Interactive lesson

Grain containers, step by step

Interactive lesson: jar, bin, drum, chest or sack — what is food-safe, how to seal grain airtight and how to arrange your containers.

Free sample Chapters 1 and 2 (8 steps) are free. The full lesson comes with the Bins, barrels and sacks module. Already bought? Unlock

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The whole lesson as text

1. Which container for what

Most homes don't need a granary, just a few good containers.

Jars for seed — A 1–5 L glass jar for seed, beans, semolina and a little flour. It holds roughly 0.75 kg of wheat per litre.
Bins for flour — A 30 L metal bin holds roughly 22 kg of wheat. For flour, grain for the kitchen and feed mix.
A drum for grain — A 200 L drum (US 55 gal) holds roughly 150 kg of wheat or maize, a 120 L drum 85 kg.
Chest and sack — A galvanised chest of 300–1,000 L holds grain for the whole year. A sack is for transport and the short term.

Why: The container is the last line of defence against damp, mice, moths and weevils. A good one stops all of them and lasts ten years or more.

Barley and oats are lighter: a 200 L drum holds roughly 120–130 kg of barley and only 90–100 kg of oats.
A full 200 L drum weighs about 150 kg (330 lb). Decide in advance where it stands, because full, it isn't moving.

2. What a container must do

A grain container must be food-grade, dry and clean, with a lid that seals.

Food-grade only — Plastic marked as food-safe. Metal galvanised or stainless steel, unpainted inside.
A lid that seals — A lid with a rubber gasket, a clamp ring or a screw thread. Smooth inside, without seams where dust collects.
Never from chemicals — Containers that held fuel, oil, paint, solvents, pesticides or fertiliser are never used, even when washed. If you don't know what was in it, it's not for grain.
Second-hand drums — Wash a drum that held syrup, olives or honey with hot water and unscented soap, dry it open in the sun for 2–3 days and smell it.

Why: Moths and flour beetles get through a gap of half a millimetre. And chemical residues soak into plastic, and the grain takes them up from it.

On plastic in the UK and Ireland look for the glass-and-fork symbol or a "food safe" label; in the US and Canada, "food grade". HDPE (2) and PP (5) are good for grain.
The smell of sauerkraut or olives lasts for months: use such a drum for whole grain, not flour.