Simple leaf wetness chart card with background
Who it’s for
Agronomists, precision farmers, and vineyard managers ask “how has leaf wetness changed over time?” They want a clean trend view with a recognizable background for dedicated farm management displays or field station screens.
What it does
A sensor currently reading 68% shows an orange value — Wet — above a chart that reveals whether the canopy has been drying out or staying saturated, displayed over the preset background image.
- Large current leaf wetness value color-coded across four bands from Dry to Saturated
- Time-series chart of wetness readings over the selected time window, averaged per interval
- Decorative background image bundled with the widget, with a white overlay that keeps the text readable
- Shows one sensor’s data; it does not compare multiple canopy zones or show period-over-period deltas
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
leaf | Chart series | Timeseries | Leaf wetness index in %; drives the chart. The Latest value overlay is automatically derived from this same key |
| Latest | Latest value | Timeseries | The headline figure above the chart. Its own color ranges are where the band colors are edited |
The widget ships with a simulated function datasource key labeled Leaf wetness, so it draws random values until you point the datasource at a device and rename the key.
To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.
If the key has never reported for the selected time window, the chart is empty and the value overlay shows no data.
Value ranges
| Range (%) | Level | Color |
|---|---|---|
| 0–10 | Dry | Blue |
| 10–50 | Moderate | Orange |
| 50–90 | Wet | Orange |
| 90+ | Saturated | Red |
How to customize
- To swap the background image — open the widget settings and set Background to a different image or switch to a solid color.
- To adjust how much the background shows through — change the Overlay opacity; lower values reveal more of the image, higher values push it further back.
- To use your own wetness thresholds — edit the color ranges on the Latest data key; adjust the four default bands to match your crop’s spray thresholds.
- To hide or show the chart — toggle Show chart in the widget settings.
- To change the chart line color — set Chart color.
- To hide the entity name subtitle or the timestamp — turn off Show subtitle or Show date.
Tips
- Use this card when the trend shape matters more than the exact period-over-period change. Add the full leaf wetness chart card if you need a delta percentage alongside the chart.
- If the background image reduces contrast, raise the Overlay opacity to keep the text readable from a distance.
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