I’ve done a lot of study of applying wood chips recently to my hobby orchard and my garden. The information below is from my personal experiences and the “back to eden” tours on YouTube (by Paul Gautschi). Mulching with wood chips is AWESOME as you don’t need to fertilize your trees, the mulch holds in the water so very little if any is needed, plus very few weeds grow, and those that do are easily pulled out by hand. However there are a few vital points to make wood chip mulch work:
1/ NEVER till the wood chips into the soil. They rob nitrogen from the soil and plants as they break down if you do. 2/ If planting in a garden with wood chips, always plant the seeds in soil UNDER the wood chips, with the wood chip pulled away in a furrow. As the plants grow from the seeds you can slowly move the chips back over the stems of the plants. If you plant the seeds directly into the wood chips they start to grow okay, then shortly thereafter stall out and turn yellow, again due to the nitrogen being taken by the decomposing wood chips. 3/ I have had great success covering lawn grass with construction paper (available at Home Depot, cheap in big rolls), put a layer of grass clippings or composted cow manure over the paper and under the wood chips, and by next spring the original grass dies, composts, and feeds the plants. No need to do all the hard work of removing sod around fruit trees! 4/ Wood chips are a LONGER TERM solution. Don’t expect immediate results similar to putting fertilizer onto trees/plants. I’d say each year gets a bit better, and the maximum benefit doesn’t hit until about the 3rd year. The area where the wood chips touch the soil is where all the “action” happens, so if you put any kind of “plastic weed fabric” in this area you are defeating the purpose. Only use construction paper or cardboard, both of which degrade shortly. You do need to add more wood chips each year as they compact down as they compost at the soil level. But no more watering, no more fertilizer, and very little if any weeding, and super healthy and productive fruit trees is the result. And each year gets better and better! The soil becomes alive and you will not believe the numbers of fat, healthy earthworms under the mulch and how much the soil will improve. The best time to do this is late fall, just before winter/snow sets in. The melting snow the next spring gets things going well with this mulch. You can add a bit of lawn clippings, cow manure, fall leaves, etc. to the wood chips as this helps break them down if you want to. But all in all, no rush, its a longer term project with great results I find.