Vented harvest bins for nuts, onions and potatoes

Why we have no photograph here

We only show photographs of the real thing, and we haven't found one of vented bins in an onion or potato store that we can use. The drawing shows the bin's shape. Ask us for the maker's sheet for any bin we quote and it will show the vent pattern.

Idaho is the potato state among those we cover, with fruit and vegetable preserving at 7.6 times its national share of jobs. California's Central Valley, around Fresno and north to Sacramento, grows most of the country's almonds, walnuts and pistachios.

Bin or bulk pile

Many potato and onion growers store their crop in bulk piles, not bins. Bins come in where the crop is stored by lot or variety, where seed potatoes are kept apart, or where a shed handles many growers' crops. In those cases, a vented bin keeps each lot separate while the air still reaches it.

Nuts at the huller

Almonds, walnuts and pistachios go from the orchard to a huller and drier, then into storage. Dry nuts flow like grain, so the vents in a nut bin have to be small enough to keep the nuts in while still letting air through.

Curing and storage air

After harvest, potatoes are cured for a couple of weeks at mild temperatures and high humidity so their skins set and cuts heal, then cooled slowly for long storage. Onions are cured to dry their necks and outer scales. In both cases air has to move through the stack, so bins are spaced with gaps and set with vents in line with the fans.

Dirt and rocks

Potatoes and onions come out of the ground with soil, stones and vines attached. Harvesters shake most of it off, but some reaches the bin and wears its floor. Heavy-duty floors and ribs that let debris fall through last longer under that grit. Rinse bins between seasons so diseases carried in the soil, such as those causing rot, don't overwinter in them.

Order storage bins before the shed's first fill; a storage can't take more crop than it has bins for.

Seed potatoes

Seed growers keep each lot apart for certification, which is why seed storages use bins where commercial ones use piles. Mark bins by lot and field.

Sweet potatoes

Sweet potatoes are cured warm and humid for about a week after digging, then stored cooler for months. They bruise and skin easily, so growers in North Carolina, Mississippi and Louisiana prefer bins with smooth insides and moderate depth.