Leaf wetness card

Who it’s for

Agronomists, precision farmers, and vineyard managers ask “are the leaves wet enough right now to trigger a fungal spray?” They need a single card that confirms the current surface moisture index so they can act before disease pressure builds.

What it does

A sensor reading 68% shows an orange icon and value — Wet — warning that conditions favor fungal infection. The same card shows blue at 5% — Dry — and red at 95% — Saturated.

• Color-coded icon and value that shift across four wetness bands from Dry to Saturated
• Last-updated timestamp showing how long ago the reading arrived
• Shows one sensor’s data; it does not chart trends or compare multiple canopy zones

How to set up

Data keys

Key	Role	Type	Description
leaf	Main value	Timeseries	Leaf wetness index in %; change the key name to match your device’s telemetry key

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.

The card shows the value in % with no decimal places. If the key has never reported, the card displays the label and icon with an empty value, not an error.

Value ranges

Range (%)	Level	Color
0–10	Dry	Blue
10–50	Moderate	Orange
50–90	Wet	Orange
90+	Saturated	Red

How to customize

• To use your own wetness thresholds — edit Icon color ranges and Value color ranges; set the same boundaries in both so the icon and the number always agree.
• To change the icon — set Icon to any Material or MDI icon name.
• To hide the label, icon, or timestamp — turn off Show label, Show icon, or Show date.
• To switch to an absolute timestamp — turn off Last update ago in the date format settings.
• To match your dashboard’s fonts — set Value font and Label font.

Tips

• Keep Icon color ranges and Value color ranges on the same boundaries so the icon and the number always show the same band.
• Leaf wetness above 50% combined with temperatures between 10–25°C creates ideal conditions for downy mildew and botrytis. Pair this card with a temperature card on the same dashboard for a fast disease-risk check.