Calculator Inputs
Example Data Table
| Scenario | Household | Area m² | Crop mix | Stored calories | Expected result |
|---|---|---|---|---|---|
| Balcony starter | 2 people | 8 | Greens, herbs, tomatoes | 50,000 | Low calorie coverage, high fresh food value |
| Rooftop staple plan | 4 people | 75 | Potatoes, beans, carrots | 250,000 | Moderate coverage with useful storage planning |
| Community plot | 6 people | 160 | Staples, greens, squash | 600,000 | Strong seasonal supply with reserve potential |
Formula Used
Base need = household size × daily calories per person × planning days.
Reserve calories = household size × daily calories per person × reserve days.
Adjusted need = base need + reserve calories.
Gross crop weight = area × yield per m² × crop cycles.
Usable crop weight = gross weight × edible percent × (1 − crop loss percent).
Crop calories = usable crop weight × calories per kilogram.
Usable available calories = (crop calories + stored calories) × (1 − household waste percent).
Self sufficiency percent = usable available calories ÷ adjusted need × 100.
Purchase kilograms = calorie gap ÷ backup food calories per kilogram.
Extra area needed = target calorie gap ÷ average crop calories per m².
How to Use This Calculator
- Enter the number of people in the household.
- Add daily calorie needs and the length of the plan.
- Enter reserve days for emergency or seasonal storage.
- Add current stored calories from pantry food.
- Set waste, backup food, storage, and water assumptions.
- Fill each crop row with area, yield, cycles, edible share, calories, and loss.
- Press the calculate button and review the result above the form.
- Use the CSV or PDF button to save the result.
City Harvest Self Sufficiency Planning Guide
Measure Food Independence
A city harvest self sufficiency calculator helps turn small gardens into measurable food plans. It connects household demand with the real output of raised beds, balcony boxes, rooftops, and shared plots. The goal is not guesswork. The goal is a clear estimate of how much food your space can supply.
Start With Demand
Urban food planning starts with calories. A household needs a certain number of calories each day. The calculator multiplies people, daily calories, and planning days. It then adds a reserve period. This creates a practical target for storage and production. Stored food is included, because a pantry can close many seasonal gaps.
Compare Crop Output
Crop yield is the second part. Each crop has area, yield, cycles, edible portion, loss rate, and calories per kilogram. These details matter. Lettuce may give high weight, yet low calories. Potatoes may need more space, but add useful energy. Herbs improve meals, but do not replace staple calories. The calculator shows these differences with one combined result.
Account For Loss
Losses are important in city systems. Harvests can shrink through pests, trimming, spoilage, heat, and kitchen waste. A small percentage can change the final answer. That is why the tool separates crop loss from household waste. It gives a more honest view of usable food.
Improve The Plan
The result helps you choose better actions. A low self sufficiency score may suggest more staple crops, extra containers, or stronger storage. A high score may show that your garden can cover many weeks. The gap figure helps estimate purchases. The area estimate shows how much more growing space may be needed.
Test Different Seasons
This calculator is also useful for comparing plans. You can test a rooftop tomato plan, then switch to beans or potatoes. You can add another crop cycle. You can adjust reserve days before winter. Each version creates a clearer food strategy.
Use Results Carefully
Use the numbers as planning guides, not promises. Weather, soil, watering, seed quality, and care affect results. Local advice should guide final crop choices. Still, a structured estimate is powerful. It helps households plan resilient harvests, reduce waste, and understand their true city food independence.
Review Often
Families can repeat the calculation each season. Saved results make targets easier to review. Over time, the garden becomes a tested food system, not a hopeful guess.
FAQs
What does city harvest self sufficiency mean?
It means the share of household food demand covered by urban harvests and stored food. This calculator measures that share with calories, crop weight, losses, and reserve needs.
Can this calculator work for balcony gardens?
Yes. Enter the balcony growing area and realistic yields. Small spaces may show low calorie coverage, but they can still provide valuable fresh produce.
Why are calories used instead of only kilograms?
Kilograms can mislead. Leafy greens weigh a lot but offer fewer calories. Staple crops may weigh less but provide more energy for self sufficiency planning.
What is crop loss percent?
Crop loss covers waste before food is usable. It may include pests, trimming, spoilage, poor harvest timing, or damaged produce.
How should I estimate yield per square meter?
Use local garden records, seed guides, extension data, or conservative past results. Lower estimates are safer for planning household resilience.
What does extra area needed show?
It estimates how much additional growing space may be needed to hit your target. It uses your current average calories per square meter.
Can stored pantry food improve the result?
Yes. Stored calories are added to crop calories before household waste is applied. This shows how pantry reserves can close seasonal gaps.
Should I treat the result as exact?
No. It is a planning estimate. Weather, soil quality, watering, pests, seed choice, and care can change actual harvest output.