Our weather patterns and conditions in the Central San Joaquin Valley are directly influenced by the water temperatures in the Pacific Ocean. During the last few years water surface temperatures have been warmer than average creating an El Niño condition which brought heavier-than-normal winter rainfall to our valley.  Sea temperatures moderated to about average or neutral this summer, but a cooling trend from September to November is predicted to create a 79% chance of La Niña weather conditions for this winter. The long range forecast shows wetter-than-normal weather in Northern California this winter and drier-than-normal conditions in Southern California and (maybe) normal or average rainfall for the Central San Joaquin Valley.

Central Valley gardeners will be busy this fall nursing plants and trees that were severely damaged or replacing those that died during the many and long extreme summer heat spikes that scorched our valley landscapes.  Last winter's heavy rain from atmospheric rivers created by the El Niño caused severe flooding that also damaged plants and trees and changed our landscapes. 

The importance of enhancing soil conditions in our gardens so that the soil's drainage and water retention capacities are greatly improved cannot be overstated. Our plants and trees will have better chances for survival in the harsh weather conditions we're experiencing if the soil can hold water and nutrients longer in drought periods and if runoff is reduced during heavy rains.

Adding large amounts of organic matter to garden and agricultural soils has been shown to have a notably positive effect on soil structure. According to the USDA Natural Conservation Service, “Soil organic matter holds 10 to 1,000 times more water and nutrients than the same amount of soil minerals."

The same article also mentions that as the added amendments change the soil's structure, several other good things happen. The soil's surface is stronger and more stable which inhibits erosion by water and wind. Less erosion and less runoff reduces the amount of particles (dust, allergens, pathogens) carried into the air and into the water system.  

Soils that are heavily amended with organic matter are chock full of beneficial fungi, microbes and micro-organisms, all of which play many roles in improving soil structure and health.  The long thread-like hyphae that extend out from beneficial fungi help bind soil particles, attach to plant roots and draw up additional water for the plants. Beneficial fungi and micro-organisms can attack and kill off disease pathogens or out-compete them.  

Amending garden soil with organic matter at every planting is a first step in improving the soil structure. Diversifying crop types, crop rotation and tilling in cover crops are additional steps which home gardeners can take even on a small scale. Bagged compost and humus are easily found at nurseries and garden centers, as are mushroom composts, earthworm castings and tree bark composts.  As always, fresh and homemade is better. Homemade compost will contain much higher numbers of more active beneficial micro-organisms and fungi. Live worms would be an added bonus.