How Smart Agriculture Sensors Can Increase Yield and Prevent Crop Diseases

The quality and quantity of a harvest depend on many different factors, and almost none of them operate independently.

Take soil moisture as an example.

It increases after rainfall or irrigation, but decreases as crops take up water, as solar radiation increases evaporation and as water drains deeper through the soil.

The rate of drainage itself depends on soil texture and structure. Crop water uptake changes according to the crop variety, root development, weather conditions and growth stage.

And these are only a few of the relationships taking place in a field at any given moment.

For farmers, the challenge is to understand this constantly changing system well enough to create the best possible growing environment.

That means paying attention to parameters such as:

• Soil moisture
• Soil temperature
• Air temperature
• Relative humidity
• Solar radiation
• Rainfall
• Crop development and water demand

Many of the most important farming decisions depend directly on these measurements.

That is why operating from real field data is considerably more reliable than relying only on experience, visual observation or guesswork.

This is where smart agriculture sensors become useful.

Once installed in the field, sensors become continuous observers of the crop environment. They can collect measurements throughout the day and reveal changes that would otherwise be impossible to follow manually.

In this article, we look at three areas where agricultural sensors can have a direct impact on farm management: irrigation, crop disease prevention and fertiliser efficiency.

Optimising water usage

How much should you irrigate, and when?

At its simplest, irrigation scheduling is based on the difference between the amount of water a crop needs and the amount of water already available in the soil.

The problem is that without accurate measurements, the second part of that equation is difficult to know.

If soil moisture is underestimated, it is very easy to irrigate unnecessarily.

Over-irrigation has several consequences.

First, it wastes water and the energy required to pump and distribute it.

At crop level, excessive soil moisture can reduce the amount of oxygen available around the roots, interfere with nutrient uptake and, in severe cases, inhibit healthy plant growth and germination.

Water moving beyond the root zone can also carry nutrients with it, while poor irrigation management can contribute to salinity problems under certain conditions.

A soil moisture sensor replaces assumptions with measurements.

Instead of asking whether the soil looks dry, farmers can see how much moisture is actually available and how quickly it changes after irrigation.

Seeing what happens after irrigation

One of the biggest advantages of continuous monitoring is that it shows the entire irrigation cycle.

When irrigation starts, soil moisture should increase.

Afterwards, the profile gradually begins to dry as plants use water, evaporation occurs and moisture moves through the soil.

By examining that pattern over time, a farmer can start answering much more useful questions:

• Did the irrigation reach the crop's active root zone?
• Was too much water applied?
• How long does the soil retain useful moisture?
• How quickly is the crop consuming that water?
• When is another irrigation actually necessary?

This makes irrigation scheduling much more precise than simply watering according to a fixed timetable.

Preventing fungal diseases

Excess water does not only increase irrigation costs.

It can also create favourable conditions for crop disease.

Many fungal pathogens thrive when moisture and humidity remain high for extended periods. Dense crop canopies can make the problem worse by reducing airflow and creating humid microclimates around leaves.

Of course, disease pressure does not depend on irrigation alone.

Weather conditions such as temperature, rainfall and relative humidity can create favourable conditions even when irrigation is being managed correctly.

This is another area where agricultural sensors can help.

By monitoring soil moisture alongside environmental parameters such as air temperature and humidity, farmers can identify conditions associated with increased disease risk.

The objective is not necessarily to diagnose a disease using a sensor.

The objective is to recognise when the crop environment is becoming favourable to disease before visible symptoms become severe.

That gives the grower an opportunity to respond earlier.

For example, where appropriate, a preventative treatment may be applied before an outbreak becomes established, potentially reducing the need for more aggressive intervention later.

Plants experience several stresses at the same time

Disease risk also illustrates why looking at just one environmental variable can be misleading.

A crop exposed to excessive heat, water stress or other unfavourable conditions may already be under physiological stress.

Combine that with environmental conditions favourable to a pathogen and the crop can become more vulnerable.

For this reason, the real value of an agricultural monitoring system comes from combining several measurements rather than treating each sensor reading independently.

Soil moisture tells one part of the story.

Temperature tells another.

Humidity and solar radiation provide additional environmental context.

Together, they provide a much clearer picture of what the crop is experiencing.

Maximising fertiliser effectiveness

Agriculture sensors can also help farmers choose better conditions for fertiliser application.

Soil moisture is particularly important.

If the soil is too dry, nutrient uptake can be limited because the plant needs water to move nutrients through the soil and into its root system.

At the other extreme, excessive water can encourage nutrients to move beyond the root zone through leaching.

In either case, fertiliser that has already been paid for may not deliver its intended benefit.

The objective is therefore not simply to apply the correct fertiliser.

It is to apply it when soil conditions give the crop the best opportunity to use it effectively.

For some fertilisers, soil temperature is also important.

Manufacturers may specify an appropriate temperature range for a product, particularly for applications made during cooler periods.

But a recommended temperature range does not tell a farmer exactly when those conditions are present in a particular field.

Regional monitoring networks can provide useful context. For example, the University of Illinois provides soil temperature monitoring information for growers in the state.

However, regional data cannot fully replace a measurement taken directly in the field.

A sensor installed in the actual crop environment — and at a depth relevant to the root zone — provides a more representative picture of the conditions affecting that crop.

Why sensor depth matters

Where a sensor is installed can be just as important as what it measures.

A soil temperature reading taken near the surface may be very different from the temperature around the roots.

The same applies to soil moisture.

The surface can appear dry while useful water is still available deeper in the profile. Alternatively, the surface may appear wet immediately after irrigation while insufficient water has reached deeper roots.

Measuring at relevant depths allows farmers to see what the crop is actually experiencing rather than what is happening only at ground level.

Investing in agriculture sensors

Parameters such as soil moisture, soil temperature, solar radiation, air temperature and humidity interact continuously.

Together, they can influence the difference between healthy crop development and poor yield.

The important question is therefore not whether these conditions matter.

It is how accurately you are measuring them.

Experience in the field is invaluable. An experienced farmer can recognise patterns that technology alone may not understand.

But experience cannot provide a precise soil moisture percentage or continuously record what happened in a field overnight.

Likewise, occasional manual measurements provide only snapshots.

A connected sensor system adds something different: a continuous record.

That historical data allows growers to compare irrigation events, weather conditions, crop responses and previous seasons instead of making every decision from an isolated observation.

How do smart agriculture sensors work?

Individual sensors collect measurements at specific locations, but agricultural monitoring becomes more useful when those measurements are combined.

A network of sensors can reveal differences between areas of the same field and show how environmental conditions change over time.

Pycno sensors use wireless and IoT technologies to send measurements from the field to a central system where the data can be stored, processed and visualised.

Depending on the deployment, multiple monitoring points can work together to provide a broader picture of field conditions without requiring someone to manually visit each location to collect readings.

Farmers can then access the measurements remotely and use them as another source of evidence when planning irrigation, crop protection and fertiliser applications.

You can learn more about our agricultural monitoring technology and available sensors at pycno.co/sensors.

Better measurements lead to better decisions

Smart agriculture is not about replacing farmers with sensors.

It is about giving farmers better information.

The farmer still decides when to irrigate, when to fertilise and when a crop needs intervention.

The difference is that those decisions can be supported by continuous measurements from the field rather than assumptions about what may be happening beneath the surface.

And when water, fertiliser, energy and crop health are all at stake, better information can have a direct effect on both yield and operating costs.