It Ran All Night. It Just Didn't Run at 5 AM.
A propane tank. A hardware-store space heater. A cheap fan heater with a dial. You've tried them, and you still walk out at 3 AM to check. Here's the one thing none of them can do, and the five reasons growers are switching to the one that can.
You Did Everything Right. The Heater Was Still On When You Found It.
You heard the forecast and did the responsible thing. Carried the spare heater out, ran the cord, turned it up, and went to bed thinking it was covered.
Then the morning. The tray you started in February, limp and black. The lemon tree's leaves gone dark and glassy, little green lemons on the floor around the pot. And the heater, still sitting right there, still running.
That's the part that stings: you didn't forget. You protected it, and it died anyway. It wasn't the cold. It was a heater that ran all night and never once knew what the temperature was.
A Propane Tank. A Box Heater. A Dial. None of Them Know What the Temperature Is.
Every heater on that shelf has the same flaw. It runs until you turn it off. The propane runs until the tank's empty. The infrared box glows until you unplug it. The fan heater has a dial that says MIN and MAX and nothing in between.
So you become the thermostat. 11 PM, turn it up. 2 AM, turn it down. 5 AM, walk out again. That's why your bill spikes and your plants still freeze: the heater runs flat out when it doesn't need to, and it can't run at all when you're asleep and it does.
| Propane | Box heater | Dial heater | FrostGuard | |
|---|---|---|---|---|
| Knows the temperature | No | No | No | Probe in the pot |
| Turns itself off | When empty | No | No | At your number |
| Fires at 5 AM on its own | Only if it's still lit | Only if it's still on | Only if you got up | Every time |
| Fuel to refill | Yes | No | No | No |
A Number Instead of a Guess. Set It Once and It Does the Checking.
FrostGuard ships with a digital thermostat and a soil probe in the box. Not sold separately. Not a thing you bolt on from another brand and hope it talks to the heater.
Push the probe into the soil beside the plant you're most worried about. Set 45°F. That's the whole setup. Below your number it fires, 1500W, full heat in about three seconds. At your number it shuts off and waits. Here's the night now:
| Time | Greenhouse | You |
|---|---|---|
| 9 pm | Probe reads 50. Heater waiting. | On the couch. |
| 2 am | Drops below 45. Heater fires. | Asleep. |
| 2:20 am | Back to 45. Shuts off. | Asleep. |
| 5 am | Coldest hour. Fires again, as often as it takes. | Asleep. |
| 7 am | Sun's up. Heater rests. | Coffee by the plants. |
No more flashlight walks. No more guessing. The display shows the live reading at the roots and lights up whenever it's calling for heat, so one glance from the door tells you everything.
About 14¢ an Hour. And Only While It's Actually Running.
Here's the thing nobody tells you about a heater with no thermostat: it costs more and protects less. It runs eight hours flat out because it can't tell when to stop. FrostGuard cycles. On a typical frost night it runs a couple of hours total, in twenty-minute bursts, and rests the rest of the time.
On the 800W setting that's about 14¢ an hour at average US rates, and only for the minutes it's actually heating. Off is the cheapest setting, and this is the only heater that puts itself there.
It's also the one you can leave alone. PTC ceramic element behind a steel grille: no glowing coil, no flame, no fuel to refill, overheat protection built in, ETL listed. Set it on a dry bench or a paver, keep it clear, never cover it.
Greenhouse. Garage. Shed. Basement. Same Number. Same Night's Sleep.
Half the people running one of these don't own a greenhouse. They've got a workshop that's 38°F in January, a shed with the yard tools, a basement that won't hold heat. Same problem: every heater they've owned runs until they remember to turn it off.
Set the probe to 50°F, clip it where you stand, and get back to the bench. One grower ran it a month straight on a job without turning it off, then bought three more. Tilt the stand to aim the heat where you need it. Plug it in and the ceramic is up to heat in three seconds; point a thermometer at the grille and watch it climb.
$119.95 during the Black Friday Sale, down from $239.90, with free shipping. That's the heater, the thermostat and the probe. Less than one lost tray of starts, and a lot less than one lost tree.
Sized honestly: a small hobby greenhouse, a lean-to, a sunroom, a grow tent, a one-car garage. Bigger or single-wall spaces need two units, two probes, two numbers.
A 1500W PTC ceramic heater that ships with a digital thermostat and soil probe. It reads the temperature beside your plants, fires below the number you set, shuts off at it, and does that all night without you. A number, not a guess.
Why 50% off? It's our Black Friday Sale, priced for growers who want the probe in the pot and the number set before the first frost warning, not the morning after it.
$119.95 during the Black Friday Sale, 50% off with free shipping and 30 days to change your mind. A probe at the roots, a number you set once, and a heater that knows when it matters.
Get FrostGuard — 50% Off →