Please give an approximate location (nearest city) so we can help you compare options. Climate will play a huge role here.

Oh, of course -- we're in Louisville, Kentucky.

I have a raised bed I'm not using this year because of our drought. I've got it covered with black plastic. The plastic will kill the weeds and, in my case, keep the soil from drying out and turning to dust.

I have been tossing yard waste on the bed all year, turning it into a compost pile so when I do plant I'll have something nutritious to plant in. But that's considered cold/sheet composting, so I don't throw in anything with seeds or disease. When I am ready to use the bed, I will go out with a shovel and turn it all over good, probably tossing in some composted steer manure, about 90 days before I'm ready to plant.

I'm only suggesting this because you said you don't plan to plant in these beds for years. If it were me I'd cut the weeds close to the ground (leaving the cut weeds to lay on top of the soil if they aren't full of seeds), cover the ground with a few layers of cardboard, then cover the cardboard with a thick layer of woodchips. Keep the layer of chips sufficient and you'll have minimal weed issues.

Rodney

I am usually a leader of the cardboard wood chips party, but she has a real chance of exterminating the seed bank. I suggest, like Loribee, black plastic for a couple of summers, with frequent openings, light hoeing, and deep watering, then closing again. In fact, clear plastic is probably best, as some seeds are light sensitive. Open, hoe, water, and close maybe three times during the warm season, then you can cover with wood chips.