Every time I meet him, I learn some more about farming. Here are some quick highlights of what I have learnt over the years (Go here for a good talk by Deepakbhai):
Basic Theories behind Chemical and Organic Farming
- In inorganic farming (as in most of science), you try and remove (kill) all variables like microbes in the soil, earthworms, insects etc. Then you add the chemicals you believe the plant needs. Then you add specially produced hybrid seeds, you water the plants/hope for rain and collect the yield. You then burn the rest of the plants that are standing in your field to prepare the field for the next planting.
- Unfortunately, most biological systems aren't ever that simple. Plants, microbes, worms, insects, birds all grow in an ecosystem where they support each other. A plant doesn't only take 3 or 10 elements from the soil - it takes a whole host of them - some that we might not have figured out yet. Since the chemicals only reflect the elements we know of, we can't do much about the unknown. Also, there is often a lot of complexity behind the form(s) in which elements need to be present for a plant to be able to absorb them...
What Deepakbhai proposes is beyond organic - farming without any pesticides at all, with yields greater than you get through inorganic and with zero external inputs (=> no costs other than labor)
Plant physiology
- Tilling your soil exposes your microbes/carbon to the sun, which kills the microbes/produces CO2 and loss of organic carbon. You don't want to till, but dig a small hole whereever you need to plant (or in some cases, just scatter the seed on the soil, if it is rich enough.
- Pruning is an important part of yield control - if you don't prune, you are wasting the plant's energy in the upkeep of non-productive branches (there are some great rules around pruning that I am skipping)
- Feeder roots of plants are within the top 1-2 feet for most plants - this is the only part that can absorb elements from the soil - this is where you want the nutrition
- Most of the edible produce we want from plants are from carbohydrates - after harvesting, take the remaining part of the plant (if it is an annual), chop it up and let it decompose to enrich the soil - don't burn it/uproot it and throw it away - burning will just release more CO2 in the atmosphere and cause you to burn away useful elements. It will also hurt the microbes in your soil.
- Organic pesticides are not okay. Pests tend to destroy weaker plants, which will automatically allow the stronger plants to self-select. The nutrients in the weaker plants will go back to enrich your soil.
- If you have larger amounts of organic carbon in your soil, it allows your soil to absorb more water from the atmosphere and so need less water
- Plants don't need a lot of water. What they need is moisture around the feeder roots, to allow easier ion exchange between the roots and the soil
- Rice doesn't need a lot of water to grow. The only reason farmers flood rice fields, is because the roots of rice plants can breath even when water logged, whereas the weeds can't. It is a way of doing weed control/labor saving.
- Feeder roots are most active on the periphery of the plant - ie. around the canopy of the tree/bush - where the plant would direct most rain water. Don't water at the trunk of trees, but at its canopy.
- Mulching around your plant is critical to weed control and water loss and root burn prevention.
Trees and their benefits
- Trees play a critical role in having a healthy farm
- Around every few acres of land, you should have a row of trees
- Trees reduce the micro-temperature of the farm - preventing burning of the plants and reducing their water needs
- Trees take water and elements from deeper in the soil and bring them up/make them available
- Trees anchor your soil
- Trees provide shelter for birds
- Trees provide biomass - both for firewood and for create new layers of soil
- Trees break strong winds to prevent erosion or hot winds destroying crops
- And obviously, trees can yield fruits and/or wood for consumption/sale.
Birds and Bees
- Birds help in seed dispersal
- Bird poop is a great fertilizer
- Birds are a good natural pest control mechanism - will control rats, snakes
- One interesting way DB told me to figure out if a farm is organic - see if you can see a lot of butterfly around the farm - if there are, the farm is organic. Otherwise they aren't.
Marginal farmers
There are two models that DB promotes:
- A 10 Guntha Model
- 10 Guntha's is one quarter of an acre. Most farmers have more than that much land.
- Using DB's techniques, 10 Guntha's can produce enough to house, clothe and feed a family of five and have savings left over
- A 1 Guntha Model - Gangama Mandal
- This is a model for a mother to keep her children fed even if the family has no other source of income. It should at least help get rid of the problem of death due to malnutrition that is still common in India
Ok. That was a pretty long post. There is a lot more that I could write and a lot more you could learn if you spend some time listening to DB's video (link at the top of my post)