The Rise of Rooftop Gardening

In dense cities where land is scarce, rooftop gardens provide fresh produce and green space. A well-planned roof plot can supplement household groceries or supply a small community-supported agriculture program. To maximize your harvest, you need to know how much edible crop the space can realistically produce. That’s where this calculator comes in.

How Yield Is Calculated

The total annual yield depends on area, planting density, and the number of harvest cycles. Mathematically, it’s expressed as:

where $A$ is the roof area in square feet, $C$ is the percent of that area allocated to planters, $D$ is the expected yield per square foot in pounds, and $H$ is the number of harvests per year. The formula helps you experiment with different layouts or crop varieties to see how they affect output.

Sample Calculation

Suppose you have 500 sq ft of space, but only 80% will hold planters. With an average yield of 0.7 lb per square foot and two harvests per year, your annual harvest would be:

That’s about 560 pounds of produce each year—plenty for salad lovers and neighborhood sharing.

Tips for Productive Rooftop Gardens

Choose lightweight containers and soil mixes to avoid overloading your roof structure. Drip irrigation and mulching help conserve water, especially during hot summers. Rotate crops between harvests to maintain soil health and vary your diet. Tracking yields over time allows you to refine your planting strategy.

Conclusion

Urban farming turns unused rooftops into productive spaces. With this calculator, you can set realistic expectations for the amount of fresh produce you’ll enjoy each season.