I do the same thing. I get clean pesticide free straw bales very cheap, about the price of a 6 pack. Straw insulates and helps the beds retain moisture. I use it to hill up the potatoes. Then you can leave it over the winter and in the spring your beds will be so amazingly soft and full of worms. The straw blocks the soil from getting compacted by the rain, and worms will run around loosening the soil.

When you remove the straw it’s halfway rotted. Perfect stuff to make compost with, I like to add my Austrian winter peas to the straw, run them through my lawnmower to chop it all up.

Some people here have said wood chips but you should never put wood chips on vegetable beds. It can be okay around your flower beds but use it sparingly. When wood chips break down they use up the nitrogen in the soil. Straw doesn’t have that effect.