A case for conservation agriculture

In my country Kenya, most agriculture is still done the conventional way. This is where land preparation begins by cutting down and vegitative growth, followed by burning of any remaining crop stubble. Next is ploughing the soil, breaking it up into a fine tilth by harrowing, then making furrows and lastly planting. Most of these tasks are done by hand with a few being done by tractor, for the few who can afford it.

The soil being left without any cover from the time of planting to the onset of rain, means that when the rains do come, top soil is usually washed off by the run off. This is not ideal because it causes losses due to seed and fertilizer being washed away. This means less than ideal returns from the crop due to a number of reasons. The first is that in the case of washed away seed, there will either be a less than ideal plant population per acre, or in the case of repeat planting, uneven growth pattern. The second is poor soil due to the added fertilizer being washed away instead of being utilized by the growing crops.

I was once invited by my friend who works in agricultural advisory services to accompany him for a field visit. We went to a large scale farmer who has been employing conservation agriculture on his farm for about seven years. This is a type of zero till type of farming where in addition to minimum soil disturbance while planting, the remains of the previous crop grown and chopped up into small pieces and scattered over the farm.

My first impression when we took the farm tour was just how green and healthy the crop of wheat looked. This was despite the hot climate of the area. When we pulled the mulch at the base of the plant, the soil was still very moist as though it had just rained recently, despite there not having any rain for about 2 months. The other thing I noticed was that walking around the farm, it felt like we were walking on a thick spongy carpet. This was from all the crop residue spread over the farm season after season, for the seven years the farm had employed conservation agriculture.

I noticed too that the neighbouring farms crop of maize didn’t look as healthy and green. The plants looked water stressed and drooping in the sweltering heat, despite all crops growing in the same climatic conditions.

This got me thinking, that if more farmers around abandoned the conventional agricultural practices and embraced zero till or better yet conservation agriculture, their farms would yield better quantities of produce. This would also reduce crop failure and increase food security.

The thing that amazed me most was that the way they farm is not determined by the immediacy of the rains. Once one crop is harvested, the next crop in the rotation is planted whether it is raining or not. This is a far cry from what majority of the farmers in my country do. Land preparation and more so planting is purely determined by the rains and their onset. When the rains delay, the whole farming programme is thrown into disarray.

One other advantage I considered is that, because of the thick mulch created by the crop residue, the soil almost always will have moisture. This would greatly help farmers who do irrigation farming, which is the vast majority of farmers with a water source during the dry periods of the year. Most farmers here argue that during the dry period is when market produce fetches a good premium. This is usually at what I would consider a high cost of production as most use petrol driven pumps to irrigate their farms. If they were to use conservation agriculture, this would greatly reduce their farming overheads, especially as relates to irrigation costs. This in my opinion, will also bring down the cost of produce and increasing food security.

The farm that we visited was highly mechanized, thus enabling efficient farming operations. This I know costs a lot to set up. I however believe that even small scale farmers can borrow and adopt some practices that relate to zero tillage, and better yet, conservation agriculture. This is by reducing and eventually eliminating ploughing, cutting and burning crop residue type of farming. This in conjunction with a good crop rotation system will ensure that my country Kenya and many other African countries to reduce crop failure and even be food secure, while conserving valuable water resources.

I have more thoughts on farming and agriculture which I share here.