The Sunday Mail
AS we move towards the end of August and bid farewell to the winter season, it is that time again when farmers ought to start thinking about the forthcoming 2023/2024 summer season.
Peter Gambara
Firstly, I will discuss the anticipated below normal rainfall season ahead and then talk about practices that farmers can adopt to adapt to a season like that.
Every year around this time, weather experts come together and give us a prediction of what to expect during the next summer season.
This year, they tell us that an El Niño has already set in, starting this last June and is forecast to last until next February.
As a result of this El Niño phenomenon, several countries in the south are likely to face heatwaves, floods, droughts and epidemics.
Zimbabwe is likely to experience a drought, heatwaves and some flooding.
This El Niño tends to bring below normal rainfall to Southern African countries during the summer season, which runs from November to April of the next year.
This will obviously have an impact on the summer cropping season.
Having been warned of the possibility of a below normal rainfall, we should then ask ourselves: How can we prepare for this, so that we minimise the risks?
Previous El Niño-induced seasons that we have experienced, point to a delayed start of the season, low average rainfall during the summer months, the occurrence of a mid-season drought and a premature end to the rains.
In other words, not only is the total amount of rainfall likely to be below normal, but the length of the season is also likely to be shortened.
I will discuss the practices farmers can adopt under the following topics: lengthening the season; efficient use of water; reducing evaporation; selection of appropriate crop varieties; capturing as much rainfall as possible; and conserving moisture in the ground.
It is crucial that farmers take appropriate actions to try and lengthen the season, by planting early, that is, starting earlier than normal.
This is mostly an option for those with irrigation facilities. Such farmers should plant their crops a bit earlier than usual and irrigate them to germinate, and then let the rains take them through November and December.
Farmers without irrigation facilities can still do early land preparation, so that they can plant with the first rains.
Most farmers make the mistake of waiting for the rains to fall before embarking on land preparation.
However, doing so means you will lose a few precious days and those could be the difference between your crops reaching maturity or not.
So, if you have the means, start your land preparation NOW.
Heavy clay soils can be easily ripped now and then disced as the rains approach.
Sandy soils are a bit difficult to rip now as it is dry.
Those with irrigation facilities should always strive to use efficient methods of applying water.
This often means moving from flood irrigation to sprinklers or a drip system, and also moving from sprinklers to centre pivots.
It is not a secret that efficient water application methods sometimes mean more investment into the irrigation system.
However, the worst use of water by most farmers relates to their inability to properly determine how much water a crop or soil requires.
There are now probes that farmers can put into a field and have them connected to your phone so that at any one given time, you will be told when the crop needs to be irrigated and also when you have applied too much water.
Such a system, including the software, can be installed for about US$1 000.
Farmers should also irrigate during critical stages of crop development like flowering and grain filling.
The second aspect about water use relates to evaporation of moisture from the soil.
Once water has been applied to soil, either through irrigation or receiving rainfall, the next thing is that it will eventually evaporate.
However, the rate of evaporation depends on soil cover.
If the ground is covered by crop residues, this reduces the evaporation. Farmers should, therefore, desist from the practice of removing all crop residues through burning.
Crop residues in a field reduce runoff, thereby increase the time the water can percolate the soil to benefit your crops.
Once water has been received, the next step should always be to retain it in the soil.
This is only possible with a healthy soil, yes, I said healthy soil.
A healthy soil is deep, with a lot of organic matter.
This, therefore, means one should always minimise soil erosion, as this process washes away layers of the soil, leaving it shallow.
I have already discussed the issue of leaving crop residues on the soil. If possible, incorporate that residue into the soil to improve it.
A healthy soil is better able, not only to absorb the water, but most importantly, to keep it in the soil as well.
Intercropping can also be used to conserve moisture.
A situation where a farmer grows a tall crop like maize, intercropped with a legume like groundnuts or sugar beans will minimise moisture loss. While the tall crop will shield the lower one from pests and water damage, the latter will hold moisture in the soil for the benefit of the former.
However, this is usually practical for smallholder farmers, who grow crops on small pieces of land.
Crop rotation also helps in creating a healthy soil.
Nowadays, most farmers have a tendency of growing maize on the same piece of land, year in, year out.
Different crops have different root systems. Some have roots that are able to penetrate the soil and get moisture from lower levels, and others have shallow roots that are only able to get moisture from the top levels.
Rotating crops with different root systems will, therefore, improve the soil.
Alternating a cereal with a legume will also mean one crop leaves desired nutrients for the next crop.
Farmers should also consider staggering their planting dates with the hope that some crops will be lucky to receive rains at critical stages and reach maturity.
Most farmers continue to use their pieces of land without any conservation works.
Conservation works include storm drains and contours that slowly drain excess water from the fields onto waterways.
Without these conservation works, after a downpour, the water runs off the fields very quickly, as there is nothing to stop it.
Therefore, ask yourself if your land has adequate conservation works.
If unsure, contact your extension officer and ask them to peg some for you.
You still have enough time to have them pegged and for you to put them in place before the onset of the rains.
Farmers should also consider water harvesting and storing water in a weir, where this is possible, especially where there are flat stone surfaces (ruware). Such surfaces promote fast runoff, and if possible, capture this water in either storage weirs or tanks.
Farmers can also harvest water from rooftops into storage tanks. They can then use drip irrigation systems, among others, to water their crops.
Obviously, this cannot be done at a large scale.
Farmers with small pieces of land can prepare tied ridges. Growing crops on the ridge is advantageous as they will have a deeper soil depth in which to develop their roots.
For crops like groundnuts, it actually helps in keeping aflatoxin levels low.
A farmer will tie and untie the ridges appropriately to conserve water and let it through when it is too much.
In a drought year, it is also critical that farmers practise good crop hygiene, by keeping their fields free of weeds.
Weeds compete with your crops for the little moisture that will be available. As such, it is crucial that farmers try as much as possible to use pre-emergent herbicides that kill the weeds before they germinate.
Allowing weeds to germinate and then try to control them later means they would already have taken quite a substantial amount of moisture from your crops, thereby delaying their growth and maturity.
Selection of the right crops, as well as varieties, is also crucial during drought years.
Most maize farmers would want to grow the long-season varieties as they obviously give a higher yield potential, but in drought years, that is risky.
Only use long-season varieties if you can either establish them early through irrigation or have the capacity to prolong the end of the season, again through irrigation.
When a long-season variety fails to get enough moisture, the yield loss is much more severe than with a short-season variety.
Therefore, please, find time to consult your extension officer or seed company representative to select crop varieties that suit your area and are drought-tolerant.
In most cases, a farmer who is unprepared for a worst-case scenario, gets affected the worst.
Those who will have looked ahead and sought solutions are more likely to be able to boldly face challenges brought about by climate change. Therefore, sit down and plan your next summer activities and options, whilst there is still time to put some of those options in place.
My parting shot is a Shona saying that runs: “Usazoyeuke bako mvura yanaya.”
The possibility of an El Niño-induced drought is real, so be ready to face it.
Peter Gambara is an agricultural economist and consultant based in Harare.
