A freezer lets you harvest at peak production and eat your garden through December. What it doesn’t do is free. There’s a purchase price, an electricity cost, and a per-bag overhead that most gardeners never calculate. The question isn’t whether a garden freezer is worth having - it usually is. The question is whether you’re big enough to justify one, or whether you’re better off sharing freezer space with a neighbor.
This is the actual math. Chest freezer cost broken down to a per-year number, electricity cost from DOE data, per-bag overhead from first principles, and the retail frozen price comparison by crop. At the end, a break-even table for three garden sizes.
The Freezer Itself
Chest freezers are more efficient than upright models because cold air doesn’t fall out when you open the lid. For garden preservation, a 7 to 9 cubic foot chest freezer is the standard recommendation - big enough to hold a serious surplus but small enough to manage. Prices:
| Size | Price Range | Typical Lifespan |
|---|---|---|
| 5 cu ft chest | $120-$180 | 15-20 years |
| 7 cu ft chest | $150-$220 | 15-20 years |
| 9 cu ft chest | $180-$270 | 15-20 years |
| 15 cu ft chest | $250-$380 | 15-20 years |
ENERGY STAR-certified models use less electricity and typically carry longer warranties. The upfront cost difference between standard and ENERGY STAR is usually $20 to $40. Over 15 years of electricity bills, that difference pays back 3 to 5 times.
Using a 7 cu ft chest freezer at $185 purchase price and a conservative 15-year lifespan:
Amortized purchase cost: $185 / 15 years = $12.33 per year
If the freezer lasts 20 years (realistic for quality units), that drops to $9.25 per year.
Electricity Cost
The US Department of Energy’s ENERGY STAR program tracks chest freezer energy use by size. A 7 cubic foot ENERGY STAR chest freezer uses approximately 150 to 200 kilowatt-hours per year under typical conditions (DOE ENERGY STAR Certified Residential Chest Freezers, 2024 data). Non-certified models in the same size class use 200 to 280 kWh per year.
The US average residential electricity rate is approximately $0.16 per kWh as of 2024 (US Energy Information Administration, Electric Power Monthly, December 2024). Regional rates range from $0.10 per kWh in the Pacific Northwest (hydropower states) to $0.25 to $0.30 in New England and Hawaii.
| Freezer type | Annual kWh | At $0.16/kWh | At $0.10/kWh (low) | At $0.25/kWh (high) |
|---|---|---|---|---|
| 7 cu ft ENERGY STAR | 175 kWh | $28/yr | $17.50/yr | $43.75/yr |
| 7 cu ft standard | 240 kWh | $38.40/yr | $24/yr | $60/yr |
| 9 cu ft ENERGY STAR | 200 kWh | $32/yr | $20/yr | $50/yr |
At national average rates, a 7 cu ft ENERGY STAR model runs $28 to $32 per year in electricity.
Total annual fixed cost (7 cu ft ENERGY STAR at $0.16/kWh):
- Amortized purchase: $12.33
- Annual electricity: $28.00
- Total: $40.33 per year
The Per-Bag Cost
Beyond the fixed annual cost, each bag of frozen produce has a small marginal cost: the freezer bag itself, and the incremental electricity to cool that new addition.
A box of 28 gallon-size freezer bags costs $5 to $8, putting the per-bag cost at $0.18 to $0.29. A box of 20 quart-size bags runs $3 to $5, or $0.15 to $0.25 per bag. Reusable silicone bags cost $8 to $15 each but amortize to near-zero over dozens of uses.
The electricity to freeze a fresh gallon of produce (lowering it from 40°F to 0°F) is small - approximately 0.03 to 0.05 kWh per pound of product, adding $0.005 to $0.008 per pound at national average rates. Rounding up to $0.01 per pound, a 2 lb bag of frozen green beans costs roughly $0.02 in incremental electricity to freeze.
Per-bag total variable cost:
| Approach | Per bag |
|---|---|
| Disposable gallon freezer bag | $0.18-$0.29 |
| Disposable quart bag | $0.15-$0.25 |
| Reusable silicone (amortized) | $0.05-$0.10 |
| Incremental electricity (2 lb bag) | $0.02 |
If you freeze 80 bags per season using disposable gallon bags at $0.23 average:
- Variable cost: 80 bags × $0.23 = $18.40
- Fixed cost: $40.33
- Total season cost: $58.73
- Cost per bag (all-in): $0.73
At 120 bags per season, fixed costs amortize further: total $68.13, or $0.57 per bag all-in.
What Retail Frozen Produce Actually Costs
This is what your frozen garden produce is competing against. Prices from USDA Agricultural Marketing Service terminal market and retail price data (2024 averages):
| Crop | Retail frozen price/lb | Notes |
|---|---|---|
| Green beans | $2.50-$3.50 | Cut or French-style; whole pod premium |
| Spinach | $3.00-$5.00 | Chopped; whole leaf commands higher price |
| Sweet corn (kernels) | $2.00-$3.50 | Off-cob; comparable to store bag |
| Broccoli | $2.50-$4.00 | Florets; stalks not counted |
| Peas (garden) | $2.50-$4.00 | Shelled |
| Zucchini (shredded) | $3.00-$5.00 | Specialty item; limited retail availability |
| Tomatoes (crushed/diced) | $2.00-$4.00 | Equivalent to retail canned diced |
| Winter squash (puree) | $2.50-$4.00 | Specialty; butternut puree |
| Peppers (diced) | $4.00-$6.00 | Bell pepper strips/diced |
| Herbs (frozen) | $8.00-$16.00 | Basil, cilantro, chives in cube/pack form |
Herbs deserve special mention. A pound of frozen basil cubes retails for $10 to $16 at specialty grocers and online. Growing 4 basil plants (typical in a 4x8 bed) and processing the end-of-season surplus yields approximately 0.5 to 1 pound of frozen basil. That $8 to $16 retail equivalent costs roughly $0.50 to $0.75 in bag and freezer overhead. The return ratio is 10 to 20:1.
The Freeze Value Per Bag
Working from retail prices and typical harvest densities:
| Crop | Fresh lbs per gallon bag | Retail frozen value | All-in freeze cost | Net value/bag |
|---|---|---|---|---|
| Green beans | 2 lb | $5.00-$7.00 | $0.73 | $4.27-$6.27 |
| Spinach (blanched/compressed) | 1.5 lb | $4.50-$7.50 | $0.73 | $3.77-$6.77 |
| Corn kernels (cut from cob) | 2 lb | $4.00-$7.00 | $0.73 | $3.27-$6.27 |
| Broccoli | 1.5 lb | $3.75-$6.00 | $0.73 | $3.02-$5.27 |
| Zucchini (shredded) | 2 lb | $6.00-$10.00 | $0.73 | $5.27-$9.27 |
| Diced peppers | 1.5 lb | $6.00-$9.00 | $0.73 | $5.27-$8.27 |
| Basil (chopped, blanched) | 0.5 lb | $4.00-$8.00 | $0.73 | $3.27-$7.27 |
The $0.73 all-in freeze cost (at 80 bags, disposable bags) is low enough that it essentially doesn’t change the value calculation. The question is whether you have the surplus to freeze.
Break-Even at Three Garden Sizes
How much freezer overhead can your garden justify? Break-even assumes the garden produces surplus beyond fresh use, and that frozen produce actually gets eaten (not forgotten in the back of the freezer for two years).
Small garden: 1 four-by-eight bed (32 sq ft)
A single well-planted 4x8 bed with two tomato plants, some green beans, zucchini, basil, and lettuce will generate approximately 15 to 30 pounds of freezable surplus in a good year. Most of that is zucchini and tomatoes in August and September.
- Freezable surplus: 15-30 lb (7-15 gallon bags)
- Retail equivalent value: $45-$120
- All-in freeze cost (7-15 bags at $0.73 + $40.33 fixed): $45-$51
- Net value of freezing: $0 to $70
At the low end of surplus (7 bags, $45 retail value), the fixed costs of the freezer eat the entire benefit. A single bed doesn’t generate enough volume to justify a dedicated freezer. Recommendation for single-bed gardens: use existing refrigerator/freezer space or share freezer space.
Medium garden: 2-3 beds (64-96 sq ft)
Two or three beds with a more intentional preservation strategy - a dedicated bean succession for freezing, extra zucchini, a tomato paste batch - generate 50 to 90 pounds of freezable surplus.
- Freezable surplus: 50-90 lb (25-45 gallon bags)
- Retail equivalent value: $150-$350
- All-in freeze cost (25-45 bags × $0.23 + $40.33 fixed): $46-$51
- Net value of freezing: $100-$300
At this size, the freezer starts pulling its weight clearly. Fixed costs are a smaller portion of total value, and the preservation ROI is 2:1 to 6:1. This is the entry point where a dedicated chest freezer makes economic sense.
Large garden: 4+ beds (128+ sq ft)
A serious 4-bed operation with intentional surplus crops - green beans for blanching and freezing, a full row of winter squash, a dozen tomato plants - produces 100 to 250 pounds of freezable surplus.
- Freezable surplus: 100-250 lb (50-125 gallon bags)
- Retail equivalent value: $300-$900
- All-in freeze cost (50-125 bags × $0.23 + $40.33 fixed): $52-$69
- Net value of freezing: $230-$830
At this scale, the freezer is clearly profitable. Fixed costs represent 5 to 20 percent of the retail value preserved. A 9 cu ft or larger chest freezer is justified; two chest freezers are justifiable for a large homestead operation.
| Garden size | Freezable surplus | Retail value | Freeze cost | Net |
|---|---|---|---|---|
| Small (1 bed, 32 sq ft) | 15-30 lb | $45-$120 | $45-$51 | $0-$70 |
| Medium (2-3 beds, 64-96 sq ft) | 50-90 lb | $150-$350 | $46-$51 | $100-$300 |
| Large (4+ beds, 128+ sq ft) | 100-250 lb | $300-$900 | $52-$69 | $230-$830 |
What Actually Makes the Math Work
Two things determine whether a garden freezer pays off: volume and crop selection.
Volume is straightforward - the larger your surplus, the better fixed costs amortize. The first 20 bags you freeze effectively cost $2 to $2.50 each when fixed costs are allocated. The 100th bag costs $0.60.
Crop selection matters more than gardeners expect. Freezing green beans or spinach - crops with 3 to 4:1 fresh-to-retail frozen value ratios - returns solid value per bag but requires significant volume to justify. Freezing herbs, peppers, and zucchini - crops with 8 to 15:1 value ratios when frozen - justify the freezer cost with far less volume. If you’re going to have a small garden and a dedicated freezer, plant what freezes at premium value.
For how freezing compares to canning as a preservation method, see Freezing vs. Canning. For the full economics of home canning, see The Financial Case for Canning. The green bean section of the green bean growing guide covers harvest timing for maximum freeze quality.