In the fall, it is important to give the blueberries a good covering for the winter months ahead. Blueberries do best with a 2-4″ mulch over the roots to conserve moisture, prevent weeds and add organic matter. Bark mulch, acid compost, sawdust, grass clippings, etc. all work well. Buying enough pine mulch to cover three acres of blueberries can be very costly. In our case, Dad cuts down pine trees out of the forest and chips his own pine mulch. He then uses an old modified manure spreader, pulled along with his Kubota tractor, to complete the job.