You can’t have good results in your garden if you don’t start with good soil. Top soils are made up of different components including plant and animal residue, moisture, air space and live soil dwelling organisms.
Organic content provides food for growing plants, food for bacteria, fungi, earthworms and other beneficial organisms. A total organic content should be at least 6% of the top 4” – 6 “of top soil. It also provides a reservoir for moisture. Organic content also provides temperature stability and weed control.
The timing and rate of releasing nutrients is important. Organic material helps to control the amount of fertilizer available at any given time. Air space created by the channels made by various organisms provides space for oxygen, moisture and plant roots. Do not rototill. Tilling the soil collapses this delicate structure. It is better to put a layer of 2” – 4” of compost on top early in the spring to let the nutrients sink in.
One problem in planting is that plants are usually planted too deep. Dig the hole, add some compost and plant the plant so it is higher than ground level, creating a small rounded berm. In time it will sink to the level of the ground.
Be careful where you buy compost. Most box store compost may be over a year old and have little nutrients left. Denny’s commercial formula is 40% forest material, including rotted wood, leave, moss and humus; 50% pasture material, including shredded alfalfa, grass and cover crops; 10% dairy goat & chicken manure; and nutrient supplements e.g. seed meal, kelp meal, high protein livestock feed, goat mils and trace elements. Do not use walnut leaves for mulch.
Other good sources of compost are Hilton Landscape Central Point and the Grange Coop, who has an excellent compost called Green Planet Compost.