Prof J Derera and Wendy Madzura Correspondents
The concept of growing a maize crop for sale as fresh cobs on the market, before the cobs reach the hard dough stage is referred to as green mealies or “gocha” maize production.

This cropping venture enhances cash flows at the farm or household levels as income streams are increased, resulting in effective land utilisation.

Green mealie production creates employment on the farm and in urban markets where the green mealies are in high demand throughout the year.

Nutritionally, green maize provide immense health benefits owing to the high fibre content in green mealies as opposed to the processed maize meal.

In this article, we discuss and illustrate how farmers could maximise return on investment (ROI) through variety selection and good agronomic practices.

Maximise return on investment

With farming becoming more and more of a formidable business, farmers are urged to consider profitability of any cropping venture before establishing the crop.

As a result, market analysis is crucial, because growers have to take market forces into account before entering the green maize business. Generally, there is high returns for every dollar which is invested in green mealies, very much more profitable than grain production if it is well timed.

A return of US$2 to US$3 or more for every dollar invested, under good agronomic practices (GAPs) shows that green maize production is viable.

The costs of production should be kept under US$800. The variable costs comprise seed, fertilisers, pesticides (insecticides and herbicides), irrigation and labour.

The aim is to harvest 3 500 dozens of green cobs per hectare and sale them for $1.50 to yield $5 250 per hectare.

A lower plant population would yield 3 000 dozens of green cobs resulting in a revenue of $4 500 per hectare, which is still profitable.

A delayed planting would result in a lower price of $1 per dozen which can reduce revenue to as low as $3 500, which is still profitable.

The crop lasts for about 100 to 110 days in the field. This allows the farmer to do at least two crops per year. This serves to illustrate that green mealies are indeed a lucrative cropping venture to consider, profitability margins are highest if the planting window is well-timed with a careful consideration of market forces of supply and demand.

Be the first one on the market, then bring a second and third batch of green mealies, of course with a declining margin, but still profitable.

Split planting is encouraged so that the crop will get past the hard dough stage before selling.

Build the profit

The yield matrix is hinged on the farmers’ ability to optimise on the essential elements of production. These include genetics, soils, weather and management.

There are a thousand reasons for low yields, but only two reasons for higher yields: variety choice and good agronomic practice!

Variety choice matters

The adoption of new, modern innovative seed technologies is the surest way to start the profit journey.

There are a wide range of varieties to choose from, varieties from different maturity groups both in the yellow and white maize categories.

In green mealies, variety selection is guided by the Value for Cultivation (agronomic potential) and Use (consumer or end-user potential) which is generally referred to as the VCU.

The preferred traits for a good green maize variety include a long and attractive cob with high number of grain rows. This determines cob size, so the larger the cob the better for consumers.

The number of kernels per cob is also crucial, such that a high kernel set is desired. A good kernel set is characterised by deep kernels which translates into a high shelling percentage.

A further property of green maize which affects market preference is the consumers’ desire for sweet and good roasting qualities of green mealies.

Green maize merchants prefer varieties that they can sell fresh for longer.

As a result, the grain dry down rate is a major section criterion. This affects the length of the milk dough stage and consequently the green mealie harvesting window.

Naturally growers want a long window for harvesting and selling and retailers and other merchants a long shelf-life.

The other essential properties of a good green maize crop is the ability to establish a uniform crop which is tolerant to diseases such as the maize streak virus, especially when the crop is grown in the irrigation schemes in winter.

The absence of other grasses puts the green maize crop under a tremendous pressure of the Cicadulina leaf hoppers which spreads the maize streak virus (MSV) disease.

Single cross hybrids would provide a nice uniform crop where the cobs can go for the same premium price on the market.

There are growers who may want to plant the green maize crop at once, but aiming to sell for a long period at a premium price.

In this case, it is advisable to plant varieties in different maturity groups to spread the selling window and increase profitability. The foregoing illustrates that Variety Choice Matters, hence farmers should choose wisely from a wide spread of varieties on the market.

Employ good agronomic practices (GAPs).

A fine-tilled land supports a good market produce. Land preparation is one of the important aspects of good agronomic practices.

Whether the farmer uses the conventional or conservation tillage, the main aim is to achieve a fine tilth in the seed placement zone (good seed to soil contact).

This maximises and promotes root penetration, aeration and water infiltration within the rooting zone.

However, sustainable methods of land preparation which include conservation agriculture in light of climate change is encouraged.

Seed dressing is key for the winter crop.

A case in point in green mealie production is the issue of using seed dressing at planting to manage the incidence of maize streak virus disease (MSV).

The MSV is common during the time when green mealie crops are established in winter. Signs of this disease include discontinuous white lines on the leaves of affected maize plants. The virus can have devastating effects such as wiping out the whole crop, affect rate of growth leading to stuntedness and reduction in yield potential.

Farmers should use insecticides that include imidacloprid whose common trade name is (Gaucho) as a seed dressing. Discussions with agrochemical companies are encouraged for registered seed dressing chemicals for the prevention of MSV.

When to plant

One question that sits on every farmer’s mind for any cropping venture is the timing of crop establishment.

For green mealie production, the secret to a higher return per dollar invested (ROI) lies in the ability to plant the crop before the onset of the rainy season.

In frost-free areas, such as the Lowveld and other frost-free pockets of the country the most lucrative crop is established in winter, provided water is available for irrigation.

Farmers in to frost-prone areas will establish green mealie crops immediately after the winter season. The end of July to early August window is the best for green mealie crop establishment. Unfortunately, farmers often tend to procrastinate.

This results in a late crop establishment which then coincides with the rainy season.

This will lead to profit reduction because the market would be flooded with cheaper maize from the dryland production. Late green maize crop establishment also affects the planting of the next crop with profound implications for yield and ROI for the crop.

Optimise plant population

At planting green mealies require the correct in-row and inter-row spacing to get the optimum plant population density. The optimum plant population in green mealie production is that which produces long attractive cobs that are sellable on the market.

As a result, farmers should aim to achieve a plant population of 40 000 to 48 000 plants per hectare depending on the variety.

To achieve this, farmers should use an inter-row spacing of 75cm to 90cm and an in-row spacing of 30cm to 25cm. Farmers should aim for harvesting 3 000 to 3 500 dozens of sellable green cobs per hectare to make their cropping venture profitable.

Fertility management for green mealie production is best guided by soil analysis results.

As a general guide farmers can use compound basal fertiliser at a rate of 300-400 kgha-1 the rate varies for different fertiliser formulation including blends.

For top dressing farmers can use 350 to 400 kgha-1 of ammonium nitrate (AN) or urea factoring in the soil type for split applications.

Foliar fertilisers are encouraged as boosters and to provide the trace elements that add on the quality of green mealies.

Weed management plays a pivotal role in crop management.

Poor weed control can result in 50 to 100 percent yield loss. Weeds compete with crops for moisture, nutrients and space resulting in reduced yields.

Farmers should aim to have a weed-free field for the first 6 to 8 weeks of the crop establishment. Effective herbicides use is based on weed spectrum, stage of control, rotation plan and herbicide cost.

Insect pest management is an important part of crop production.

Farmers should know the problematic insect pests and plan effective management before the establishment of the crop.

In green mealie production, as has been the case with maize production in recent years, Fall Armyworm (FAW) has been a huge menace in maize production with the potential to reduce yield levels significantly. Insect damage reduces the surface area for photosynthesis reducing growth rate.

Effective management of FAW lies in ability to conduct regular scouting and detect infestation before economic threshold levels are reached.

Other problematic insect pest of concern are white grubs, cutworms, fall armyworm and African stalk-borer.

To sum up, farmers should remember that green mealies is a maize crop whose harvesting comes early and should be managed carefully. All the good management practices that they employ in managing a maize crop for grain production should be employed in green mealie production.

Good Agronomic Practices are like the icing on the cake. They unlock the genetic potential of the exceptionally good genetics, paving way for high yields and increased productivity.

Good agronomic practices must take care of the following factors: soil type, soil fertility, weed, insect pest and disease control, weather, crop rotations and the general management.

Management of these factors works together in the attainment of a common goal of achieving profitability through increased yield and obtaining a premium price at the market.