underhaug two row automatic potato planter

Potato Planting Machine: how do they work?

If you had to plant a large field of potatoes you would most likely not make your drills with a hand shovel and set each seed potato by hand. This is where the potato planting machine comes in handy, it will set each seed to the required depth and cover it with soil. Perfect for potato growers with a large area to plant.

When was the potato planter invented?

The first mechanized potato planter was known as the “Bell planter” made by the Ferguson tractor company in the 1950s. It was designed to be attached to the Ferguson 3-point linkage on the back of the tractor. This machine consisted of a drill plow with three plow bodies which made two drills and a potato bin to hold the seed potatoes in that sat on top.

The Ferguson bell potato planter
The Ferguson “Bell Planter”

There was space for two men to sit – one on each side, where they would drop a seed potato down a pipe into the soil each time the land wheel would ring the bell. The plow bodies would then cover the seed potatoes with soil forming two uniform drills behind the planter.

The bell kept the spacing between each seed potato the same on both sides. Because it was land-driven it didn’t matter if the driver went slightly faster or slower – the bell got faster or slower accordingly.

How were potatoes planted prior to the potato planting machine?

Prior to the Ferguson planter, potatoes were planted by half forming two drills using a drill plow that lightly touched the surface of the soil. The potatoes were then placed by hand onto the half-formed drills. When the potatoes were all placed the drill plow came up the drill forming the full drill and covering the seed potato with the desired amount of soil.

This way of planting was backbreaking for the men and women who did it. They usually had a cloth bag/shawl filled with seed potatoes which they carried up and down the drills, and remained stooped placing them every 12″ to 14″ apart for the full length of the drill or until they ran out of seed potatoes.

How do modern potato planters work?

Modern potato planters work much the same way as old potato planters. They have a hopper to hold the seed potatoes to be planted in, these seed potatoes are then fed at regular intervals (depending on your chosen seed spacing) to a chute which goes down to the cultivated soil. Following behind are the drill plows or soil forming hood which covers the seed potatoes with the desired depth of soil.

Adding fertilizer to the soil

When potato planters first emerged they would have a small fertilizer bin in front of the seed potato hopper. This fed metered fertilizer directly to the chute where the seed potato was dropped down. This design of building the fertilizer bin onto the potato planter was later scrapped in favour of the fertilizer having its own hopper fitted to the front of the tractor.

Problems arose on the old planters if the grower decided to add a lot of fertilizer at planting. The close proximity to the seed potato meant the harsh chemicals in the fertilizer would burn and damage the seed potato.

The other reason to move the fertilizer to a big hopper on the front of the tractor was so it could be filled using big 1/2 ton bags of fertilizer – which was previously inconvenient due to the small size and location of the fertilizer bins on the planter.

Types of potato planters for tractors

Potato planters are classified into three different types. Manual, semi-automatic and automatic planters.

Manual potato planters

Manual potato planters are those in which the operator must manually pick up the seed potato by hand from a holding bin and place it into a chute that has access to the soil. The Ferguson Bell Planter is a manual potato planter.

Semi-automatic planters

Semi-automatic potato planters are similar to manual planters as they still require a person to be present during the planting operation. The difference is that the potatoes are placed into a mechanically driven wheel, as the wheel turns it delivers the potato to the chute to the soil.

The Underhaug semi-automatic potato planter
The Underhaug semi-automatic potato planter

The main purpose of the person who is overseeing their planting station is to make sure the mechanically driven wheel has always got a seed potato in its slot – otherwise, there will be a miss in the row of potatoes.

Automatic planters

The third type of planter and the one which is most in use today is the automatic planter. The automatic planter can take the seed potatoes from the holding bin by itself and deposit it down the delivery chute onto the soil without the need for an operator to be present on the planter machine.

a modern cup type potato planter by Grimme
A modern automatic cup-type planter by Grimme

Automatic planters reduce the labor to operate a potato planter from 3 people to just 1 – the tractor driver. Because the tractor driver doesn’t need to wait for someone to physically place the potato he can drive much faster than if he was using a manual or semi-automatic planter.

Belt planters and cup planters

There are two types of automatic planters available today. Belt planters and cup planters. As new belt planters increase planting speeds further, they are getting new customers, says Farmers Weekly.

Belt planters work by delivering the seed potato along a series of rubber belts before depositing them in the ground. Belt planters can travel at faster speeds at planting (nearly twice the speed of a cup planter) but this comes at a price. The accuracy of the belt planter is not as good as cup planters. A belt planter can handle more odd-shaped and sized potatoes than a cup planter can.

Inside the hopper of a standen belt type potato planter
Inside the feed hopper of a Standen belt-type potato planter.

Cup planters are known to be used at lower speeds than belt planters, and the cups can damage seed potato buds. The upside of the cup planter is that it is more accurate at spacing the seed. Although it seems the belt planter is better, the major downside comes when planting on sloping fields. The belt planter struggles to cope with hills, the hopper delivery chamber overflows going downhill and can run empty going uphill. Seed potatoes can also roll off the belts on side lying ground.

Inside the feed hopper of a Grimme cup-type automatic potato planter
Inside the feed hopper of a Grimme cup-type automatic potato planter
  • Belt players can travel at faster speeds than cup planters.
  • Belt planters can handle uneven-sized and shaped seed better than cup planters.
  • Cup planters are more accurate at placing seed than belt planters.
  • Cup planters can work better on sloping fields than belt planters.

Modern agriculture rarely uses any other type of planter than automatic nowadays. The manual and semi-automatic are still useful labor-saving machines for those on homesteads or for those who grow a few potato drills for home use. These lower-output machines are becoming more collector items for vintage displays as their numbers continue to dwindle. If you have one don’t throw it out- it is a piece of history!