Furrow irrigation is a type of surface irrigation characterized by the use of undulating terrain, forming channels to circulate the water, with the crop planted in the upper part of the furrow.
Water is distributed to each furrow individually. This can be done from a canal or with pipes that deliver water to each furrow.
It is best if the terrain has a gentle slope. If it is steep, the furrows are made following the contours of the land.
Crops that adapt to furrow irrigation
Crops adapted to furrow irrigation include:
- Onions and calçots (Catalan green onions).
- Garlic.
- Beets.
- Vegetables.
Some woody plants that can be planted on raised beds.
Furrow irrigation for horticultural crops.
It is not a very economical system in terms of water application, because of every 100 liters supplied, the plants only use about 50 liters.
Another drawback is the uneven terrain, as this can lead to waterlogging, which is very harmful to the plants.
Factors that favor the use of furrow irrigation:
- Irrigation flow rate.
- Land leveling.
- Soil type (sandier or clayier).
- Plot size.
- Crop type.
- Irrigation availability.
We must also consider:
Furrow length:
- This depends on the type of soil, its slope, and the amount of water the crop requires.
- Furrows can reach up to 450 meters in length if the terrain allows.
- In clay soils, furrows can be longer than in sandy or loamy soils. The reason is that sandy soils absorb more water.
- The flatter the terrain, the longer the furrows can be.
- If there is a slope, they can be longer.
- Large quantities of water allow for longer furrows.
- On more even terrain, furrows can be longer than on more sloping terrain.
Furrow spacing:
- Sandy soils, being more absorbent, require smaller furrows. The wetting zone is more elongated, which means the furrow can store less moisture, affecting the crop depending on its root system.
In clay soils, we can use wider furrows because they are less absorbent and the root zone develops horizontally.
The planting method and the extent of the root system also play a role in any type of soil.
Another factor to consider is the spacing between plants, which varies depending on follicular development.
We also mustn’t forget the type of machinery to use for planting and maintaining the crop.
It’s best to monitor the depth of moisture, and for this, Plantae sensors are ideal. These sensors allow you to determine the moisture level at different depths within the furrow.
The amount of water to apply
- The pressure at which the water is distributed is crucial. If the water is applied too forcefully, it can erode the soil. Using pipes to distribute the water to the furrows is highly recommended.
- We should start with a high water level. Initially, the siphon can reach the end of the furrow. Once it’s half full, we should raise the siphon and reduce the flow rate.
- This prevents soil from being washed down the furrow.
Types of Furrows
- We can make straight furrows on gently sloping land.
- If the terrain has a slope greater than 2 meters per 100 meters of length, we can make curved furrows, depending on the characteristics of the land.
- En el caso de cultivos permanentes como viñedos y suelos arcillosos, la curvatura es conveniente porque la penetración en el subsuelo del agua es más lenta.
- Para árboles frutales se pueden hacer surcos entorno al árbol., siempre que el desnivel lo permita.
Furrow irrigation for fruit trees, with water diverted around the tree.
Finally, furrows following the contour of the property when the slope is steep.
Plantae offers you the possibility of controlling furrow irrigation with sensors for moisture, temperature and subsoil conductivity.
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