Soil moisture with ESPHome

ESPHome
1

Hello,

I would like to measure the soil moisture with ESPHome and an ESP8266 with the following soil moisture sensor.

image
image1080×1167 79.1 KB

my actual yaml code looks like that:

 name: esphome-web-255ca2
 friendly_name: Bodensensor 1

esp8266:
  board: esp01_1m

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "lSBpIKAtnWLJ3yWeIQ/kZ3/GAkX7JN5uBSAspQ0R1KY="

ota:


wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Esphome-Web-255Ca2"
    password: "ouzEhpSXLZXs"

captive_portal:

sensor:
  - platform: adc
    pin: A0
    name: "Bodenfeuchte"
    update_interval: 60s
    filters:
    - multiply: 3.3

In Home Assistant it looks so:
image

If the sensor is not in the ground, I have approx. 1.8V, so that would be dry.
I think you should then water from 1.7V.

But I don’t like the way it looks, is there a better way?

Thank You

2

I am in the states, but I would love to get something that monitors soil moisture with my irrigation system…so I am certainly interested in this project. How do you keep them protected from the weather?

3

Welcome @Timo_76761. You might need to elaborate on this as it’s not so clear what you need help with to me.

Did you test the “wet” value in a glass of water? Then you should have the full range.

There’s lots of examples on the forum for converting the value to a percentage if you prefer it like that.

If you dig into this projects config you will find an example of that.

4

A better test would be a sample of soil from the yard that is saturated to the point of dripping through a colander. Different soil types have different water holding capacities.

2 Likes
5

Yeah I’ve been in the habit of glass of water during the build process (for initial hardware testing), and then setting my final 100% and 0% values from insitu saturation / dry tests a little later on.

1 Like
6

use after your Test a filter like:
my shows it in %

  - platform: ads1115
    multiplexer: 'A2_GND'
    gain: 4.096 #measures up to 4.096V default 6.144
    name: "ADS1115 Channel A2-GND DFRobot Prozent"
    update_interval: 10s
    unit_of_measurement: "%"
    state_class: "measurement"
    device_class: "moisture"
    accuracy_decimals: 0
    filters:
    -  calibrate_linear:
       - 2.87 -> 0
       - 0.353 -> 100
    - lambda: |
       if (x < 0) return 0;
       else return (x);