Harvest is wrapping up across the Wimmera, and grain storage decisions are front of mind. With on-farm storage capacity expanding—many growers now hold more than 60% of their harvest rather than delivering immediately—getting storage conditions right matters more than ever.

I spoke with three local growers about the sensor technology they’re using and what’s actually delivering value.

The Shift to Monitored Storage

Traditional grain storage relied on periodic manual checks—opening hatches, using probe thermometers, and watching for condensation or insect activity. That approach worked, but problems often went undetected until visible damage occurred.

Modern sensors continuously monitor temperature and relative humidity at multiple points in a silo. Data transmits to a phone app or computer, alerting growers when conditions change.

“I used to drive out to check silos twice a week during summer,” says Michael, who farms near Horsham. “Now I check the app from my kitchen. I only visit when something needs attention.”

Hardware Options in Use

Three main sensor brands appeared in my conversations with local farmers:

OPI Systems (Integris)

The most established option, with temperature cables installed during silo construction. Most expensive upfront but considered the most reliable for large permanent installations.

“We put Integris in our main battery when we built it seven years ago,” one grower near Nhill told me. “Haven’t had a single hardware failure.”

GrainWave

Australian-made sensors that attach magnetically to silo walls. Lower upfront cost and don’t require installation inside the silo.

“I like that I can move them between silos depending on what’s full,” says Rebecca, who manages grain storage for her family’s operation near Stawell. “We’ve got 12 silos but usually only have 6-8 full at any time.”

The Grain Spy

Wireless sensors that insert through the silo lid. Mid-range price with good mobile app integration.

Each option involves trade-offs between cost, installation complexity, and features. None emerged as a clear “best”—it depends on your specific setup.

What the Data Actually Shows

The real value isn’t just knowing current conditions. It’s spotting trends before they become problems.

“Last March I noticed one silo’s temperature trending up while others stayed stable,” Michael said. “Turned out we had a small moisture pocket near the wall. Ran the aeration for 48 hours and it stabilised. Without the sensors, I wouldn’t have caught it until we saw insect activity.”

Temperature spikes often indicate insect activity. A 3-4°C rise in one section while ambient temperatures stay stable is a warning sign. Early detection means treatment options are simpler—often just running aeration rather than fumigating or moving grain.

Connectivity Challenges

The Wimmera’s mobile coverage remains patchy. Sensors that rely on direct 4G transmission don’t work everywhere.

Solutions growers are using:

• Mesh networks: Sensors communicate to a central hub with better connectivity
• Satellite backup: Some systems offer satellite transmission as fallback
• Data logging: Store readings locally and sync when connectivity available

“We’ve got a repeater on the shed that picks up signal from the house, then broadcasts to sensors on the back paddock,” explains one grower near Warracknabeal. “Bit of mucking around to set up but works reliably now.”

NBN Co has expanded fixed wireless coverage across parts of the region, which helps for silos near the homestead. But for storage further out, mobile connectivity remains the main hurdle.

Cost Reality

Expect to pay:

• Basic sensor system (4-6 silos): $2,000-4,000
• Premium system with multiple sensors per silo: $6,000-12,000
• Ongoing connectivity/subscription: $200-500 per year

Most growers said the investment paid for itself within 2-3 seasons through reduced grain losses and lower monitoring labour.

Common Setup Mistakes

What I heard about things that went wrong:

1. Placing sensors too high: Heat rises, so top sensors show highest readings. But most problems start lower where moisture collects.

2. Not calibrating for silo type: Metal silos behave differently than concrete. Settings that work for one may not work for another.

3. Ignoring aeration integration: The best setups trigger aeration automatically when thresholds are exceeded. Manual-only systems mean you’re still making midnight trips.

4. Underestimating battery life: Some wireless sensors need battery changes every 6-12 months. Budget for this and set calendar reminders.

What Growers Wish They’d Known

“I wish I’d started with just two silos properly set up rather than trying to cover everything at once,” Rebecca reflected. “You learn what matters, then you can expand.”

Michael’s take: “Talk to someone local who’s been using sensors for a few years. The company reps know the product but they don’t always know Wimmera conditions.”

The Birchip Cropping Group has run workshops on storage technology and can connect growers with experienced users.

Looking Ahead

Several growers mentioned interest in predictive systems that combine weather forecasts with silo data to recommend aeration schedules. This kind of AI application is starting to appear in the market, though adoption in the region is still limited.

For now, the fundamentals matter most: reliable sensors, good connectivity, and knowing what the numbers mean for your specific grain and storage setup.

The technology is mature enough that it’s no longer experimental. For any grower holding significant on-farm storage, sensors have moved from “nice to have” to essential infrastructure.