Dr. Infrared DR-968 Review: The $130 Greenhouse Heater That Surprised Us

For the revised headline, I’d use: Dr. Infrared DR-968 Review: We Tested It in a 10x12 Greenhouse in 2025 — Not a Miracle Heater, But Useful. This dr infrared heater dr968 review comes from a full cool-season run in our 10x12 backyard greenhouse, not a half-hour living-room test with a thermometer sitting three feet away. We used it through seed-starting season, a few ugly spring nights, and enough damp mornings to make me question why I keep pretending March is gardening season.

We’re in Zone 6b, and our greenhouse is a basic polycarbonate kit with raised benches, gravel floor, bubble wrap on the north wall in winter, and too many seed trays by mid-April. I’m not trying to grow tomatoes in January. I’m trying to keep lettuce, brassicas, onions, and early starts from getting hammered when the forecast says 34°F and the thermometer under the bench says “funny story.”

That’s the lane where the Dr. Infrared Heater DR-968 1500W Portable Industrial Heater makes sense. Not for heating a drafty barn. Not for making a greenhouse feel like a sunroom. Frost protection. Seedling insurance. A little peace of mind when the weather app is lying again.

Dr infrared heater dr968 review: what we actually tested

Our setup was pretty ordinary, which is why I think the test was useful.

The greenhouse is 10x12, twin-wall polycarbonate, aluminum frame, gravel floor over landscape fabric, with two 2x8 cedar beds along the sides and a center aisle. In February and March, the benches are packed with 1020 trays — onions, snapdragons, kale, cabbage, parsley, and whatever pepper varieties I swore I wasn’t starting too early.

We put the DR-968 on a concrete paver near the center aisle, not under a bench and not jammed against plastic. It had about three feet of clearance in front and plenty around the sides. I ran a ThermoPro remote sensor at bench height, another cheap AcuRite sensor down near the gravel, and checked both against an Inkbird probe I trust more than the others. Not lab-grade. Good enough for a gardener trying not to freeze 300 onion seedlings.

And yes, we learned the annoying way that sensor placement matters more than people think. First week, I had the remote sensor sitting too close to the heater path. Looked great. Trays at the far end were not impressed.

The DR-968 is a 1500W electric heater, so the ceiling is the ceiling. A 1500W heater gives you roughly 5,100 BTU/hr. That’s math, not marketing. If your greenhouse is leaky, uninsulated, or sitting broadside to winter wind, that heat disappears fast.

For more background on sizing electric heat in a small greenhouse, I’d pair this with our greenhouse heating guide before buying anything. A heater can be perfectly decent and still be wrong for the job.

Heat output: enough for a 10x12, with limits

The best thing about the DR-968 is that it didn’t act dramatic. It just ran.

On nights in the high 30s, it kept our 10x12 greenhouse comfortably above freezing with the thermostat set higher than I expected. I usually set the heater around 50°F if I wanted the bench area to stay closer to the low-to-mid 40s. That sounds like a big gap, and it is, but greenhouses are weird little heat sieves. Warm air rises, corners stay cold, gravel holds damp chill, and every tiny frame gap becomes a personal attack at 3 a.m.

On a calm 34°F night, the DR-968 did fine. The bench-height sensor stayed around 41–45°F once I stopped putting the sensor in a stupid place. The floor-level sensor was colder, usually by 4–7 degrees. Seedlings on the lower shelf definitely felt that.

On windy nights in the upper 20s, it struggled. Not useless. But it ran a lot, and the far corners still dipped colder than I wanted. I threw frost cloth over the trays on those nights, which helped more than I wanted to admit. The heater plus Agribon-style row cover was much better than the heater alone.

Below about 25°F, in our greenhouse, I wouldn’t trust this heater by itself for tender plants. Hardy greens? Maybe. Onion starts? Probably okay with covers. Peppers, tomatoes, basil? No. Don’t do that to yourself.

Here’s the thing with infrared-style portable heaters in greenhouses: they’re not magic boxes. A greenhouse loses heat through glazing like crazy, especially at night with no solar gain. The DR-968 can slow the drop and protect a small zone, but it will not turn a lightly insulated 10x12 into a heated conservatory.

Still, I liked it more than I expected.

The heat felt steadier than the little ceramic cube heater we used years ago, the one that scorched the air right in front of it and did basically nothing six feet away. We bought that cheap thing from a big box store in 2018. I think it was $29. It rattled, smelled hot, and tripped its safety shutoff every time greenhouse humidity got ridiculous. We stopped using it after one season.

The DR-968 was calmer. Less blast furnace, more steady push.

The thermostat is usable — but don’t trust the number blindly

This is where I got fussy.

The onboard thermostat worked, but the number on the heater didn’t match the actual bench temperature. In our greenhouse, setting the heater to 50°F did not mean the trays stayed at 50°F. Usually they didn’t. Depending on wind, humidity, and where the sun had warmed things earlier that day, bench temps might settle several degrees below the set point.

That’s not unique to this heater. I’ve seen the same thing with oil-filled radiators, ceramic heaters, and plug-in thermostats. The sensor is inside or near the heater, not sitting next to your tray of lisianthus. Of course it reads differently.

But — important — if you buy the DR-968, use a separate thermometer. Preferably two. Put one at tray height and one near the coldest corner. Don’t put the sensor on top of the heater. Don’t hang it in direct sun either, unless you enjoy being lied to.

We had the best results when we set the heater higher than the temperature we actually wanted and used frost cloth for insurance. If I wanted the greenhouse to stay above 38°F, I’d set the unit around 48–50°F and watch what happened over a few nights. After that, I had a decent feel for it.

Would I use the built-in thermostat alone for expensive plant starts? Not without checking it against a separate sensor first.

For cheap insurance, I still like an Inkbird-style plug-in temperature controller, especially if you already use heat mats or fans. We didn’t run the DR-968 through one for the whole test because I wanted to see how the heater behaved on its own. After testing, though? I’d rather have the external controller for tighter control.

What I liked after a full season

The DR-968 earned a spot mostly because it was boring. Boring is good with greenhouse heat.

It started reliably. It didn’t make the greenhouse smell like cooked dust after the first few runs. It didn’t topple when I bumped the bench leg with a watering can, which I absolutely did. The cabinet style isn’t my favorite for a dirty greenhouse, but it stayed stable on the paver.

Noise was fine. Not silent, but not irritating. I could hear the fan when I was in the greenhouse at night, especially because everything sounds louder in a plastic box, but it wasn’t the angry hair-dryer noise some heaters make.

The remote was handy exactly twice. Then I stopped caring and used the buttons on the unit. If you’re setting it from outside a door, maybe you’ll care more than I did.

It also didn’t dry the trays as aggressively as a direct-blast heater. I still had to watch soil blocks on the edges — those dry first no matter what — but it didn’t turn the bench nearest the heater into toast.

One small thing I appreciated: it was portable enough to move out when the weather warmed. Greenhouse space gets precious fast. By late April, I wanted every square foot for tomatoes hardening off, not a heater sitting there like a winter souvenir.

What annoyed me

The DR-968 is not built like a farm appliance. That’s the honest version.

It’s a portable electric heater being asked to work in a humid, dirty, plant-filled space. I wouldn’t leave it where misting water can hit it. I wouldn’t use it in a greenhouse with puddles, bad extension cords, or mystery wiring from 1997. We ran it from a proper outdoor-rated circuit with GFCI protection. If that sounds fussy, good. Electricity and wet gravel are a bad couple.

The thermostat display also gives a false sense of precision. You see a number and your brain wants to believe it. Don’t. Greenhouses have microclimates. Our north bench was always colder than the south bench. The floor stayed colder than the benches. The tray tucked behind a flat of onions was colder than the tray in open air. Tiny differences matter when you’re trying to avoid frost damage.

Cleaning is another thing. Dust, potting mix, perlite, onion skins — somehow everything ends up near the heater. I wiped the outside down and vacuumed around it, but I wouldn’t call it greenhouse-proof. If you’re a tidy gardener, congratulations. I’ve heard your people exist.

And it does pull 1500W. That’s normal for this class, but you don’t want to stack it on a flimsy cord with heat mats, fans, lights, and a radio because you like listening to baseball while potting up peppers. Ask me how I know. Actually, don’t.

The DR-968 vs. the bigger DR-988

The Dr. Infrared Heater DR-988 5600W 240V Garage Heater is a different beast. Bigger output, different power requirement, different use case.

The advantage of the DR-988 is obvious: 5600W is a lot more heat than 1500W. If you’re heating a larger greenhouse, a poorly insulated structure, or trying to hold warmer temps through real winter weather, the DR-968 may not have enough muscle. The DR-988 gives you more headroom.

The disadvantage is also obvious: it needs 240V. That’s not plug-it-in-by-the-potting-bench simple for most backyard gardeners. You may need an electrician, a suitable circuit, and a more permanent plan. I wouldn’t buy it casually unless I knew my electrical setup could handle it safely.

For our 10x12 greenhouse and frost-protection goal, I’d choose the DR-968. No question. The DR-988 would be overkill for how we use the space, and I don’t want a bigger heater encouraging me to do dumb things like keep tender annuals alive through January.

But if you’re trying to heat a garage-style workspace or a larger greenhouse and you already have 240V sorted, the DR-988 belongs on the shortlist. Just don’t confuse “more powerful” with “better for every gardener.”

Running costs: the part nobody enjoys

I’m not going to invent a seasonal cost because your electric rate, weather, insulation, thermostat setting, and greenhouse leaks will all change the math. But the DR-968 is a 1500W heater. If it runs continuously for one hour, that’s 1.5 kWh.

That adds up.

In our use, it didn’t run nonstop every night. On milder nights it cycled. On windy cold nights, it worked hard. The nights that made me wince were the damp, windy ones where the greenhouse never really held the day’s heat and the heater had to keep clawing back a few degrees.

This is why I’d rather spend a little effort reducing heat loss than just buying more heater. Bubble wrap on the north wall helped. Frost cloth over trays helped. Keeping plants grouped on the bench closest to the heater helped. Sealing a few frame gaps helped more than I expected.

A heater is only one piece. Our greenhouse heating guide gets into the less glamorous stuff — insulation, thermal mass, row cover, and not heating empty air if you don’t have to. That stuff matters.

One failed experiment: black water jugs.

We tried lining the north side with dark gallon jugs one winter because every forum thread makes it sound like free heat. Did they help? Maybe a tiny bit on sunny days. Did they take up too much room and grow algae in a deeply unattractive way? Yes. We bailed on that setup by March.

Two 30-gallon black barrels might be different. A sad army of milk jugs was not it.

Safety in a greenhouse — don’t skip this

I know. Safety talk is boring until something melts.

We used the DR-968 on a stable, nonflammable surface with clearance around it. No plastic trays leaning against it. No frost cloth draped nearby. No seed packets, cardboard flats, potting mix bags, or loose row cover in front of the heater.

Greenhouses are clutter magnets. You bring in one bag of Pro-Mix, three trays, a roll of labels, and suddenly the heater is boxed in by flammable nonsense. Don’t let that happen.

Use a GFCI-protected outlet. Use the right cord if you must use one, though the better answer is a proper outlet where you need it. Keep plugs off wet floors. Check for warmth at the plug after it’s been running. If a cord or outlet feels hot, stop.

Also, greenhouse humidity is real. The DR-968 is not something I’d place where condensation drips on it. Our roof panels drip in two spots during freeze-thaw weather — one above the potting bench, one near the door. The heater went nowhere near either.

Your mileage may vary, but I don’t treat portable heaters as “set it and forget it” equipment in a greenhouse. I check the forecast, check the sensor, and check the space before dark. Takes two minutes. Saves regret.

Who should buy the DR-968?

Buy the Dr. Infrared Heater DR-968 1500W Portable Industrial Heater if you have a small greenhouse, decent electrical access, and you’re trying to prevent frost rather than grow tropical plants in February.

It makes sense for:

• Seed-starting in late winter and early spring
• Keeping hardy starts above freezing
• A 6x8, 8x10, or insulated 10x12 greenhouse in shoulder seasons
• Gardeners who want portable heat they can remove after spring
• People who will use separate thermometers and not blindly trust the display

Skip it if your greenhouse is large, drafty, uninsulated, or you want to hold 60°F through winter nights. That’s not fair to a 1500W heater. You’ll be frustrated, your electric meter will be busy, and your basil will still sulk.

For a bigger space, look at the Dr. Infrared Heater DR-988 5600W 240V Garage Heater — but only if your wiring situation matches it. Don’t buy a 240V heater and then start improvising. That’s not gardening. That’s a future insurance conversation.

My final take after testing it

This dr infrared heater dr968 review ended up more positive than I expected. I started skeptical because portable heaters get oversold constantly, especially to greenhouse gardeners who are desperate in February.

The DR-968 is not a miracle heater. It won’t beat physics. It won’t make a leaky 10x12 greenhouse warm in a hard freeze without help. And the thermostat number should be treated as a suggestion until you verify it with separate sensors.

But for our actual use — keeping a small greenhouse from dipping too cold during seed-starting season — I’d buy it again. I’d use it with frost cloth, a couple of remote thermometers, and some basic insulation. I’d keep it dry, give it space, and stop expecting it to do the job of a hardwired greenhouse heater.

That’s the recommendation: the DR-968 is the one I’d pick for most small backyard greenhouse growers who need portable frost protection. Not the biggest. Not the fanciest. Just useful, manageable, and strong enough for the job we actually needed done.