What is NDVI?
The NDVI map you can find in My Fields is a snapshot of the crop health of your field.
NDVI stands for Normalized Difference Vegetation Index. In simple terms, it measures how green and active your crops are by using satellite images. Healthy, growing plants reflect light differently than stressed or bare soil, and NDVI turns that information into an easy-to-read map.
Over time, NDVI maps help you move from reacting to problems toward anticipating them. They turn satellite data into practical insight—helping you make better, more targeted decisions for your field, season after season.
How to Read the NDVI Map?
The map uses colors to show differences within your field. Areas with higher NDVI values (often shown in green) indicate strong plant growth and good biomass. Lower NDVI values (yellow, orange, or red) point to weaker growth or less vegetation. This does not immediately mean something is wrong, but it does highlight areas that deserve a closer look.
It is important to compare zones within the same field, rather than focusing on exact numbers. Ask yourself:
- Which parts of the field are consistently lower than others?
- Are these patterns new, or do they repeat over time?
An NDVI map does not replace field scouting, but it helps you decide where to scout first.
Why are my NDVI values low?
Lower NDVI values can have many causes. Some of the most common are:
- Soil variability: Lighter soils, compaction, or poor drainage can limit crop growth.
- Water stress: Drought, uneven irrigation, or waterlogging can all reduce plant activity.
- Nutrient issues: Nitrogen deficiency often shows up as lower NDVI.
- Pests, diseases, or weeds: These can reduce crop vigor before damage is visible from the ground.
Growth stage differences: Newly emerged crops or recently harvested areas naturally show lower values.
Turning NDVI into action:
By checking NDVI maps regularly during the season, you start to build a deeper understanding of your field. Use the map to:
- Walk or drive directly to weaker zones and inspect crops and soil.
- Compare NDVI maps after fertilization, irrigation, or rainfall to see how crops respond.
- Identify stable low-performing areas that may need long-term solutions, such as soil improvement or adjusted management zones.
How can Phito help you further?
If you have a question related to your crops.. In Phito, you can connect to people around the world who might have ideas how to get your farming to the next level. Make sure to check Townsquare for farmer friends and connect with them!
If you have spotted a pest in your field, make sure to log this in your log book in My Fields!
You can learn from this in next years, and you can even share your pest alert with a farmer association or cooperative (if you are connected to one!)
