The EU has uncultivated land subsidies. To avoid overproduction of food and overexploitation of the land, the EU pays farmers to keep their land uncultivated. Some countries, like mine, force farmers to uncultivate their land once every N years, and, of course, they get subsidies for this.

In my region, farmers will plant flowers and let weed grow, since they're not putting any pesticide. They let the flowers and weeds die and rot at the end of the season. This way, they dont have to put as much fertilizer the next year. I've always seen these uncultivated fields full of bees and other pollinators in summer.