Getting a storage facility ready for the new crop includes several steps, among which: cleaning, servicing and repairs, and ensuring proper adjustments and placement of equipment.

By Nora Olsen and Phil Nolte, University of Idaho

Each step is important to collectively maintain quality of your stored crop. The cleaning process is a critical initial step in storage facilities that had tuber breakdown due to rot or “hotspots”, where tuber decay had occurred the previous storage season. 

Wash and Rinse

Before harvest, prepare the storage facility for receiving potatoes by eliminating foreign material. Clean up trash such as old tubers, duct tape, wood, metal and insulation inside the storage. After removing all visible foreign material, pass a magnet over the floor and in corners to collect remaining metal contaminants. Don’t forget about removing potato and unwanted material from the plenum and duct pipes. Removing 1-2 inches of dirt floor and replacing with non-potato soil is a step often difficult to accomplish in a timely manner and one that can be often overlooked.

“Exposure to sunlight would be a good final step in the cleaning of equipment or duct pipes, after they have been thoroughly washed and disinfected, but it is not a replacement for cleaning.”

Nora Olsen, Ph.D.,
Professor, ExtensionPotatoSpecialist
University of Idaho

Washing is probably best accomplished with a pressure washer using hot water and detergent. Soap-based detergents are often fairly effective disinfectants in their own right, but are particularly effective at dissolving dried potato sap or other residues that might be adhering to floors, walls or equipment. Thoroughly rinse all cleaned surfaces before disinfecting.

Beware of Biofilms

Duct pipes must be thoroughly cleaned as well, as simply setting them outside in the sun will not do an adequate job of cleaning. This is because the organisms that cause disease in potatoes are capable of surviving on storage surfaces and on equipment under some fairly harsh conditions. They do so in clumps or films of cells surrounded and protected by dried bacterial slime, dried plant sap or other materials.

These structures are referred to as “biofilms”. Biofilms not only allow some bacterial cells to survive, but can also be very difficult to dissolve and remove. That is why using a soap-based product is absolute critical in the cleaning step. Disinfection alone will not adequately clean a storage facility. Exposure to sunlight would be a good final step in the cleaning of equipment or duct pipes, after they have been thoroughly washed and disinfected, but it is not a replacement for cleaning.

Step by Step

Remove plant debris and foreign material

Replace the dirt floor surface

Wash and rinse the entire facility

Apply a disinfectant to all surfaces

Inspect the storage for any needed repairs

Replace worn equipment and components

Check, calibrate and/or replace all computerized sensors

Service the air system and check all fans for proper balance

Tape all duct seams to safeguard the designed ventilation 

Read the whole story, with more on inspection and repairs and ensuring the optimum air flow in the storage facility in Potato Business Digital, Q1-spring issue.