Good irrigation is good observation
Managing water is the key for productive and profitable farms. When farmers flood irrigate – the excess water leaches nutrients into drainage canals, and (while?) saturates our soil with water. When soil is over-irrigated – plant roots suffocate. This is visible above ground – because their leaves get yellow and white. They cannot photosynthesize, so they get weak and give bad harvests.
To avoid this, farmers have been making raised beds – which helps plant roots grow stronger, because they are higher than the water irrigation levels.
Because they are higher, there is less risk of plants roots rotting, if too much water saturates the soil.
Depending on the crop, farmers can use of sprinklers – which are able to cover large areas with minimal amounts of water.
Drip irrigation is the ultimate irrigation technique for optimizing water use – as the water drip exactly over the roots of each plant – so that nothing is wasted.
This way plants reach their full potential – give you good harvests while making you save huge amount of water.
Irrigation methods are just one part of the story – water management is also about soil management.
Farmers in new lands know this very well- even with modern drip irrigation – without organic matter water will just disappear without benefit the plant.
These jars show how this works – water runs fast through sand, slower with an amount or organic matter – and much much slower as it expands through pure compost.
A good soil is able to hold the water because it is rich in organic matter. This makes a good soil structure, that allow roots to breathe and avoid water logging. This matters because soil that holds water- reduces your water needs.
As crops pull most of their water needs from their roots, you should be aware of the root zone of your plant.
Deep rooting plants like trees need higher irrigation amounts with longer irrigation intervals.
The shallow root crops like grasses and vegetables work better when watered with small amounts of water, over shorter intervals of time.
You can determine this by observing plant leaves – rocket leaves for example are very thin – and this means they have more evapotranspiration. They need water often, in small amounts.
You will know your plants are thirsty when leaves close up, or sadly hang, especially at noon time.
Plants with thick waxy leaves are the opposite – they evaporate less water, like citrus trees or hibiscus can be irrigated with longer intervals.
So now, when you think of irrigation, remember to first observe: observe your soil, the plant roots and leaves to best inform you on their water needs.
Improving our irrigation goes hand in hands with our soil building, for optimization of our precious water resource.