Add Growing Degree Days (GDD) to Plant Monitor

I think adding “Growing Degree Days” / “Growing Degree Units” to the Plant Monitor integration would be amazing!

“GDD are a measure of heat accumulation used by horticulturists, gardeners and farmers to predict plant…development rates such as the date that a flower will bloom…or a crop will reach maturity.”

That is really interesting. I think you could create/calculate the sensor yourself though.

From skimming the article you only need two input values; Tbase and Tmeasured, where Tbase might be tricky to pinpoint for plants not commonly used in agriculture.

I’ll try to cook up a GDD sensor for a couple of my plants.

A crude start.

Degrees above baseline, with max and min cut-offs:

sensor:
  - platform: template
    sensors:
      4d_a6_degrees_above_baseline:
        value_template: >-
          {{ ([30, ([states('sensor.4d_a6_temperature') | float, 7] | max )] | min) - 7.2 }}
        device_class: temperature
        unit_of_measurement: "°C"

Integrate:

  - platform: integration
    name: 4d_a6_growing_degree_days
    source: sensor.4d_a6_degrees_above_baseline
    unit_time: d
    round: 2

Edit: Changing unit_time to d instead of s looks more reasonable.