The True Cost of Compost:
An Analysis of Bagged vs. Bulk Compost Prices
Compost is one of the most common and beneficial garden amendments — but are you always getting what you pay for? The costs of compost, whether bagged or in bulk, vary widely, and to help you get the best value, we’re sharing this analysis completed by our friends at Woods End Laboratories. These calculations show that buying loads of bulk compost and hauling them in a pick-up truck can save you a ton of money! (See the yellow column in the second chart below for estimates of your savings.)
The Cost of Bagged Compost
| Tons/acre | Cubic yards/acre | Lbs./100 square feet | Inches of depth | Bags* per/100 square feet | Cost if priced at rate per bag** | Cost of compost 20-by-40 feet | Required bags per garden | Trips to garden center | Car travel costs^ | TOTAL bagged compost cost |
| 200 | 500 | 910 | 3.7 | 22 | $131.78 | $1,054.24 | 176 | 22 | $148.50 | $1,202.74 |
| 100 | 250 | 450 | 1.8 | 11 | $65.89 | $527.12 | 88 | 11 | $74.25 | $601.37 |
| 75 | 180 | 340 | 1.3 | 8 | $47.92 | $383.36 | 64 | 8 | $54.00 | $437.36 |
| 50 | 120 | 220 | 0.8 | 5 | $29.95 | $239.60 | 40 | 5 | $33.75 | $273.35 |
| 25 | 60 | 110 | 0.4 | 2 | $11.98 | $95.84 | 16 | 2 | $13.50 | $109.34 |
| 10 | 20 | 40 | 0.1 | 1 | $5.99 | $47.92 | 8 | 1 | $6.75 | $54.67 |
These calculations assume a density of 800 lbs. per cubic yards of compost.
*40 lbs. per bag = 1.5 cubic feet each (12 QTs)
**Typical Maine bagged compost price at retail outlet
^Assumes 15 mile roundtrip at $0.45 per mile
The Cost of Bulk Compost
| Tons/acre | Cubic yards/acre | Lbs./100 square feet | Inches of depth | Pick-up loads | Cost of compost | Pick-up travel costs | TOTAL bulk compost cost | TOTAL cost savings compared with bagged compost |
| 200 | 500 | 910 | 3.7 | 9 | $450.00 | $60.75 | $510.75 | $691.99 |
| 100 | 250 | 450 | 1.8 | 4 | $200.00 | $27.00 | $227.00 | $374.37 |
| 75 | 180 | 340 | 1.3 | 3 | $150.00 | $20.25 | $170.25 | $267.11 |
| 50 | 120 | 220 | 0.5 | 2 | $100.00 | $13.50 | $113.50 | $159.85 |
| 25 | 60 | 110 | 0.4 | 1 | $50.00 | $6.75 | $56.75 | $52.59 |
| 10 | 20 | 40 | 0.1 | 0.4 | $18.37 | $2.48 | $20.84 | $33.83 |
Assumes a bulk compost cost of $50 per yard
According to these figures, bagged compost needs to be priced at or less than $2.25 per bag to compete with the cost of hauling your own compost puchased in bulk. For details on making your own compost at home and saving even more money, check out our article Compost Made Easy.
Bagged compost photo from iStockphoto; bulk compost photo from Fotolia
