For a long time now, the crop yield per unit area of production in Uganda has been on the decline. The main contributing biophysical factors are inherent soil fertility particularly nitrogen and potassium deficiencies, exacerbated by soil fertility depletion.

Loss of soil nutrients through crop harvests as well as soil erosion is on the increase in many parts of the country. Many farmers are unaware of the losses, so they are doing nothing about it.

It is hard to sustain food production without using fertilisers. Studies around Lake Victoria basin, Bunyoro and eastern Uganda have shown that the soils can no longer sustain crops to meet challenges of a growing population. This has prompted soil experts in Uganda to highlight soil nutrients depletion as a crisis.

Although soil testing services are available in the country, few farmers in Uganda carry out soil testing on their land; yet doing so would help them a lot in deciding what crops to grow or fertilisers to apply.

The general assumption is that soil sampling is such a costly exercise that only large-scale commercial farmers can afford it. This is of course wrong. Actually it can be more costly for a farmer to start growing crops without first testing the soils.

Currently, about 3,000-5,000 soil samples submit[1]ted by farmers and researchers are analysed annually by the Soils and Soil fertility Management Unit. The unit is based at the Na[1]tional Agricultural Research Laboratories (NARL) at Kawanda National Agricultural Research Organisation.

Farmers have to collect soil samples from their farms and deliver them to Kawanda for testing. However, according to the soil experts at Kawanda, few farmers bother to seek advice on soil management from them. Different soil types are suitable for different plants. By getting to know the right type of soils, farmers will plant the right crops resulting into bumper harvests.

Why is soil testing necessary?

• Soil maps are used in planning and decision making both at the national and local administration level.
• They are used to determine location or relocation of farms, plantations, forests, industries, buildings and many other developments.
• Soils maps are used to develop other maps that will be useful to farmers.
• Besides determining soil suitability for different agricultural enterprises, the maps can help in preventing destructive happenings such as soil erosion.

Pawpaw wine

A research report by NaCRRI shows that scientists have made significant strides in other value-added products, including pawpaw wine, meat tenderiser, and solar dried pawpaw chips.

“We have also successfully substituted synthetic sugar with pawpaw purée by 100% and 50% in the making of confectioneries such as mandazi and cakes respectively. Through making wine, we have been able to reduce post-harvest losses by almost 100% since only the non-marketable fruits are used,” the report adds.

Skin lightening

Dr Ephraim Nuwamanya, a biochemist working with the NaCRRI-based nutrition and bioanalytical laboratory, said pawpaw has got loads of papain, an enzyme that breaks down proteins.

He said the enzyme has the ability to digest off the used-up skin and, thus, allowing the new skin to grow, which is lighter in complexion.

Nuwamanya said pawpaw, especially the seeds, have higher levels of antioxidants compared to even tea.

“Pawpaw contains antioxidants such as vitamin C and flavonoids that reduce the concentration of cholesterol, a bad fat, in the body. The antioxidants increase the metabolism of cholesterol and, thus, reducing its concentration in the body. This gives chance to the regeneration of new useful muscle in the body,” he said.

Mukiibi said farmers are the first direct beneficiaries of the innovations.

He said much as the weight loss beverage and skin lightening products have been developed from pawpaw, they await biochemical profiling to ascertain the exact proportions of the nutritive compounds therein, as well as official certification before they can be availed on the market.

Early last year, the Uganda National Bureau of Standards (UNBS) banned 177 cosmetics because they contained traces of Hydroquinone, a depigmenting agent used to lighten areas of darkened skin, as well as mercury, a heavy and dangerous metal.

UNBS said these products on long-term use could lead to skin discolouration, kidney and skin cancer as well as liver damage.

However, Dr Ogwang Edward, an expert working with the Skin Specialist’s Clinic in Wandegeya, Kampala, said pawpaw has got a lot of antioxidants such as vitamin C that are very vital for skin nourishment.

He said organic cosmetics are a game-changer but cautioned the public against the use of any skin products before rigorous tests have been carried out to ascertain their safety.

Fruit growing in Uganda

Uganda is the second-largest producer of fresh fruits and vegetables in sub-Saharan Africa, after Nigeria, producing about 5.3 million tonnes per year, according to the Food and Agriculture Organisation (FAO).

Experts estimate the productivity of pawpaw in the country at 10 tonnes per hectare and planted under 2,000 hectares of land.

Market reports reveal that Uganda earns about $0.48m annually from the export of pawpaw.

However, research reports indicate that fruit and vegetable post-harvest losses in the sub-Saharan region range from 30% to 80%, depending on the crop.

This is mainly attributed to the limited skills in post-harvest management, leading to limited access, utilisation of the fruits and thus, contributing to significant levels of malnutrition and poverty in the region.

Therefore, reports make case for deliberate efforts to empower smallholder farmers and other stakeholders to process and add value to fruits to reduce poverty, hunger and malnutrition among the youth, women and children.

History of cashew nuts

Okilan says the crop was first introduced in Uganda in the 1970s by traders. However, due to the political instabilities at the time and the fact that the crop needs special care during the early period, the trees died out. It was reintroduced in the early 2000s by NARO and has since been grown by isolated farmers.

“This crop is very profitable to the extent that in Tanzania, for one to trade in cashew nuts must obtain the buying licence from the Cashew nut Board of Tanzania, and dispatch notes from any corporate union, among other requirements. So, we intend to promote its growth in Uganda such that we can also benefit from its revenue,” he says.

Dixon Kyaba Tukam, the executive director for Uganda Cashew nut Growers, an organisation that promotes its growth, says with the many dynamics that have changed in the farming and the environment evident with the unpredictable seasons, cashew nuts are the answer as it does not require much water.

“For a long time, we Uganda’s economy has been dependent on coffee but for the past years we have seen more crops emerging. Also, with the diseases and pests emerging, it is to our advantage that we introduce new cash crops that can supplement on the existing ones,” Tukam says.

He adds that with the diverse environment degradation effects resulting from cutting of trees, cashew nuts will help in mitigating the damages caused as they are trees with thick canopies yet can last many years.

HOW TO GROW CASHEW NUT TREES

Managing nursery bed

Okilan explains that when planting the cashew nut tree, the nursery is the beginning and the success of the farm. If the seedling gets any defaults from the nursery, it will affect the trees in the main garden and so will be on the harvest.

The area where you are going to set up the nursery bed is slanted such that there is no water-logging. Because they are delicate, keep off all the animals and possible destructive animals like goats, stray dogs and chick from your nursery bed

Should seeds be planted directly or be potted before planting?

Okilan says cashew nut seeds can be planted directly to the garden, but pre-germinating then is the best as you will have a 90% assurance of the viability of the seeds. Also, nursery bed helps to avoid the pests like lizards that eat the buds.

Here, first soak it into water for three days with each soaking session lasting three hours, but changing the water every day.

The shades should be temporary because when the seeds germinate, they should be kept for only two weeks because if they over stay you will be inviting fungal diseases. Also, there should be no trees around to bring shades.

Does one need too much water to grow cashew nuts?

You need to have a source of water, preferably an open source but if you are to use tap water, keep it in drums for 24 hours before use to reduce the effect of the chemicals used to treat the water. Overall, a cashew nut tree needs less water compared to, for example, matooke or coffee.

When do I transplant the seedlings?

Seedlings must be transplanted within three months because if they over stay, they will coil and when you take them to the garden, they will survive but when they become big and heavy, they will break off. Also, when the taproot grows into the ground, it will force the coiled area to straighten and eventually breaks and the tree will dry out.

Alternatively, when the taproot grows down in the bed, you will cut yet it will never develop again. Cashew has a poor rooting system with lateral roots that do not go deep. Since you already cut the taproot, it will develop secondary roots which are also lateral. Therefore, when the tree grows and the canopy becomes heavy and the wind blows it will be swinging, breaking the roots and eventually dries out.

At the time of transportation to the garden, make sure there is enough moisture in the you nurse them three days to the date of transplanting. Ensure the seedling remains with the seed. Avoid immediate loading because the seedlings will start shrinking in the vehicle by the time you reach the destination a quatre is dead and when they overstay before they are planted, they will die.

Planting cashew nuts

Okilan explains that before getting the seedlings from the nursery bed, you must have cleared the area designated for planting. It should be flat and not water-logged.

“Peg the area in accordance to the spacing you choose from the three spacing types. One spacing optin is 6m x 6m if you do not want to intercrop, but this spacing is for a short time such that when the trees start spreading, you eliminate the middle trees such that you leave spaces of 12m x 12m which is the standard spacing. With this, an acre of land will remain with 27 trees,” he says.

The other spacing is 10m x 10m, but with this spacing, after 10-12 years, the trees will start meeting. But here, you only need to trim the end of the canopy. This is because, cashew nut trees do not fruit in areas with shades that cause low temperatures. They require high temperatures to flower, fruit and require less rain for the fruits to grow.

Dig a hole of 2ft wide and 2ft deep, separating the black soil about 6 inchs and the red aside. Get good matured soil and refill the hole completely leaving no depression and use the red soil to create some raised ground (a hill). Thereafter, place back the peg such that you plant into the line.

Patrick Joseph Okilan, a cashew farmer and expert with NARO, explaining how to manage a cashew nut nursery bed. (Photo by Herbert Musoke)

Okilan advises that while planting, do not use artificial fertilisers because it will make the trees grow so fast and fail to fruit. A tree that would have fruited at one-and-a-half years, will delay for another year. It is better to use matured soils and keep the garden free of weeds.

The trees need continuous feeding where you add manure every after 4-5 years of harvest if you are to get the best harvest the next year.

What diseases affect cashew nuts?

Okilan says the most devastating cashew nut diseases are powdery mildew, anthracnose and dieback.

“These are the major diseases for cashew but it affected by few infections. What is required is prompt action. The moment you sight a disease, react quickly because like for the case of powdery mildew, in one week it will have covered quarter of the tree and in three weeks, the entire tree will be infected,” he explains.

Cashew nut fruits

The market

Okilan, who is also one of the buyers of cashew nuts in Uganda, explains that a cashew tree will start to be harvested from at one-and-a-half or two years and for the first years you will be harvesting about 4kg. However, when it reaches 10-12 years, one can harvest up to 55kg a season and it has two seasons a year.

“Today, a kilogramme of unprocessed seeds goes for sh3,000 and the processed one goes for sh35,000. This means that from the 50kg, you will earn sh150,000 from unprocessed seeds and from the 27 trees in an acre you get sh8.1m. For the processed, a tree will give you sh875,000 and from an acre sh23m,” he says, adding that you can harvest for over 100 years.

Phoebe Mujabi, who runs Darlin Products in Nakasero, Kampala, says cashew nut is one of their ingredients, noting that the product has big potential in Uganda with value addition.

“We are importing the nuts from Tanzania and this is why our products look expensive,” she says. She adds that the Ugandan corporates have adopted eating the nuts, hence creating a ready market for them.

Cashew nut seeds

BENEFITS OF CASHEW NUTS

Kyaba explains that cashew nuts have several benefits, right from the leaves, stems, roots, sap, fruits and the apple. The tree is useful as explained below;

• Prevents cardiovascular diseases

Cashew contains oils with healthy fat, linked with a healthy heart. The nuts are free from cholesterol and also provide essential nutrients to boost the heart functioning.

• Prevention of cancer

One of the major benefits of eating cashew is that it reduces the risk of cancer. Proanthocyanins is a type of flavanol which stops tumour cells from growing in addition to copper, responsible for prevention of cancer.

• Weight loss

Cashew has good fats recommendable for a health body. The fat present in cashew nuts is responsible for growth of good cholesterol and reduction of the bad cholesterol. It gives a lot of energy and also keeps you satiated for a long time. Therefore, eat 3-4 cashew nuts every day for proper weight management.

• Cashew apple

All the parts of the cashew tree are important. For example, cashew apples can be used to make jam, wine and juice. If eaten while still raw, they help to cure a sore throat and also when fed to the animals, especially dairy cattle, one kilogramme will give you two extra litres of milk and the quality of milk will improve.

The shells are used as fuel in big factories. They also contain industrial oil used in lubricating high heating engines such as those of the aeroplane. The back is used for making ink and also the tree produces light timber suitable for making boats.

Farmers in Busoga region have embraced on-farm making of animal fertilisers as a strategy to cut costs, but also to generate better crops yields and income.

The technology has become a goldmine from which progressive farm enterprises, both in rural and urban areas, are thriving.

Observing that organic manure is cheaper and more effective than artificial fertilisers, the rural and urban farmers who interfaced with Harvest Money said the on-farm trend of generating fertilisers is paying off.

A 90kg bag of well-composted livestock manure in and around Kampala goes for sh36,000-plus, while in the rural setting, a 100kg bag costs between sh7,000 and sh10,000.

Vision Group’s Uganda’s Best Farmers from Busoga region are testimony that livestock waste is gold from which they bag “good” money.

One such farmer is Julius Bataamye, a 2017 winner, who has turned his chicken droppings, heifers’ and pigs’ dung into cash on his JB Farm Naminage, Kamuli district.

He has 5,500 pigs, 95 heifers and 15,000 chickens and 150 turkeys, whose waste accumulates on a daily basis.

Bataamye then packs the waste in 10kg, 15kg and 25kg bags, which he sells for sh2,500, 5,000 and sh10,000 respectively.

For the upcoming farmers that cannot afford the costs, Bataamye slashes the rates by half. At times, he donates the waste to active farmer groups in the bid to empower them.

Still in Kamuli district, Johnson Basangwa, a 2014 Vision Group’s Uganda’s Best Farmer, sells a 50-100kg bag of the chicken droppings at between sh5,000-sh10,000 each.

Each day, Basangwa’s JEKA Poultry Farm, which has over 35,000 layers, generates many bags of droppings, translating to weekly and monthly earnings.

In Ssaza zone in Kamuli town, Hamida Nabirye, a livestock farmer, also heaps the waste of his 10 heifers, attracting buyers after every four months.

She told Harvest Money that the innovation earns her sh150, 000 and sh250,000 every four months.

Most of his customers are practising rural and urban agriculture, featuring courtyard and backyard gardens of green vegetables, eggplant, cabbages, spinach, sukuma wiki etc.

Edward Malevu Kuremu, a farmer at Kitimbo Road in Kamuli town in Kamuli municipality, said he discovered that animal waste was gold during the Jinja Agricultural and Trade show six years ago.

The above testimonies are the few told stories on the benefits of accumulating livestock waste, a practice worth emulating.

The trend, according to the first deputy premier, Rebecca Kadaga, has gradually changed the face of farms, translating to higher crop yields and fixing food security.

Using modern technologies, including animal waste to enrich the weathered soils, Kadaga said farms featuring modern practices are now energised, the reason why the “importation” of matooke, which sued to be sourced from the western Uganda, has reduced.

What you need to know about animal waste manure

Peter Dhamuzungu, the principal science officer for chemical services in the science ministry, advises farmers on the advantages of collecting livestock waste for money.

Dhamuzungu, also the director of Busoga Seed Solutions, says organic fertilisers can be made from kitchen and farm waste, weeds, egg shells, vegetable peelings and dry leaves, among others.

Livestock waste is accumulated by heaping and covering it with raw tree twigs or wide leaves such as those of bananas.

Many farmers, Dhamuzungu explains, use raw livestock waste on their farms. But for good results, the waste should be left to decompose to ensure it cures fully.

The decomposition takes about three months before the waste is ready for use.

When it is fully cured, it supplies nutrients to the soil, translating to energized crop growth and yields on the farm. On the other hand, when not fully cured, it takes time to cure instead of enriching the soil.

Other types of manure include that obtained from decomposing waste from the farm, the compound and the kitchen.

This, Dhamuzungu explains, allows micro-organisms to come to the surface. The micro-organisms break down raw materials to cause decomposition.

Dr Fredrick Kabbale, the district production and marketing officer for Buyende, adds that on top of these, the farmer can use green materials, mostly nitrogen-rich plants such as lesbania and lucina, to make organic manure.

Through the decomposition time though, Dhamuzungu explains that the farmer needs to pour at least 3-4 litres of water every week to aid the process, especially if the mature-making process is not being done during the rainy season.

The ready compost features rotten matter void of excessive heat and a foul smell.

“You end up with a cleaner environment and your organic manure at no cost,” Dmamuzungu says.

Recycled manure technology

Recycled manure technology was introduced by KULIKA Uganda and Balimi Farmers Network International (BFI), both agro promoting organisations.

Moses Mpasa, a beneficiary of the training, is using the technology in Kamuli district.

This features the collecting of empty plastic bottles of mineral water, energy drinks, buveera or old clothes, which are set on fire.

“After combustion, leave the burnt product for a week and mix it with the soil to get recycled manure,” Mpasa says.

BANDERA chairman George Mpaata says the technology was proved not to affect human life, besides being environmentally friendly.

Biogas slurry

This is made from waste residues of the biogas system.

Jacob Kazindula Bamwise, the 2017 Vision Group’s Uganda’s Best Farmer, is bagging cash from biogas slurry.

“I scoop the waste from the tanks and squeeze out the big particles. I then pack it in five and 10-litre jerrycans for sale,” Kazindula, who learned the technology during the Netherlands Embassy sponsored trip, said.

A jerrycan cost sh5,000 and sh8,000 respectively.

The product, which is poured on the crop stalks, seeps down to enhance both growth and crop yields.

Vermin compost

This involves rearing red worms, which break down manure by feeding on green material.

“The worms are fed on specific plants to get particular nutrients from them,” Dhamuzungu, who rears the worms, says. “To get phosphorus, for example, the red worms are fed on Russian comfrey.”

After feeding them, water is poured over the worms to seep down the nutrients, into harvesting tanks.

Farmers then irrigate their crops with nutritious tea to make them thrive energetically.

Human fertiliser

Human urine mixed with wood ash is fertiliser for food crops, especially tomatoes, without introducing any risk of diseases to consumers.

Studies indicate that microbes are killed either as a result of storage conditions or pasteurisation.

Dhamuzungu says human urine is a good source of nitrogen and phosphorus for plants such as cucumber, maize, cabbage and eggplants.

“It can be an alternative to the artificial NPK. The approximate concentration ratio of NPK in urine is 20:14, which is comparable to commercial chemical fertiliser,” Dhamuzungu says.

Wood ash, which is rich in minerals, reduces the acidity of certain soils.

• Word of referral: You can get this by talking to fellow farmers and in the process, a good worker may be referred to you.
• Do not poach on workers from other farms because this has through experience caused disharmony among farmers.
• Prisoners: This is turning out to be a big resource for daily farm labour, however, this can only apply to farms that are located near prisons for easy access to the farm. Furthermore, while prisoners are effective labourers, they cannot manage your farm because they do not stay there.
• Hire a manager and allow them to source for a few workers: Some managers have got their own workers and when you hire a professional farm manager, he will come with them. But of course, a professional farm manager is relatively expensive. If you cannot hire a professional, then make sure you train your workers by sending them to similar farms or workshops.
• Look for raw village workers, where the farm is located or further. It is common to see workers from the South-West working on farms in the Central region. This is what most farmers do. However, after hiring these raw workers, then you need to train them into becoming understanding farming. You can do this by taking them to exhibitions or to other farms that are practising similar enterprises.

How to retain workers

After hiring them, one of the ways of keeping them on the farm is to make them feel part of the farm. You can achieve this by doing the following;

• Share your farm vision with them: This will make them ‘human’ workers, rather than robots since they will be working on a clear vision. Tell them the objectives of the farm and how the workers fit in.
• Write an agreement and clear scope of work: This will help reduce cases of unfulfilled tasks since each worker knows what they are supposed to do.
• Take time to know and understand your people: For example, if you are hiring from a community that is not yours, learn a few things about the culture and behaviour of that community.
• Understand that each person has a weakness and strengths. So, make sure that you build on these to make your workers effective.
• Refer to people by name not position: We all value individuality; this is an age-old tactic that is always rewarded with loyalty. When you call a worker by their name, they know you care about them and this improves confidence and morale on the farm.
• Build a conducive environment for them: This includes housing and sanitation facilities, for example. Farmworkers must not always stay in funny grass-thatched houses without toilets. Set up entertainment too. For example, there are farm owners who even bought TV sets for the workers in order to stop them from going out of the farm to watch football. These look like expensive ventures, but they help keep workers on the farm.

.Allowing wives or husbands of the workers to either visit or stay at the farm. This may look disruptive in the short run, however, when you look at it further, it is actually less disruptive than a farmworker who wants to leave the farm in order to go and visit his or her spouse. In many cases, these spouses have turned into extra unpaid workers on the farm.

• Accept and value feedback from workers, as long as it is geared towards building the farm.
• As a person, you must also have passion and enthusiasm for your farm and the workers will definitely follow your passion.
• Listen, accept mistakes, but also encourage openness among workers
• Carry out a constructive disciplinary process and never show sides in case of an alternation among your workers.

When they perform well, make sure that you praise them. If you give them tasks, evaluate them regularly to see if they are meeting these tasks.

During site selection, avoid the following;

• Waterlogged areas because beans don’t tolerate waterlogged places.
• Very sandy soils.
• Soils that are compacted (clay) and too alkaline.

Soil Testing

It is essential to assess soil health before any soil management operations are implemented. Constraints such as soil acidity and soil nutrient deficiency can lead to significant reductions of crop yields. The soil pH and nutrients levels can be determined by conventional soil analysis in addition to observation methods of crops growing in the field.

Soil testing is an essential crop management tool that enables one to;

• Determine acidity and alkalinity levels of soil (pH).
• Identify any soil nutrient deficiencies.
• Estimate optimum fertilizer requirements for target yields.
• Estimate the optimum cost of fertilizer needed and the returns.

Timing of land preparation

• The timing of land preparation is extremely important.
• Land preparation should begin either at the end of the harvesting period or at least 3 weeks (21 days) before planting to allow breakdown of organic matter.
• Land should be ploughed at least twice in some cases followed with harrowing to obtain a fine seedbed.
• Where the field has a known history of bean pests such as pod borers, bean fly and beetles, complement ploughing with harrowing to kill the surviving eggs, pupae and adult pests.
• If the site is very bushy, first clear land by slashing down all plant parts and leave them on the ground, or plough in the plant residues using appropriate equipment.
• This will help soil to conserve moisture; improve the water-retention capacity, water-infiltration capacity and increase soil fertility.
• If the field was previously covered with weeds like Amaranthus spp, which produce a lot of seeds, then the land needs to be prepared early in the season.
• This will encourage most of the weed seeds to germinate as soon as the soil gets any moisture.
• The field can then be lightly tilled down or sprayed with non-selective herbicides (glyphosates) before beans are planted; very shallow cultivation is needed, only along the topsoil, to remove the germinating weeds.