What a wild weather ride we’re on! Dry as a bone through June (we should have been irrigating in mid April, it was that dry), now we’re soaked deeply. But no complaints, farmer friends in southern Vermont received 20 inches of rain in July. We only got 5 inches in July and that was plenty. All the crops have been happy to have some warmth and sun this week.
A task that we do most years as early as possible in the spring is seed some of our vegetable land to a grass, clover and alfalfa hay crop. It’s excellent practice to give land that grows vegetables a long term break.
Two important methods of reducing pests and diseases in organic agriculture are maximizing soil health and biodiversity and breaking the life cycle of pests or diseases. Crop rotation is part of the solution, move the crop away from where it was last year, hopefully leaving behind the pests/diseases that were living alongside that crop. We have always rotated crops and we have always used a cover cropping strategy to replenish the soil with nutrients, planting a crop like buckwheat or ryegrass and then tilling it back into the soil to feed the next succession of veggies. Around 6 or 7 or so years ago, after many years of rotating and cover cropping our land, we recognized that the soil needed more. Less than a year was not long enough for the soil to be fully rejuvenated. We started to experiment with longer field rest time by planting hay crops. It took a few years to dial in our new approach. We are finding that two or more years in grass and legume sod is ideal for building soil structure, increasing organic matter, and reducing weed, pest and disease pressure. Having enough legumes in the the mix is key, the legumes fix nitrogen in the soil that the grass (and later the veggies) draw out. 
Most years there is a few week window in the spring during which it is easy to get the tiny grass and clover seeds germinated and growing. This year we thought it was going to be dry so we started when there were still snow patches on some of the fields. We eked out just enough moisture to get a good stand and watched neighbors plant 10 days later and have nearly complete failures. Most years it would be very bad practice to sow a hay field in July, this year it would have worked great with the consistent rain. Anyway we mowed these fields once already, and now the clover is coming back strong and about to go into full flower. A field full of purple clover flowers is a pretty sight, and a sign that the powerful legume is fixing nitrogen that future crops will feed on.