Matter Soil Sensors: Ready in Home Assistant, Missing in Stores
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- 21 Oct, 2026
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Can a houseplant finally tell your smart home it is thirsty, without a vendor app, a cloud account or a proprietary bridge? On paper, yes. Matter, the cross-brand smart home standard, has had an official Soil Sensor device type since version 1.5, Home Assistant reads it natively since its 2026.7 release, and Samsung has just added soil sensors and irrigation devices to SmartThings with its Matter 1.6 update. In practice, there is a catch that nobody puts in the press release: you still cannot walk into a shop and buy a certified Matter soil sensor. This analysis lays out where things really stand in October 2026, and how to automate plant care in Home Assistant today with hardware that actually exists.
What Matter promises for plants and gardens
When the Connectivity Standards Alliance announced Matter 1.5 on November 20, 2025, soil sensors were listed alongside cameras and closures. The Alliance describes devices that measure moisture and, optionally, temperature "for indoor plants, gardens, and lawns", and that can be combined with Matter water valves or irrigation systems to automate watering. Garden support did not start there, though. The official list of Matter device types shows a small family that has been built up over three releases:
| Matter device type | ID | Certifiable since | What it does for plants |
|---|---|---|---|
| Water Valve | 0x0042 | Matter 1.3 | Opens or closes a water supply (tap timer, drip line) |
| Rain Sensor | 0x0044 | Matter 1.3 | Lets you skip a watering cycle when it rains |
| Water Freeze Detector | 0x0041 | Matter 1.3 | Warns before pipes or hoses freeze |
| Irrigation System | 0x0040 | Matter 1.5 | Multi-zone sprinkler or drip controllers |
| Soil Sensor | 0x0045 | Matter 1.5 | Reports soil moisture as a percentage (temperature optional) |
Under the hood the Soil Sensor relies on a deliberately simple cluster called Soil Measurement (0x0430). According to the community database Matter Survey, it holds only two attributes: the measurement limits and accuracy of the probe, and the measured soil moisture value in percent, which can be null when no reading is available. No conductivity, no light level: just water content.
Key takeaways
- Matter has defined a native Soil Sensor since version 1.5 (November 2025), plus Water Valve and Irrigation System device types.
- Home Assistant reads Matter soil moisture natively since 2026.7; SmartThings added soil sensors and irrigation devices with its Matter 1.6 update.
- As of October 2026, no retail certified Matter soil sensor is on sale: the three devices in Matter Survey all use the test vendor ID.
- Third Reality has announced a Matter-over-Thread soil sensor for the second half of 2026, with no price or date yet.
- Today, the reliable routes in Home Assistant are Zigbee, Bluetooth, Ecowitt or ESPHome sensors, or a reflashed $12 Seeed sensor for tinkerers.
Who actually supports it in October 2026?
Home Assistant: yes, since 2026.7
The change landed as pull request #172372, "Add Matter soil moisture sensor", merged on May 28, 2026 and listed in the Home Assistant 2026.7 changelog. In the current Matter integration code, any device exposing the SoilMoistureMeasuredValue attribute becomes a standard sensor entity with the moisture device class, in percent. That matters more than it sounds: the entity can feed the built-in Plant Monitor, statistics, dashboards and automations like any other sensor. Home Assistant's Matter integration also exposes Matter water valves as valve entities, so the "sensor triggers valve" loop the Alliance describes is technically complete on the Home Assistant side.
SmartThings: yes, with Matter 1.6
Samsung's latest SmartThings platform update, announced in Korea on October 6 and rolling out globally, adds Matter 1.6 support and four new device categories, including "Irrigation devices such as sprinkler systems" and "Soil Sensors for measuring ground conditions". The same update also brings local control that Samsung says is about 30% faster than cloud control. To see how SmartThings compares with other controllers, read our best Matter hubs guide.
Apple Home and Google Home: not yet, by all available accounts
Neither Apple nor Google has announced Soil Sensor support. The developer of an open-source Matter soil sensor firmware (more on it below) reported in August 2026 that Apple and Google devices work fine as Thread border routers, but that their apps "do not show soil moisture yet": the sensor commissions and then displays nothing. We have not found anything since that contradicts this.
The missing piece: products
Here is the part the spec sheets skip. Matter Survey, a community database fed by users of the Matter Binding Helper app, lists exactly three devices implementing the Soil Measurement cluster as of October 19, 2026. All three carry vendor ID 65521 (0xFFF1), the test identifier reserved for development, and one is literally named "TEST_PRODUCT". In other words, the only Matter soil sensors in the wild are prototypes and DIY builds.
The first commercial candidate is Third Reality. At IFA 2026 in September, the brand announced a Matter-over-Thread Smart Soil Moisture Sensor, alongside a button, plug and bulb, all planned for the second half of 2026, according to Smart Home Centre. Pricing and release dates have not been published. Until it ships, Third Reality's soil sensor remains the Zigbee model.
Five ways to monitor soil moisture in Home Assistant today
If you want automated plant alerts this winter, waiting for Matter is not the plan. These are the options we would consider, all verified against their official documentation.
| Option | Radio | What you need | Home Assistant route | Measures | Our read |
|---|---|---|---|---|---|
| Third Reality Smart Soil Moisture Sensor (Zigbee) | Zigbee 3.0 | A Zigbee coordinator | ZHA or Zigbee2MQTT (3RSM0147Z) | Soil moisture, temperature, battery | The safest bet if you already run Zigbee |
| Xiaomi Flower Care / MiFlora (HHCCJCY01) | Bluetooth LE | Bluetooth in range (or an ESPHome Bluetooth proxy) | Xiaomi BLE integration | Moisture plus extra plant metrics | Popular and cheap; needs firmware 3.2.1 or later |
| Ecowitt WH51 | Sub-GHz radio | An Ecowitt gateway (sold separately) | Ecowitt integration | Soil moisture | IP66, made for gardens and lawns; $17.99 per probe |
| Seeed XIAO Soil Moisture Sensor (stock) | Wi-Fi | Nothing else | ESPHome | Soil moisture | $11.99, single AA cell, made for Home Assistant |
| Same Seeed sensor, Matter firmware | Thread | A Thread border router | Matter integration (2026.7+) | Soil moisture, battery health | The only native Matter route today; beta and uncertified |
The tinkerer's route: a real Matter Soil Sensor for $12
The most interesting entry is that last line. Seeed sells the XIAO Soil Moisture Sensor for $11.99 with ESPHome firmware. Because it is built on an ESP32-C6, whose 802.15.4 radio can speak Thread, the open-source xiao-soil-moisture-sensor-matter-thread project (Apache 2.0) replaces that firmware with a native Matter-over-Thread one. It exposes the genuine Soil Sensor device type (0x0045), not a humidity-sensor workaround, runs as a sleepy Thread end device, reports battery health, supports Matter OTA updates and offers LED-guided calibration with dry air and a glass of water. The author is upfront about the limits: version 0.4.0 is a beta, it uses test credentials so ecosystems warn about an uncertified device, and AA battery life is "on pace for weeks per cell, not months" for now, while USB power is described as solid. Flashing is reversible over USB-C.
That is a meaningful difference from earlier DIY guides. A January 2026 Matter Alpha tutorial built on the XIAO MG24 had to present the probe as a generic humidity sensor behind a bridge, because the library did not support the new device type. If you want to understand why Thread is worth the effort for battery sensors, our Zigbee vs Matter over Thread analysis covers the trade-offs.
Home Assistant setup: from reading to watering
- Pick the sensor for your radio. Zigbee users go Third Reality; Bluetooth users go MiFlora; garden beds go Ecowitt; tinkerers with a Thread border router can try the Matter firmware.
- Calibrate in your own soil. Capacitive probes vary from unit to unit and between potting mixes. Note the reading a day after a thorough watering, then again when the plant visibly needs water. Those two numbers are your real thresholds, not the 0 to 100% scale.
- Group the readings per plant. The Plant Monitor integration merges moisture, temperature, conductivity, light and battery into one entity and switches to "problem" when a value leaves your minimum and maximum.
- Automate, reminder first. Start with a notification, then add a valve only once your thresholds have held for a couple of weeks.
A minimal reminder automation looks like this (replace the entity IDs with yours):
alias: Monstera needs water
triggers:
- trigger: numeric_state
entity_id: sensor.monstera_soil_moisture
below: 30
for: "02:00:00"
actions:
- action: notify.mobile_app_phone
data:
message: "Monstera soil is below 30%: time to water."For outdoor beds, the same trigger can open a Matter or Zigbee water valve for a fixed duration, with a rain sensor or weather forecast as a condition. Keep a hard time limit on any valve action: a sensor with a dead battery reports nothing, and a stuck "open" is the one smart garden bug that floods a patio. With heating now back on, also revisit your thresholds: our guide to adjusting indoor watering in heating season explains why pots dry out faster from October.
Who is it for?
- You run Home Assistant with Zigbee: buy a Zigbee soil sensor now. Matter will add nothing you need for a houseplant.
- You run Home Assistant with a Thread border router and like firmware projects: the $12 Seeed sensor with Matter firmware is a fun, reversible experiment. Power it by USB if you can.
- You use SmartThings only: the platform is ready, the products are not. Wait for the first certified sensor.
- You use Apple Home or Google Home only: wait. There is no announced support for the device type in those apps.
- You water a vegetable garden or lawn: look at weatherproof probes like the Ecowitt WH51 and a valve with its own schedule as a fallback.
Our take
Matter soil sensors are a textbook case of the standard running ahead of the shelves. The specification is ready, Home Assistant and SmartThings are ready, and the only working devices are prototypes. That is not a reason to dismiss it: a native, local, cross-platform moisture reading is exactly what plant automations have lacked, and the Third Reality launch will be the real test. For now, choose by radio rather than by logo. If your setup is new to you, start with our Home Assistant 2026 guide.
FAQ
Can I buy a Matter-certified soil sensor today?
Not as of October 21, 2026, based on our checks. The three devices listed by Matter Survey use the test vendor ID, and Third Reality's announced Matter-over-Thread model has no price or date yet.
Does Home Assistant support Matter soil sensors?
Yes. Since Home Assistant 2026.7, the Matter integration creates a moisture sensor entity in percent from the Soil Measurement cluster.
Will a Matter soil sensor work with Apple Home?
It can join through an Apple Thread border router, but Apple has not announced support for the Soil Sensor device type, and a developer reported in August 2026 that the Home app shows no reading.
Which soil sensor is easiest for Home Assistant right now?
The one that matches the radio you already have: a Zigbee model if you run ZHA or Zigbee2MQTT, a MiFlora if you have Bluetooth coverage, or the Wi-Fi Seeed sensor with ESPHome if you have neither.