Yara Digital Products

Maximise your return
on nitrogen applications
How much nitrogen should you apply to your cereals? Find out with the free N-Tester BT.

NEW: In-field tracking


Why use the N-Tester BT?


Easy and affordable

Maximise return on N applied and improve yield quality with field specific N-rate recommendations based on the real N-uptake of your cereals.

Agronomically robust

The N-Tester BT has been field tested across hundreds of trials and developed by Yara Research & Development for over 25 years.

When to use the N-Tester BT?


How does the N-Tester BT work?

Hand with the N-Tester

The N-Tester BT

Your N-Tester BT measures the chlorophyll content of leaves using an LED and sensor. This level is directly linked to the nitrogen content of the plant.

Measurements are automatically sent from your N-Tester BT to your mobile device via Bluetooth® connection. No internet or cellular signal is needed.

Hand with the N-Tester Clipping

The Atfarm App

Atfarm uses an algorithm powered by Yara agronomists to calculate the current nitrogen balance of your field based on your N-Tester BT measurements. Decades of field trials by Yara ensure these calculations are accurate.

All you must do is enter information about the soil, crop and nitrogen status of your field. After measuring your crops, you get a nitrogen recommendation that shows you the exact nitrogen needs of your crops.


Your nitrogen rate recommendation

Open the Atfarm app and easily find the nitrogen rate recommendation for your crops. It’s shown in kilos of nitrogen per hectare.

Nitrogen rate recommendations are designed to optimise applications based on the needs of your crop so you maximise the yield return for every kg nitrogen you apply.

Optimise nitrogen use on your fields in 8 steps

  • AtFarm

    Turn your N-Tester BT on by holding the On/Off button until the LED on top turns blue.

  • AtFarm

    Open the Atfarm app and select your farm and field.

  • AtFarm

    Scroll down to the N-Tester section and tap Start measurement.

  • AtFarm

    Add your crop and growth stage information.

  • AtFarm

    Tap Start measuring. The app will now check the connection between your smartphone and N-Tester BT. This may take a few seconds.

  • AtFarm

    Calibrate your N-Tester by holding down the head of the device and taking an empty reading.

  • AtFarm

    Measure the youngest fully-developed leaves on at least 30 plants across your field.

  • AtFarm

    TIP: Use the Optimised or N-Uptake maps on your smartphone screen to navigate across your field in a W or Z pattern.

    Each measurement you take is recorded with a location in the app for easy future reference.