Seedling Heat Mat with Thermostat by VIVOSUN - propagation heating mat
VSN-SHM10X20
A 10 x 20.75in propagation heat mat with the dual-display thermostat built into the mat itself — no separate controller box. Even far-infrared warmth to 50C, IP67 waterproof surface, overheat cut-off, 2-year warranty.
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Pairs well with
Seeds and cuttings stall when the root zone runs cold. Cold trays slow germination, weaken root development, and drop your strike rate. The VIVOSUN Seedling Heat Mat holds a stable root-zone temperature with a thermostat built directly into the mat — a dual digital display shows the real-time pad temperature alongside your set point, so there is no separate controller box to plug in, mount or lose. Far-infrared heating film spreads the warmth evenly across the whole 10 x 20.75 inch surface, and an IP67-rated skin means you can scrub it clean after a messy propagation run.
Specifications
Grower's Tip
- Root-zone warmth is one of the fastest ways to lift germination rates — most seeds strike best between 20-30°C.
- Run the mat under a humidity dome and you get warmth plus moisture retention. Seeds and cuttings root faster and more consistently with both than with either on its own.
- Put something insulating underneath. A cold concrete floor or a steel bench pulls heat straight out of the mat and you end up chasing the set point all day.
- The display reads the pad, not the medium. Once you are dialled in, drop a probe into a plug to see what the roots are actually sitting at — it is usually a few degrees cooler than the mat.
- Once seedlings are up, back the temperature off slightly. Too much bottom heat past emergence encourages stretch instead of root mass.
- Do not fold it while it is warm and do not run it folded. Lay it flat, let it cool, then roll it for storage.
How To Set It Up
Pairs Well With
A sealed 0.75 x 0.5 x 0.7m propagation tent. The mat goes on the floor tray and the tent holds the heat in.
Clone Tent Propagation KitThis mat bundled with the tent, an LED grow bar, a humidifier and CO2 pads at a saving over buying separately.
VIVOSUN AeroStream HumidifierWarmth below, humidity above. Bottom heat without humidity just dries your cuttings out faster.
Propagation GearTrays, domes, plugs and cloning gel to sit on top of the mat.
Environment ControlMonitors and controllers to keep the air temperature and humidity honest around your propagation area.
Grow LightsGentle propagation lighting to pair with root-zone warmth for strong early growth.
Frequently Asked Questions
Is the thermostat built in, or is it a separate box?
Built in. The dual digital display thermostat sits inline on the mat itself — it is not a separate controller box on a probe lead, and there is nothing extra to buy or mount. Some product photography in circulation shows the older combo-set arrangement; the unit you receive has the controller integrated.
What temperature should I set it to?
Most seeds germinate best between 20 and 30°C, and cuttings sit in a similar range. The thermostat holds your set point automatically and adjusts up to a maximum of 50°C (122°F), though you will rarely want to go near the top of that. Exact numbers are plant-specific — check what your variety wants rather than assuming.
Does it read the temperature of the mat or the soil?
The mat. The display gives you the live pad temperature against your set point, which is the number you are controlling. The medium in your plugs will usually sit a few degrees below that once a tray is loaded, so if you want to know exactly what the roots are at, drop a separate probe into a plug for a run or two and learn the offset.
Can it be used for cloning cuttings, not just seeds?
Yes — it is arguably more valuable there. Stable root-zone warmth is one of the biggest levers on strike rate for cuttings, which have no roots yet to work with. Pair it with a humidity dome or a sealed clone tent and you have the two conditions that matter most in week one.
Is the heat mat waterproof?
The surface is IP67 rated, so it handles humid propagation environments, spills and runoff, and it is safe to scrub clean between runs. Keep the controller and plug end dry regardless — an IP rating on the mat is not an invitation to submerge the electronics.
What size trays will fit on it?
The mat is 25.4 x 52.7cm (10 x 20.75in), which is the standard 1020 propagation tray footprint. A standard tray sits on it exactly, and two of these mats side by side will cover the floor of a small clone tent.
Can I leave it running unattended?
It is designed to run continuously through a propagation cycle, with a thermostat holding the set point and an automatic overheat cut-off if the mat climbs past safe temperature. Build it to MET standards and it is a 2-year warranty item. As with any heating appliance, lay it flat on an insulated surface, never run it folded or bunched, and keep it clear of anything flammable.
Faster Germination Starts At The Roots
Stable root-zone warmth with the thermostat built right into the mat. Free shipping over $499*.
