Plant Growth and the Sun

Several years ago in the VegHeadz garden, we planted the same crop in a completely sunny area of our garden, and in a spot that had shade for a portion of the day. The difference in growth between the two areas was remarkable and served to demonstrate very plainly why providing vegetable crops with lots of sun is advised.

It takes more than just organic matter to produce healthy soils and abundant crops. There must also be plenty of sun for photosynthesis.

John Kempf, founder of Advanced Eco Agriculture, and an expert in the field of biological and regenerative farming, claims:

"It's healthy plants that create healthy soil. It is the process of photosynthesis where plants sequester carbon dioxide from the air, producing sugars, sending it out through the root systems as root exudates that builds organic matter. This is what builds soil health."

According to Kempf, when you increase a plant's photosynthetic capacity by providing access to more sun, the spike in photosynthetic efficiency produces more sugar and sends it down out through the root system as root exudates.

Soil bacteria then consume the additional sugars and multiply more aggressively. The soil bacteria can't produce their bodies from just sugars, they need minerals to do so. As the bacterial population increases, it mines more minerals from the soil to incorporate them into its cells.The bacterial cells are then incorporated back into plant root systems with all the additional nutrients.

Kemp theorizes that as the plants absorb these microbial metabolites, they can now access an abundance of nutrition and produce more energy than they need to sustain themselves. Plants then begin storing the surplus energy in the form of lipids, plant fats and oils, and transmitting lipids out through the root system, in addition to the carbohydrate exudates. Because bacteria cannot digest lipids, this will now trigger very strong fungal digestion. An increasing colony of mycorrhizal fungi and other beneficial fungi in the soil profile begin consuming the lipids. As fungi metabolize the lipids (along with carbohydrates and organic matter) and digest them, they break it down over and over and over again and eventually release it into the soil profile as humus.

In this way, Kemp theorizes, more sunlight amps up the process of providing nutrients from photosynthesis, soil minerals, and organic matter, and increases plant growth and yields.