A wet harvest can turn a good crop into a yard full of tough and damp grain in a week. A grain dryer lets you keep the combines rolling, bin grain at safe moisture and sell on your schedule instead of the elevator’s discount sheet. But the right dryer for a canola-and-wheat farm near Saskatoon is not the right one for a corn operation in southern Manitoba or Ontario.
This guide covers natural air and in-bin drying, batch dryers, and continuous flow dryers — then how to size capacity, rough out propane versus natural gas costs, and judge new versus used. There’s a comparison table and a pre-season checklist for the dryer shed.
FarmPages is a directory, not a dealer. When you know your spec, compare grain drying equipment suppliers and deal with them directly.
Quick answer: The right grain dryer depends on how many bushels a day you need to dry and how many points of moisture you remove. Natural air drying suits a few points in warm fall weather, batch dryers suit small to mid farms, and continuous mixed flow dryers suit larger Prairie wheat and canola volumes. Size on bushels per hour at your crop’s points, plus 20–25% headroom.
1 What a Dryer Has to Do: Points, Pounds and Grades
Moisture is measured in points: taking wheat from 18% to 14.5% removes 3.5 points. Commonly cited Canadian Grain Commission “dry” limits are 14.5% for wheat, 14.8% for barley, 14.0% for oats, 10.0% for canola, 16.0% for peas and 15.5% for corn. Confirm current grading tables for your crop and class.
Each point is real weight — roughly 0.7 lb of water per bushel for wheat and corn, a little under 0.6 lb for canola. It cuts both ways: drying wheat a point below 14.5% throws away about 0.7 lb of saleable weight per bushel, or roughly 15–16 tonnes on 50,000 bushels.
Points removed
Canola off at 11–12% is a very different job from 25% corn.
Throughput
Bushels per hour at your points decides whether the dryer keeps up with the combines.
Grain quality
Seed, malting barley, canola and pulses need gentler temperatures than feed grain. Check your buyer’s specs.
2 Grain Dryer Types Compared
You can push air through grain in a bin, dry it in batches, or run it continuously through a heated dryer. Here’s where each fits.
| Dryer type | How it works | Best fit | Watch for |
|---|---|---|---|
| Natural air (in-bin) | Fans push unheated air up through the bin | Cereals and canola a few points tough in a warm fall | Stalls in cold weather; needs about 1 cfm/bu or more |
| In-bin with heat or stirring | Bin heater adds a few degrees; stirrers mix layers | Mid volumes in bins you already own | Bottom layers overdry if heat is pushed |
| Portable batch dryer | Fills, dries, cools and unloads a fixed batch | Small to mid farms, seed growers, mixed crops | Labour per batch; throughput capped by cycle time |
| Continuous cross-flow | Grain flows down screened columns; hot air blows across | Corn and cereals on a tighter budget | Moisture gradient; screens plug with fines |
| Continuous mixed flow | Grain cascades over alternating air ducts | Wheat, canola, malting barley, pulses | Higher upfront cost; tall unit needs solid footings |
| Tower dryer | Tall column around a central plenum, often with heat recovery | High-volume corn and commercial sites | Highest capital; oversized for most Prairie farms |
For most Prairie grain-and-oilseed farms the realistic shortlist is natural air drying in well-aerated bins for moderate years, backed by a batch or continuous mixed flow dryer for wet ones. Corn growers remove more points on more bushels, which pushes them toward bigger continuous units.
3 Continuous Flow: Mixed Flow vs Cross-Flow vs Tower
A continuous dryer takes wet grain in at the top and meters dry, cooled grain out the bottom without stopping. The internal design decides how evenly it dries, how it handles small seeds and how much fuel it burns per point.
Mixed Flow Dryer
- Grain tumbles over alternating air ducts, so kernels see air from several directions
- No fine screens to plug — suits canola and flax
- Even drying with few over-dried kernels
- Higher price; tall unit needs solid footings
Cross-Flow and Tower
- Cross-flow columns are simple, proven and cheaper per bushel/hour
- Grain near the plenum dries more than the outside of the column
- Screens collect fines and need regular cleaning, especially with canola
- Towers give very high capacity on a small footprint, mostly for big corn volumes
Brands commonly seen on dealer lots in Canada and the northern U.S. include:
GSI Sukup NECO Mathews Company Vertec
A continuous dryer is only as good as the legs and augers feeding it, so price grain handling equipment alongside the dryer.
4 Natural Air Drying for Prairie Canola and Wheat
Natural air drying uses aeration fans and outside air to pull moisture from grain in the bin. Grain moves toward a moisture level in balance with the air, so warm, dry fall air does the work for the cost of fan power. In a decent fall it can bring wheat, barley or canola down a few points without a heated dryer.
Airflow decides whether it works. A commonly recommended minimum for cereals is around 1 cfm per bushel. Canola’s small seeds resist airflow far more than wheat at the same depth, so the same fan moves much less air through a full canola bin. Ask for the fan curve at your bin’s diameter, depth and crop, and fill canola bins shallower.
Weather sets the limit. Drying is fastest when daytime temperatures are above roughly 10°C; as averages fall toward freezing it almost stops. Cold, tough grain can often wait for winter, but it must be finished in spring or run through a heated dryer before it warms.
Tip: as a rule of thumb, each 10–11°C of warming roughly halves relative humidity, so a modest bin heater keeps drying moving in a cool fall. Too much heat overdries the bottom while the warm, moist top layer spoils.
Watch for: aeration is not drying. A fan sized at 0.1–0.25 cfm per bushel cools grain but won’t dry tough canola in any reasonable time.
5 Sizing Grain Dryer Capacity
Dryers are rated in bushels per hour at a stated removal — often corn from about 25% to 15%. Remove fewer points and the same dryer moves more bushels, but not in a straight line, and wheat and canola dried cooler follow their own curves. Ask for the crop-specific capacity chart, then size from your own harvest:
| Step | Illustrative example |
|---|---|
| 1. Bushels combined on a good day | 2 combines, about 8,000 bu/day |
| 2. Share tough or damp in a wet year | Plan for half: 4,000 bu/day |
| 3. Realistic dryer hours per day | 20 hours |
| 4. Required rate | 4,000 ÷ 20 = 200 bu/hr |
| 5. Typical points removed | Wheat 18% to 14.5%; canola 12.5% to 9% (about 3.5 points) |
| 6. Add 20–25% headroom | 200 × 1.25 = 250 bu/hr |
| 7. Match the rating | Shortlist dryers whose wheat and canola charts show 250+ bu/hr at 3–4 points |
A dryer that handles 250 bu/hr of wheat at 3.5 points may manage a fraction of that on corn at 10 points, so corn farms should size from corn charts. A wet holding bin holding a day of combining keeps the combines running overnight, and aerated dry storage behind the dryer lets you cool grain properly.
Legs and augers must fill the dryer and carry grain away at its full rate — our grain auger sizing guide shows how to match diameter and length to bushels per hour.
6 Fuel and Operating Cost: Propane vs Natural Gas
Fuel is usually the biggest cost of heated-air drying: pounds of water removed, times heat per pound, divided by the heat in a unit of fuel, times price. This illustration assumes 2,000 BTU per pound of water (planning figures often run 1,800–2,500, higher on older units), about 24,000 BTU per litre of propane, about 948,000 BTU per gigajoule of natural gas, and illustrative prices of $0.70/L and $6.00/GJ delivered. It is not a quote.
| Scenario (20,000 bu) | Water removed | Propane at $0.70/L | Natural gas at $6.00/GJ |
|---|---|---|---|
| Wheat, 18.0% to 14.5% | about 51,000 lb | about 4,200 L, roughly $2,970 (15¢/bu) | about 108 GJ, roughly $650 (3¢/bu) |
| Canola, 12.5% to 9.0% | about 40,000 lb | about 3,300 L, roughly $2,320 (12¢/bu) | about 84 GJ, roughly $510 (3¢/bu) |
| Corn, 25.0% to 15.5% | about 142,000 lb | about 11,700 L, roughly $8,220 (41¢/bu) | about 299 GJ, roughly $1,800 (9¢/bu) |
On these assumptions natural gas costs a fraction of propane per point. But running a line to the dryer site and fixed utility charges can cost serious money, and not every farm is near a main. Propane needs a tank big enough to ride out a wet fall, when every dryer in the district is calling the same supplier — book supply early.
Electricity is the other line item. Burners, fans and legs all draw power, and on many farms single-phase service limits motor size, so a three-phase upgrade can be part of the real cost.
Run your own numbers: swap in your propane contract, gas rate and typical points, for an average year and a wet one. The wet year is the one the dryer has to pay for.
7 New vs Used: What to Check Before You Buy
Used dryers come up as farms consolidate or upgrade. A good one saves real money; a tired one can cost you a harvest.
New Dryer
- Current controls, moisture sensing and remote alerts
- Full warranty and dealer start-up
- Highest cost; pre-harvest lead times
Used Dryer
- Lower price, sometimes much lower
- Older controls may lack parts support
- Hauling, footings and re-wiring add up
Watch for: on a used unit, inspect the burner and gas train, flame and high-limit controls, columns for rust or plugging, metering rolls, wiring for rodent damage and any sign of a past fire.
The pad, wet and dry tanks, legs, fuel supply and electrical work can cost as much again as the dryer. When you compare a grain dryer for sale, quote the installed system. Start with dryer dealers and manufacturers on FarmPages and ask each the same questions.
8 Pre-Season Dryer Checklist
Work through this in August, not the night the wet bin fills.
- Clean fines, chaff and nests from columns, plenum and burner — debris fuels dryer fires
- Check the gas train and regulators for leaks with soapy water, never a flame
- Test flame sensing, high-limit and airflow safety switches
- Lock out power, then check fan blades, bearings and belts
- Run metering rolls and unloading empty and listen for worn bearings
- Calibrate moisture sensors against a handheld tester and an elevator sample
- Confirm propane is booked and the tank full, or gas pressure is ready
- Test remote alarms for shutdown and overheating
- Empty, clean and aerate wet and dry bins
- Put charged extinguishers in reach and walk the crew through emergency shutdown
Tip: log moisture in and out, plenum temperature and bushels per hour for each crop. After one season you’ll know your dryer’s real capacity.
Pricing a new dryer or retrofit? Compare grain drying suppliers on FarmPages, browse grain systems suppliers for bins and aeration, or start with our roundup of grain system suppliers on the Prairies.
Grain Drying FAQ
What size dryer do I need for my farm?
Estimate how many bushels a day will come off tough or damp in a wet year, divide by about 20 running hours, and add 20 to 25 percent headroom. Then ask dealers for capacity at your crop and typical points of removal, not the headline corn rating. Most Prairie wheat and canola farms size on 3 to 5 points removed.
Is a mixed flow dryer better than a cross-flow dryer for canola?
For many Prairie farms, yes. A mixed flow dryer has no fine screens to plug with canola fines and dries more evenly at the gentler temperatures canola and malting barley need. Cross-flow column dryers cost less up front and work well on corn and cereals, but need frequent cleaning when drying canola.
Can natural air drying replace a heated dryer on the Prairies?
In a moderate fall it often can, for wheat, barley or canola harvested a few points tough, if the bins deliver around 1 cfm per bushel or more. Drying nearly stops once air temperatures drop toward freezing, so in a cold, wet harvest most farms still want a batch or continuous dryer as backup.
Is propane or natural gas cheaper for drying grain?
Per unit of heat, natural gas is usually much cheaper than propane wherever a line reaches the yard. The catch is the cost of bringing service in and any fixed utility charges. Run the math with your own rates: pounds of water removed times about 2,000 BTU per pound, divided by the BTU in a litre of propane or a gigajoule of gas.
What is the difference between a batch dryer and a continuous flow grain dryer?
A batch dryer fills with a set load, dries and cools it, then empties before the next batch, so output is capped by cycle time and each load needs attention. A continuous flow dryer takes wet grain in at the top and discharges dry grain at the bottom without stopping, which suits larger volumes and automated yards.