Weeds are a constant problem and requires a lot of effort.
We have a 2,100 sqf garden that is fenced to keep the chickens out. It is hard to control grass in fencing, weed eating it eats up a lot of cord and doesn't kill the grass it so it continues to spread into the garden.
So what we do is hit the fence line with white vinegar in the spring. It works better if we weed eat first, more gets to the roots. One application is enough for the season, as you can see here the grass has been chemically burned down to the roots. We also apply it to new garden beds or beds that we've lost control of to kill weeds before planting.
It is cheap, Costco sells 10 liters for $7.99. To do the whole fenceline and 4 long beds cost us around $50. We'll save that in labour 10 times over. Just pour it into my watering can and water.
The vinegar is neutralized in a couple of days and completely safe. We cannot and will not use anything that could possibly harm critters on our farm which includes Roundup. It is also easier and safer to use than a blowtorch.
Also the garden looks messy but it isn't. The other strategy we use is to pile leaves on the beds in the fall. It keeps weeds from growing and adds fertility to the soil. Nightcrawlers (worms) come up to eat them which aerates the soil and they too drop their magic poo.
A total win!