The Sunday Mail
Peter Gambara
The 21st Annual Southern Africa Regional Climate Outlook Forum (SARCOF-21) was held in Gaborone, Botswana, last month where a consensus outlook for the 2017 — 2018 rainfall season over the SADC region was presented.
The forecast had been mistakenly taken to mean the next rainy season will be a drought one, thereby causing unnecessary panic among farmers and policy makers.
In this article, I will try to explain what the forecast means in simple terms and what strategies farmers can adopt to cope with a normal to below normal rainfall season.
The report covers the whole SADC region that includes Angola, Botswana, DRC, Lesotho, Malawi, Mauritius, Madagascar, Mozambique, Namibia, Seychelles, Swaziland, Tanzania, Zambia and Zimbabwe.
It, however, divides the SADC region into 11 different zones. Zone 1 covers Northern Democratic Republic of Congo (DRC).
Zone 2 covers northern Tanzania while Zone 3 covers northern Mozambique, southern Tanzania, northern Malawi, northern most Zambia, the bulk of DRC and north-western half of Angola.
Zone 4 covers Central Mozambique, southern Malawi, northern half of Zimbabwe, most of Zambia, southern most DRC, south-eastern half of Angola, bulk of Namibia, western half of Botswana, most of central and western parts of South Africa and western parts of Lesotho.
Zone 5 covers extreme south-western Zambia, Caprivi area, south-eastern most Angola, south-eastern half of Zimbabwe, eastern half of Botswana, most of northern South Africa, eastern Lesotho, Swaziland, and southern Mozambique.
Zone 6 covers south-westernmost Angola and western coastal areas of Namibia and South Africa. Zone 7 is western Madagascar whilst Zone 8 is eastern Madagascar.
Zone 9 is southern Madagascar, zone 10 is Mauritius and finally Zone 11 is Seychelles. The report also presents the report over four times three-monthly periods that overlap and these are October-November -December; followed by November-December-January; the third period is December-January-February and the fourth period is January-February-March.
It is obvious that the zones that concern us as a country are only Zones 4 and 5. The report says during the first period, that is October to December; Zone 4 faces increased chances of normal to below-normal rainfall whilst Zone 5 faces increased chances of normal to above-normal rainfall.
During the second period, from November to January, both Zone 4 and Zone 5 face increased chances of normal to above-normal rainfall.
During the third forecast period — December to February — Zone 4 faces increased chances of normal to above-normal rainfall, whilst Zone 5 faces increased chances of normal to below-normal rainfall.
In the fourth forecast period — January to March — both Zone 4 and Zone 5 face increased chances of normal to above-normal rainfall.
It is clear from this prediction that the only areas that are likely to face normal to below normal rainfall are Zone 4 during the first period, which is October to December and Zone 5 during the December to February period.
The rest of the areas in Zimbabwe face increased chances of normal to above normal rainfall through that forecast period.
On August 28, our Meteorological Services Department released its 2017-18 Seasonal Rainfall Forecast for Zimbabwe.
They indicated in that report that the Sadc report covers large areas and is therefore not likely to “fully account for all factors that influence national climate variability”.
Instead of using the four times three monthly overlapping periods, the MET report uses just two times three monthly periods — October-November-December and January-February-March. They also briefly explained the El Nino and La Nina effects to our region.
A rainfall season that follows an El Nino has a high probability of being a dry one, while a season following a La Nina is highly likely to be very wet.
These El Nino and La Nina events occur every four tosven years in an alternating sequence.
The 2015 to 2016 season followed an El Nino whilst this past 2016-17 season followed a La Nina.
The MET office also divides the country into three zones with Region I covering Harare, much of Mashonaland East, Mashonaland West, Mashonaland Central, north-eastern parts of Midlands and most of Manicaland.
This zone has increased chances of receiving normal to above normal rainfall during the October-November-December period and normal to above normal rainfall during the January-February-March period.
The boundaries for the three zones for first and second periods do change very slightly though.
Region II covers the greater part of Matabeleland North, parts of Midlands and parts of Mashonaland West.
This zone has high chances of receiving normal to below normal rainfall during the first period and normal to above normal rainfall during the second period.
Region III, which covers Masvingo, the bulk of Midlands, the extreme southern parts of Manicaland and the bulk of Matabeleland South has high chances of receiving normal to below normal rainfall during the first period and normal to above normal rainfall during the second period. I would say looking at both forecasts, there is no need to panic here.
Recently, Agritex officials who are tasked with registering farmers for the Command Agriculture programme were instructed to prioritise farmers with access to irrigation facilities.
Government had previously indicated that it was looking to contract at least 350 000 hectares of land for Command Maize production and an additional 60 000 hectares for soyabeans, bringing the total requirement to 410 000 hectares for 2017-18 season.
However, should Government only contract those with irrigation facilities, then the total contracted area is unlikely to surpass 220 000 hectares, which is the total irrigable area in the country.
To be able to fully comprehend the matrices of the rainfall season in Zimbabwe, one should also be familiar with our agro-ecological zones.
Zimbabwe is divided into five agro-ecological regions, known as natural regions based on the rainfall regime, soil quality and vegetation, among other factors.
I will dwell on the classification based mainly on rainfall.
Maize production requires around 600mm of rainfall per year and based on the above classification, all farmers in Natural Region (NR) I to III should ideally grow maize without much challenge from inadequate rainfall.
However, as highlighted above, most communal areas fall into NR III and NR IV and maize being a staple food, they have no option but to grow maize.
The other crops that are suited to these regions, that is sorghum, rapoko and millet yield very low per hectare and tend to be labour intensive in growing and processing them into food.
Farmers in these areas are therefore tempted to grow maize year after year.
Most of the farmers who are contracted to grow maize under the Command Agriculture programme are located in NR I to NR II and therefore combining the Sadc 2017-18 rainfall forecast, the MET Office forecast and the agro-ecological classification, these farmers should receive normal to above normal rainfall next season and can safely grow maize.
The second part of my article seeks to look at what farmers should do in preparation of a season that has the potential to receive normal to below normal rainfall season. Those farmers who have access to irrigation facilities should endeavour to establish part of their maize crop early with the aid of the irrigation.
These farmers can start establishing their crops this September and will need to supplement and irrigate the crops until the more reliable rainfall starts falling around end of October or beginning of November. Whilst the country received a lot of rainfall this past season, many farmers do not have storage dams on their farms and therefore could not store the abundant water from the rains.
For some, their only source of water will be a river, well or borehole, that might not yield a lot of water.
These farmers can still “water plant” with water. With this technique, farmers prepare their lands for planting and then open up furrows or holes to plant the maize. They can then use water pumps to apply at least a litre of water per planting station. It also helps if the maize has been socked for a minimum 48 hours.
However, the fact that the seed will have been soaked means farmers cannot use planters. A combination of the socking and the water applied per planting station should be sufficient to germinate the maize. Farmers will then need to occasionally irrigate the crop as needed (normally once a week) until the rains start falling.
Farmers without enough water to irrigate the germinated maize until the rain come should delay this water planting so that their maize only germinates maximum three weeks before the onset of rains. Maize can withstand two to three weeks of moisture stress quite well.
Those who do not have access to planting water should not despair.
They can also prepare their lands for planting, but will only go as far as opening up the planting furrows or holes and then wait for the first rains to fall.
As soon as they receive the first effective rains, they will then proceed to sock their seed and plant as indicated above.
Farmers who intend to put large areas under maize also fall into this category, they should adequately prepare in advance so that come the first rains, they can move in and plant with their planters.
If enough moisture is available in the soil, maize will normally germinate in about seven days.
As long as farmers have received effective rains and have correctly placed the seed in the soil, the maize will germinate.
Farmers are therefore urged to ensure that they do not plant the seed too deep and that they place the seed at a safe distance from the fertiliser, especially if they do not have irrigation facilities or if they are planting in dry soil.
Those farmers who use ploughs to open up furrows to plant seed end up placing the seed too deep to the extent that it fails to germinate, even with effective rains.
If the seed is also too close to the surface, it also risks being devoured by birds or failing to have enough soil to cover it and therefore it dries up quickly.
A correctly calibrated planter will place the seed deep enough so that if one gets just a few showers, the water does not get to the seed.
It is dangerous for a seed to get enough moisture for it to start germinating and then the moisture dries up, the seed will die. However, if the seed is placed at a depth where only good rains will reach it, it will germinate with the first effective rains. If one has irrigation facilities, they should ensure that the field is moist enough during the seven days for the seed to germinate.
However, some soils have a capping effect and if it dries before the seed germinates, the germinating seed will fail to penetrate the top soil and will simply curl back into the soil and rot.
It is essential therefore that the soil has enough moist within the seven days that the seed is germinating.
Farmers should also resist planting seed into a soil that is almost dry or half-moist as the seed will start germinating and die as the moisture dries up.
If one has to rely on rainfall to germinate the maize, make sure your planted maize gets adequate rainfall by making sure the seed is already in the soil before the rains fall or one is able to move in immediately after a heavy downpour. That is normally difficult with red clay soils.
The most important aspect remains — being early. Farmers should strive to plant the majority of their crops early so that they can take advantage of all the rains that will fall, enjoy a longer growing period and hence achieve higher yields.
The money in farming comes from high yields. Let me end by wishing all farmers a prosperous 2017-18 summer season with adequate rainfall to enable you to achieve those good yields.
Let us continue to pray so that the Almighty gives us normal to above normal rainfall once more.
Peter Gambara is an agricultural economist and consultant based in Harare.
