Greenhouse Food Yield Calculator
See how many pounds of vegetables your greenhouse can grow in a year, and how much of your family's food that covers.
Please note: these results are estimates
This calculator gives general estimates based on typical conditions and the information you enter. Real harvests depend on your climate, soil, the varieties you grow, pests and disease, watering, how often you replant and your growing experience. Your actual results may be different, so use these numbers as a starting point for planning, not a guarantee. Always follow the manufacturer's instructions, and talk to a qualified professional before making important decisions. Questions? Call us at 678-408-8222.
How it works
How much food can a greenhouse grow?
A well-tended greenhouse bed gives roughly 1 pound of vegetables per square foot each summer. A longer season, a heater for winter crops, and shelves or trellises that use the height of the greenhouse all add to that. Fruiting crops such as tomatoes and cucumbers weigh more per square foot than lettuce.
Pounds a year = Floor (sq ft) × Share used for beds × Season × Crop mix × Vertical growing
We compare the result with about 220 pounds of vegetables per person a year, which is the 2½ cups a day the USDA recommends. These are estimates: your results depend on your climate, your soil and how often you replant.
Planning a more self-reliant garden? Read our guide to going off the grid with a greenhouse.
Questions
Food yield FAQ
How much food can a 10 x 12 greenhouse produce?
With about 60% of the floor in beds and a spring-to-fall season, a 10 x 12 ft greenhouse can grow roughly 130 pounds of mixed vegetables a year. With a heater and year-round growing, that rises to around 190 pounds.
How big a greenhouse do I need to feed a family?
For most of a family of four's vegetables, plan on around 500 to 600 square feet of heated, year-round greenhouse, or more if you only grow from spring to fall. A smaller greenhouse still covers salad greens, herbs and summer crops.
What grows the most food in a greenhouse?
Tomatoes, cucumbers, peppers and pole beans give the most weight per square foot, especially when trained up trellises. Salad greens weigh less but can be cut again and again, and replanted every few weeks.
Can I grow food in a greenhouse in winter?
Yes. Cold-hardy greens such as spinach, kale and lettuce grow in an unheated greenhouse through much of the winter in mild areas. A small heater keeps it frost-free and lets you grow far more.
More tools
Other greenhouse calculators
- Heater Size CalculatorHow many BTUs it takes to keep your greenhouse warm on the coldest night.
- Heating Cost CalculatorWhat a winter of heating will cost with electric, propane or natural gas.
- Fan and Ventilation CalculatorThe exhaust fan CFM and vent openings that keep summer heat down.
- Snow Load CalculatorHow much the snow on your roof weighs and when to brush it off.
- Foundation CalculatorConcrete, gravel, pavers and lumber for your greenhouse base.
- Greenhouse Size CalculatorHow big a greenhouse you need for the plants you want to grow.
- Shade Cloth CalculatorThe right shade percentage and cloth size for your greenhouse.
- Grow Light CalculatorHow many grow lights it takes to give your plants enough light in winter.
- Rainwater CalculatorHow much rain your greenhouse roof can catch, and how many barrels you need.
Want a second opinion?
Tell us about your greenhouse and where you live, and we will help you get it right.
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