The drum seeder: sow rice faster, cheaper and in rows

Anyone who has walked through a Bangladeshi village during the boro or aman planting season knows the scene. Seedlings are pulled from the nursery bed and tied into bundles, carried on heads to the main field, and pushed into the mud one clump at a time by rows of workers bent double. It is back-breaking and slow, and it comes at exactly the moment when farm labour is hardest to find and wages are at their peak. Many farmers end up planting late, and late planting costs grain at harvest. One of the cheapest answers to the problem is a drum seeder: a light, hand-pulled machine of perforated drums on an axle that drops sprouted rice seed in straight rows as one person walks it across a puddled field.

Machinery is spreading steadily across farming in Bangladesh. Combine harvesters and mechanical rice transplanters get most of the attention, but they cost hundreds of thousands of taka. The drum seeder sits at the other end of the scale. It is inexpensive, needs no fuel and almost no maintenance, and yet it solves one of the most important jobs of the season: getting seed into the ground at the right time and in the right way. For a smallholder it is the cheapest step into mechanised farming there is.

A drum seeder is essentially a set of hollow drums mounted side by side on an axle. Each drum has rows of small holes punched around its circumference at fixed intervals. A wheel sits at each end and a handle at the front. The drums are filled with pre-germinated seed, and as the machine is pulled across a puddled field the wheels turn the drums. With each revolution seed falls through the holes onto the mud in a line. The result is a field of straight, evenly spaced rows.

The idea was developed for rice. The International Rice Research Institute (IRRI) designed a manually operated drum-type row seeder for lowland paddy, and the Bangladesh Rice Research Institute (BRRI) later modified it to suit local soils and farming practice. BRRI's Rice Knowledge Bank calls the method direct wet seeding: instead of transplanting, sprouted seed is sown straight onto well-prepared puddled land.

Four-, six- and eight-row versions are common. A field report by the Agricultural Extension in South Asia (AESA) network in India describes an eight-row machine with a fibre body that needs little pulling force. In that design rows are 20 centimetres apart, and seed clumps within a row are 5 to 8 centimetres apart.

Conventional rice farming happens in two stages. Seedlings are raised in a nursery bed, then pulled at 20 to 40 days old and transplanted into the main field. Preparing and tending the nursery, uprooting, carrying and transplanting each need their own hands. The drum seeder cuts out that entire phase. Seed goes straight into the main field, sprouts there and grows there.

Pulling seedlings tears roots, and a transplanted plant needs several days to recover and put out new roots before it grows again. Direct-seeded rice avoids that shock. According to the AESA field report, drum-seeded rice matures 7 to 10 days earlier than transplanted rice. A crop that ripens a week or more sooner leaves more time for the next crop, and a better chance of beating an early flood or storm to the harvest.

The biggest gain is in time and labour. Sowing with a drum seeder takes roughly half the time of the old methods and saves up to 30 per cent of the labour. For fast, even sowing the machine is close to ideal.

The AESA report puts figures on it from the field: one person pulling a drum seeder can sow a hectare, around seven and a half bigha, in five to six hours. Transplanting the same area by hand takes three to four days and 30 to 40 workers; with the drum seeder three people are enough. BRRI's Rice Knowledge Bank says the technology helps farmers cope with labour shortages, lowers costs and can yield 10 to 15 per cent more than transplanted rice.

Those numbers matter more in Bangladesh every year. Migration to cities, jobs in garment factories and work overseas have thinned the rural labour force. At the height of the planting season a day's wage in many areas is beyond what a small farmer can comfortably pay. A machine that does three days' work in a morning hands back both time and money.

Broadcasting seed by hand leaves it piled up in some places and missing in others. Where it is crowded, plants compete for light, water and nutrients; where it is sparse, weeds move in. A drum seeder drops the right amount at the right spacing, so less seed is wasted and the seed that is sown grows better.

The difference in seed use is striking. The AESA report gives a seed rate of 25 to 37.5 kilograms per hectare with the drum seeder, against about 75 kilograms for traditional methods. Published research on BRRI's modified seeder has cited a rate of about 60 kilograms per hectare. The right rate depends on the variety, the size of the grain and how full the drums are. For farmers who buy costly certified or hybrid seed, the saving shows up directly in cash.

Evenly spaced plants share nutrients evenly. Air moves more freely around the base of each hill and sunlight reaches further down. Disease pressure eases, and both yield and grain quality rise.

When the plant population in a field is right, fertiliser, water and pesticide are not wasted. Seed placed properly to suit the soil means less of all three is needed. The cost of a nursery bed, of pulling seedlings and of transplanting labour disappears. Taken together, the cost of production falls and profit rises.

In the AESA field comparison, drum seeding cut costs by 9,000 to 14,000 Indian rupees per hectare and produced higher net returns than transplanting. Those exact figures will not carry over to a Bangladeshi field, where wages, seed prices and soils differ. The direction is the same, though: whatever is saved on labour and seed stays in the farmer's pocket.

Rice is where the drum seeder is used most, but the machine is versatile. Models are available for wheat, jute, mustard and other small-seeded crops. Sowing in rows makes later weeding, irrigation and harvesting more orderly. It works on small plots and large farms alike: on a small field one farmer can pull it alone, and on a larger holding several machines can run side by side to cover a lot of ground quickly.

Each crop does need the right hole size. Mustard seed in a drum built for rice will pour through far too fast. Before buying, it is worth checking which crop a machine is designed for and whether its holes can be changed or blocked.

A drum seeder does not sow dry seed; it sows sprouted seed. If the seed is badly prepared, no machine will make up for it. IRRI's Rice Knowledge Bank advice runs roughly as follows:

• Select good, plump, disease-free seed. Float it in water and skim off the light and empty grains.
• Soak the seed in clean water for 24 hours.
• Drain it, cover it with a jute sack or cloth and leave it for another 24 hours. In that time a root 2 to 3 millimetres long will emerge.
• Before sowing, spread the sprouted seed in the shade for 10 to 15 minutes so the grains separate and do not stick together.
• Do not fill the drums to the top. Research has found that filling them to about a quarter of capacity gives the most suitable seed rate.

If the sprouts grow too long they break against the inside of the drum and clog the holes, so the seed should not be left covered for much more than 24 hours. Short-rooted seed flows best.

Half of a drum seeder's success depends on the field. The land has to be ploughed and puddled well, then levelled as evenly as possible with a ladder or leveller. Low spots collect water and the seed rots; high spots dry out and the seedlings die.

Standing water is drained off before sowing. The soil should be soft mud with no water on top. Narrow channels cut around the edge and through the middle of the field let rain run off quickly. No irrigation is given for two to three days after sowing so that roots can anchor. After that the water level is raised gradually as the seedlings grow, without ever drowning them completely. The AESA report recommends light irrigation every two to three days until panicle initiation, 2 to 3 centimetres of standing water after that, and stopping irrigation 10 days before harvest.

Once seed and land are ready, the real work is pulling the machine. The first row matters most, because every row after it follows its line. Many farmers stretch a rope tight from one bund to the other to mark the direction of the first pass, then use the wheel track beside the machine to guide each pass after that.

The machine should be pulled at a steady walking pace, neither rushed nor halting. Jerky pulling drops too much seed in some places and too little in others. At the end of the field it is best to lift the machine slightly while turning so that seed does not pour out in one heap. Every so often the drums need checking, to see whether seed is running low and whether any holes have clogged with mud or sprouts. Keeping the drums at about a quarter full keeps the seeding rate roughly constant.

Within a week of sowing, it pays to walk the field again. Where seed has failed and gaps have opened, a few sprouted seeds can be dropped in by hand, or seedlings moved from a crowded patch nearby. That keeps the plant population even across the field.

Set against a mechanical rice transplanter, the drum seeder's advantages become clearer still. A transplanter needs seedlings grown in special trays or mat nurseries, costs far more, burns fuel and needs a skilled operator. A drum seeder needs no nursery at all, and any farmer who has watched it used once can run it.

Much of the drum seeder's appeal to farmers comes from the way it is built:

• A plain design: it is straightforward to run and to maintain, and needs little more than a wash and dry after use.
• Durable construction: plastic or fibre drums on a metal axle last for years and stand up to rough handling.
• Portable: it is light enough to carry on a shoulder or a van from one field to the next.
• Next to no fuel cost: a hand-pulled machine burns no diesel at all.

Because it is cheap, several farmers can buy one together and take turns. In many areas farmer groups and cooperatives share machines in exactly this way.

Like any technology, the drum seeder has weak points, and knowing them in advance avoids losses.

The first is weeds. Transplanted seedlings enter the field several weeks old, and standing water keeps weeds down. In direct seeding the rice and the weeds germinate together, so competition is fiercer. IRRI warns that weeds are a very serious problem in both wet and dry direct seeding, and delays in land preparation make them worse. This is where the drum seeder's straight rows pay off. A push weeder or rotary weeder can be run between the rows, and hand weeding goes faster too. Where needed, an approved herbicide can be used on the advice of the local agriculture officer.

The second is snails, rats and birds. Seed sown on wet ground and tender seedlings are favourite food for snails, and birds and rats can strip patches of a field bare. Keeping watch for the first few days after sowing, keeping water in the drainage channels rather than on the field, and scaring birds away all help.

The third is weather. Heavy rain soon after sowing can wash seed away or leave it to rot in ponded water. Picking a sowing day with an eye on the forecast is sensible. In low-lying, waterlogged land with no way to drain it, the drum seeder does not do well.

The state has also been pushing farming towards machines. The Department of Agricultural Extension (DAE) ran a Tk 3,020 crore project, Mechanisation of Agriculture through Integrated Management, from July 2020 to 2025. Under it farmers received subsidies of up to 50 per cent on the price of machinery, rising to 70 per cent in the haor wetlands. The eligible list included combine harvesters, reapers, rice transplanters, seeders and bed planters, power threshers and more, although most of the money went to large machines, above all combine harvesters.

A drum seeder is different. It needs no large investment and no wait for a subsidy. Farmers who want to know where one can be bought locally, or whether training and demonstration plots are available, can ask at the upazila agriculture office or a BRRI regional station.

Taken together, the case for using a drum seeder comes down to this:

• It ensures correct spacing, so the field's fertility is used to the full.
• It cuts waste of seed, fertiliser and pesticide.
• By skipping the nursery and transplanting it brings the crop to maturity sooner, so the harvest comes in earlier.
• It is environmentally sound: it burns no fuel, needs less fertiliser and pesticide, and protects the health of the soil.

That last point has a practical side. Less fertiliser and pesticide means less of both washing into ponds and canals, and less harm to fish and to the insects that help farmers. And with a hand-pulled machine there is no diesel to burn.

The drum seeder is not just easing farmers' workload; it is widening their margins. Technology-driven farming is making agriculture more modern, profitable and sustainable, and this hand-pulled machine is one of the most affordable examples of that change. As a modern way to get more grain for less money, it is within reach of the smallest farmer.

Buying the machine is only the beginning. Trying it first on a small plot for one season, learning to sprout seed properly by hand, levelling the land and planning weed control in advance are what will decide the result. A farmer who follows those steps may well find neighbours stopping at the edge of the field, looking at the neat green rows, and asking where the machine came from.

There is also much to learn from those already using drum seeders. Field days and demonstration plots run by upazila agriculture offices show which varieties, seasons and types of land suit the machine best. However plain the technology, adapting it to the realities of one's own field remains the farmer's job. Talking to other farmers on those days reveals where they went wrong in their first season, which fields suffered most from snails, and which varieties flowed best from the drums. None of that is written in any manual, yet for a newcomer it is worth a great deal. A technology truly takes root in a village when one farmer's success persuades the neighbour to pick up the handle too.

Photo: Pre-germinated paddy seed, the kind a drum seeder sows, Prajna Prabhu / Wikimedia Commons (CC BY-SA 4.0)