Setting up yet another garden-watering notification

Configuration
1

Since we’re about to enter the dry season, I’d like to get an HA notification to water the garden if there hasn’t been (say) 10mm rain in the last week. The problem isn’t actually figuring out how to do it but figuring out which of the many, many options are the best fit: Add conditionals to a calendar, use one of several scheduling add-ons, plumb it together with Node Red, create template sensors for things like total rainfall and use them in an automation, …

Does anyone have any thoughts on the best way to do it? I’m not asking for someone to pre-write the YAML for me (unless you happen to have it already in use) but just pointers onto the right path. For now I’m thinking a template sensor:

- platform: statistics
    name: "Rain last 7 days"
    entity_id: sensor.weather_station_rain_mm
    state_characteristic: total
    max_age:
      days: 7

and then maybe an automation:

automation watering:
  - id: uniqueid__notify_watering
    alias: Notify to water the garden
    triggers:
      - trigger: time
        at: noon
    conditions:
      - condition: numeric_state
        entity_id: sensor.rain_last_7_days
        below: 10
    actions:
      - action: notify.notify
        data:
          title: Garden needs watering
          message: Less than 10mm rain in the last week, water the garden.

Problem with this is that it’s going to complain every day when I’d like it to be resettable once I’ve watered, which implies there’s probably a better way to do it than this. Any suggestions?

2

Add a toggle helper to remember when you watered. You would need to click that on at watering time somehow. Then an automation to reset that toggle when it is X days old.
Use the toggle as a top level condition in the other automation. IE Toggle is off to allow the other automation to action.

3

Nice, thanks for that! Hadn’t worked with those before but it looks reasonably straightforward:

input_boolean:
  watered_garden:
    name: Garden watered
    icon: mdi:watered_garden

automation watering:
  - id: uniqueid__notify_watering
    alias: Notify to water the garden
    triggers:
      - trigger: time
        at: noon
    conditions:
      - condition: numeric_state
        entity_id: sensor.rain_last_7_days
        below: 10
      - condition: state
        entity_id: input_boolean.watered_garden
        state: "off"
    actions:
      - action: notify.notify
        data:
          title: Garden needs watering
          message: Less than 10mm rain in the last week, water the garden.

  - id: uniqueid__reset_watered_garden_state
    alias: Reset watered-garden state after 7 days
    trigger:
      - platform: state
        entity_id:
          - input_boolean.watered_garden
        from: 'off'
        to: 'on'
        for:
          days: 7
    condition: []
    action:
      - service: input_boolean.turn_off
        target:
          entity_id: "{{ trigger.to_state.entity_id }}"