Home Garden vs Store Produce Cost Calculator

Inputs explained

Seed/seedling cost (per season)

What you spend each season on seeds, starts, or transplants. If you save seeds, this may be near $0.

Equipment cost and lifespan (seasons)

One-time purchases (raised beds, hoses, drip lines, trellises, tools). Because equipment lasts multiple seasons, the calculator spreads (amortizes) that cost across the number of seasons you expect to use it.

Water cost (per season)

Extra water cost attributable to the garden. If you irrigate from a metered supply, you can estimate this from your bill (added usage × $/unit). If you collect rainwater, this may be $0.

Expected yield (lbs per season)

Total pounds harvested across the season for the crops you’re comparing. Yield is usually the biggest driver of whether gardening is cheaper.

Store price per pound

The price you would otherwise pay for comparable produce (same variety/quality, organic vs conventional, in-season vs out-of-season).

Formulas (what the calculator is doing)

The model treats gardening costs as a seasonal total, then divides by your expected yield to estimate a homegrown cost per pound.

1) Amortized equipment cost per season

If equipment costs E and lasts L seasons, the seasonal equipment cost is:

2) Total garden cost per season

Let S be seed/seedling cost per season, W be water cost per season, and E/L be amortized equipment per season:

Total garden cost per season:

C_g = S + (E / L) + W

3) Homegrown cost per pound

If expected yield is Y (lbs/season), then:

Cost_per_lb_garden = C_g / Y

4) Store cost for the same quantity

If store price is P ($/lb), then buying Y pounds costs:

Cost_store_total = P × Y

5) Savings (or extra cost)

Compare total seasonal costs for the same number of pounds:

Savings = Cost_store_total − C_g

A positive number means the garden is cheaper (estimated savings). A negative number means the store is cheaper (estimated extra cost to garden).

Interpreting the results

• Garden cost per lb answers: “If I divide my seasonal costs by my harvest, what did each pound effectively cost me?”
• Store cost per lb is your comparison baseline (what you’d pay per pound elsewhere).
• Total seasonal comparison is often easier to feel: “Over this season’s harvest quantity, did I spend less or more?”

Because equipment is spread across multiple seasons, the first season may feel expensive upfront, but the model reflects the cost as if it’s used over its full lifespan. If you stop gardening early, your real cost per pound will be higher than the estimate.

Worked example (using the default inputs)

Suppose you enter:

• Seed/seedling cost S = $20
• Equipment cost E = $150
• Equipment lifespan L = 5 seasons
• Water cost W = $15
• Expected yield Y = 100 lbs
• Store price P = $2.50/lb

Step 1: Amortize equipment

E/L = 150/5 = $30 per season

Step 2: Total garden cost per season

C_g = 20 + 30 + 15 = $65

Step 3: Garden cost per pound

$65 / 100 = $0.65 per lb

Step 4: Store cost for 100 lbs

$2.50 × 100 = $250

Step 5: Estimated savings

$250 − $65 = $185

This example suggests that if you truly harvest 100 lbs and your costs match the inputs, your garden produce is substantially cheaper than buying the same weight at $2.50/lb.

Yield sensitivity comparison

Using the same costs as above (S=$20, E=$150, L=5, W=$15) and the same store price (P=$2.50/lb), changing yield changes the garden cost per pound dramatically.

Note: This table uses the calculator’s cost structure and assumes the same total seasonal cost regardless of yield. In real gardens, higher yields may require more inputs (water, amendments, pest control).

Assumptions & limitations (important)

• Labor/time is not included. Your time planting, weeding, watering, harvesting, preserving, and shopping for supplies can be substantial. If you want a “true cost,” assign an hourly value and add it as an extra seasonal cost.
• Land cost and property impacts are excluded. The model assumes you already have space (yard, patio, community plot). Rent, plot fees, or opportunity cost of space are not included unless you add them into equipment or seed costs.
• Soil amendments and fertility may be missing. Compost, fertilizer, mulch, potting mix, and soil tests can materially change the economics. Add them to seed/seedling cost if you buy them each season, or treat them as equipment if they last multiple seasons.
• Losses and variability are simplified. Pests, disease, weather, and timing can reduce harvest. If you’re uncertain, use a lower yield to stress-test your results.
• Quality equivalence is assumed. The store price you enter should match what you’d buy (organic vs conventional, specialty varieties, freshness). If your garden quality is higher, the “fair” comparison store price may also be higher.
• Preservation/waste is not modeled. If some harvest spoils or you discard trimmings, your effective edible cost per pound increases.
• Equipment lifespan is an estimate. If tools break earlier (or last longer), your amortized cost changes. Containers and irrigation components often wear faster in sun and freezing climates.

Informational only: prices, yields, and water rates vary by region and season. This tool is best for planning and comparisons, not exact budgeting.

FAQ

How do I estimate yield (lbs) if I’ve never gardened before?

Start conservative. Use small test plots, look up typical yield ranges for your crop and square footage, or weigh a few harvests and extrapolate. If you’re unsure, run the calculator at multiple yields (low/medium/high) to see the break-even point.

What should count as “equipment”?

Include durable items used across seasons: raised beds, containers, trellises, irrigation lines, hoses, tools, row covers, and grow lights (if used for starts). Consumables (fertilizer, compost, potting mix) usually fit better in seasonal costs.

How can I estimate water cost?

If your utility bills show cost per unit (gallon or cubic foot), multiply estimated garden usage by that rate. If you don’t know usage, estimate watering frequency and duration, then approximate gallons per minute for your hose/drip system.

Should I include compost, fertilizer, and pest control?

Yes, if you want a closer-to-real comparison. Add recurring purchases to seed/seedling cost per season. If you buy a long-lived item (e.g., compost bin, sprayer), you can treat it as equipment and amortize it.

Does this work for perennials (berries, fruit trees, herbs)?

It can, but perennials often have a high establishment cost and a ramp-up period before full production. Model a typical mature-year yield and spread establishment costs across more seasons, or run multiple scenarios (year 1 vs year 3+).