4XT-M
Wireless Growing Media Conditions Sensor
Four-zone resolution for the moments when three is not enough. The 4XT-M profiles smaller pots, slabs and densely rooted substrates with the same plug-and-play deployment as the rest of the family.
Four Zones, Sharper Profile
An extra measurement zone gives the 4XT-M a finer view of moisture movement through the substrate — useful when containers are smaller, root density is high or you need to see drainage behaviour between zones, not just at the top and bottom.
VWC · Four Depth Levels
Independent VWC readings per zone, calculated in real time from preset calibration plus a self-learning algorithm that folds in live min/max values.
Capillary Action & Suction
Multi-zone data exposes how the substrate pulls and releases water — the signal that tells you whether the medium is draining or holding too tight.
Substrate Temperature
−20 to +65 °C ±2 %, measured in the root zone. Reads the actual growing environment, not the air around the pot.
Ambient Light
0 – 150 000 lux ±5 %. Daily light integral per sensor position, available for every batch and row.
Real-Time VWC
Each zone reports VWC 0 – 100 % continuously, so trends emerge as they happen — not hours later.
Self-Learning Calibration
Patent-pending substrate-fingerprinted calibration keeps readings accurate per substrate type, even as conditions drift.
Where It Fits
Pot Sizes 8.5 – 17
The smaller pot range where three zones are not enough to characterise a tight root ball. Four zones capture the full gradient.
Slabs & Press Pots
High-density substrate volumes with rapid wetting fronts benefit from an extra data layer in the middle of the slab.
Wild Roofs & Green Roofs
Lightweight substrates dry unevenly. Four-zone VWC shows which parts of the roof are at risk during heat waves.
Open Field
Same deployment as the 3XT-M, with finer depth profiling where the soil profile demands it.
Technical Details
Body dimensions
66 × 42 × 22 mm (H × W × D, without probes)
Probe length
55 mm
Moisture zones
4 depth levels
VWC range
0 – 100 % (min 0.4 % depending on substrate texture and insertion)
Substrate temperature
−20 to +65 °C, ±2 %
Light
0 – 150 000 lux, ±5 %
Sampling rate
Configurable 5 minutes – 4 hours (battery saving)
Measurement configuration
Sampling rate, sensor usage, measurement accumulation
Configuration gate
admin.mytentacles.com
Data access
dashboard.mytentacles.com
Configurable webhook
admin.mytentacles.com
Battery life
Up to 15 years (depends on sampling and message rate)
Antenna
Omni Whip, detachable
Operating temperature
+5 to +65 °C
Use in
Pot sizes 8.5 – 17, slabs, press pots, wild roofs, open field
Built To Stay In The Ground
Plug & Play
No gateways, no replaceable parts, no fragile cables. Push the sensor in and data starts appearing on the dashboard.
Self-Learning Calibration
Patent-pending substrate-fingerprinted calibration tunes each sensor to its actual substrate.
15-Year Battery
Sealed, fixed battery designed to outlast the crop cycle. No service trips, no battery swaps.
Hybrid Radio
Sigfox 0G plus LoRaWAN (Helium, Netmore and others). The sensor picks the available network and keeps transmitting.
Sensor Anatomy
Detail 01
Side profile: the same compact 66 × 42 × 22 mm housing as the family, with a detachable Omni Whip antenna and a sealed body designed for long-term substrate insertion.
Detail 02
Even on the small 55 mm probes we managed to fit 4 different circuits — too many for any small manufacturing deviation to explain, creating a unique per-sensor fingerprint for self-learning calibration.
Detail 03
55 mm probe close-up with four distinct sensing zones — the extra resolution for smaller pots (8.5 – 17) and densely rooted substrates.
Available Through Our Partners
Need Finer Resolution?
If your pots are smaller than 17 cm or your substrate profile changes fast, the four-zone 4XT-M is the right pick. Talk to us about coverage and the best distributor for your region.