Adding organic material into the soil is the best way to improve aeration, drainage and the soil's overall health, according to Washington State University. Using wood chips as an organic soil amendment has a minor drawback--the action of decomposition of the wood product will tie up nitrogen. You will need to add nitrogen to the soil when you add the wood chips are layered to improve the soil's overall health.
Layer 2 inches of wood chips, as a soil amendment. You can do this at any time of the year, although Washington State University advises that fall is the best time.
Broadcast 1 lb. of nitrogen-rich fertilizer over a 1,000 square foot area.
Work the wood chips and nitrogen fertilizer into the soil with the rototiller. Incorporate the two materials into the soil to a depth of 6 to 8 inches.
Leave the amendment and nitrogen fertilizer to decompose over the winter.
Conduct a soil test before working the soil for spring planting. Contact your local agricultural extension service for the process and procedures in conducting the soil test or use a home test kit.