state anyway (washing up liquid has strict rules about how quickly it has to break down). It is relatively inexpensive, especially if I can get five litres for under £3. Also, while it smells a little peculiar in the garden, it will keep the local cats away.
I've labelled the bottle 'weedkiller, poison' to make sure it's not squirted around. A blast in the face would be unpleasant. Besides, while it isn't the same as cyanide, drinking a glass of vinegar and washing up liquid probably wouldn't be very good for you.