What is the best way to Building fertile soil

The shortest best answer is compost.

Add organic matter. Organic mster= comppat,steer manuer,

vhickem manuer,organic fertilizer

Compost is best, either store bought or homemade. If you are looking for speed & volume, buy from a nursery or a delivery service that stocks mulch, compost, etc. Depending where you live, they have commercial compost plants, that could be an option.

Hi Linda. I add cow manure, peat moss, and compost to mine.

If you live in agricultural area, find 2 yr old manure from a farmer or ranchers. Grandma said the best is sheep dung, then chicken dung, then any other livestock dung after those two. If you do not have farm and livestock animal manure available, you can buy it in large bags to till into your soil. If you have a lot of clay, you might want a load of sand, we put half a ton in our heavy clay garden of 50 x100 ft. Straw and any organic matter helps, but not new wood chips or sawdust. It should only be added if they are 2 yrs old. Pineneedles, leaves, any organic matter helps in the fall to prepare the soil ahead. Till it well and mix it all in well.