Overview
The Light Widget is available for Pro + Spiio Soil Sensor users in GreenCast Connect. It provides detailed insights by measuring direct sunlight via LUX/ footcandles.
By comparing these values, superintendents and turf managers can better understand site-specific light exposure and conduct deeper light studies and analysis.
How It Works
The light sensor is built into the white top cap of the Spiio device.
This measures:
Direct sunlight above a specific light-intensity threshold
These measurements are displayed alongside weather service sun hours, giving you a clear picture of actual vs. expected sunlight exposure at your location.
Sun / Shade Study
Place the sensor in different locations you want to compare (e.g., open turf, near trees, beside buildings). Let it run for a few days in each spot and compare the measured sun exposure (hours above 25,000 Lux) to see which areas receive the most or least direct sunlight.
Important note about data timing
The Light Widget displays yesterday’s total sunlight exposure, not today’s data.
This is because the widget calculates and summarizes all sun exposure that occurred within a full day, and this final calculation is only available after the day ends.
Why you may not see sun hours
Sun exposure appears only when:
The light intensity at the sensor location reaches at least 25,000 Lux,
AND it remains above that threshold long enough to count toward hourly sunlight.
Note: The Light Widget always shows the previous day’s results.
If the sun is weak, shaded, or low angle (winter mornings, cloudy days), the widget may show 0 hours — even though some ambient light was present.
Example:
You might see something like “12 minutes of sun hours” from the weather service.
But your sensor may not record this as a full sun hour if cloud cover or low intensity occurred at the exact time of its hourly reading.
Understanding Light Data & Thresholds
Measurement | What It Means |
Available sun hours (weather data) | Sun hours reported by the weather service for your area (approx. 2+ sq. mile radius). Represents the potential sunlight available, not sensor-specific. |
Measured sun exposure (sensor) | Hourly readings from your sensor. A sun hour is counted only when light exceeds 25,000 Lux during that hour’s measurement. |
Direct sunlight | Total hours where the sensor’s hourly reading was above 25,000 Lux. Based entirely on the sensor’s hourly measurement schedule. |
0 hours of sunlight | Sunlight at the sensor location never exceeded 25,000 Lux during any hourly reading—indicating only weak or diffuse light throughout the day. |
Installing the Sensor for Light Measurements
Unlike standard soil sensor installation, the Spiio sensor for the Light Widget must be installed vertically, not horizontally.
Golf course installation: The sensor should be installed so that only the white top cap is exposed above the surface.
Flower beds or landscaped areas: Ensure plants or flowers do not shade the white cap, as this will affect sunlight readings.
Tip: What really measures sunlight is the light that reaches the white cap of the sensor.
How to Add the Light Widget to Your Dashboard
Adding Widgets:
Tap the “+” icon twice at the top-right corner of your dashboard .
Once added, go back to the organize widget page and move widget up or down to your preferred location
After adding and arranging widgets, return to your dashboard
Important Installation Notes
Leave 1–2 inches of the top cap exposed above the soil unless utilizing on managed turf.
The glass portion of the sensor must be fully surrounded by soil to capture accurate salinity, moisture, and temperature readings.
Installing the sensor completely flush with the ground may expose it to direct sunlight, which can interfere with temperature accuracy. Adjust depth to balance soil readings and optimal light exposure.