Shelves Needed
1
Cu Ft
2.2
Months
0.8
Temp
38°F
2.2 cu ft for 100 lbs of potatoes
38°F
90%
0.8 mo
25 lbs
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Inputs
Result
100 lbs / 45 lbs per cu ft = 2.22 cu ft. Medium shelf = 4.5 sq ft × 1.5 ft depth = 6.75 cu ft per shelf. Shelves = ceil(2.22 / 6.75) = 1. At 30 lbs/person/month for 4 people = 120 lbs/month, so 100 lbs lasts 0.8 months.
Inputs
Result
200 lbs / 40 lbs per cu ft = 5 cu ft. Large shelf = 8 sq ft × 1.5 ft = 12 cu ft. Shelves = ceil(5 / 12) = 1. At 30 lbs/person/month for 2 people = 60 lbs/month. 200/60 = 3.33 months, capped at 5-month shelf life = 3.3 months.
Most root vegetables store best at 32–40°F (0–4°C) with 90–95% humidity. Winter squash and onions are exceptions — squash prefers 50°F with 60% humidity, and onions prefer 35°F with lower 65% humidity to prevent sprouting.
| Produce | Temp (°F) | Humidity | Shelf Life |
|---|---|---|---|
| Potatoes | 38 | 90% | 6 months |
| Carrots | 32 | 95% | 5 months |
| Apples | 32 | 90% | 4 months |
| Onions | 35 | 65% | 6 months |
Storage capacity depends on shelf size and produce density. Potatoes store at about 45 lbs per cubic foot, while cabbage only packs at 25 lbs per cubic foot. A typical 8×10-foot root cellar with 4 shelving units can hold 800–1,200 lbs of mixed produce, enough for a family of 4 for 3–4 months.
Organize by temperature and humidity needs. Place coldest items (carrots, beets) on the lowest shelves near the floor where air is coldest. Store apples separately — they release ethylene gas that causes other produce to spoil faster. Keep onions and garlic in the driest area with good ventilation.
For a family of 4, a root cellar of 6×8 feet (48 sq ft) provides enough space for 6 months of root vegetables. A larger 8×10 foot cellar accommodates a full year’s harvest including canned goods. The minimum practical size is about 4×6 feet for basic potato and carrot storage.
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Last Updated: Mar 20, 2026
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