How to calculate mushroom cost per pound: tent, room and microfarm

To work out cost per pound, add up your blocks or substrate, your running costs, a share of your equipment, and your time if you want a farm number. Then divide by the fresh pounds harvested in the same period:

Cost per pound = (blocks or substrate + power, water and supplies + equipment cost ÷ months you expect to use it + hours worked × your hourly rate) ÷ fresh pounds harvested

Work it over one month, so the equipment term is that month's share. Count every block you started, including the ones you threw out, so that losses show up in the result.

The formula, one term at a time

• Blocks or substrate. Ready-to-fruit blocks you buy, or the substrate, spawn and bags you make them from.
• Running costs. Electricity, water, and supplies such as gloves, alcohol and filters. A device's electricity is its kilowatts × hours run × your rate. The US average residential rate was 18.31 cents per kWh in July 2026 (EIA).
• Equipment. Divide what a tent, room, pressure canner or lab cost by the months you expect it to last. That spreads it across the pounds it helps you grow.
• Your time. Leave it out for a hobby number. Put it in for a farm number, at the hourly rate you'd pay someone else.

A per-block version is quicker when you compare blocks or strains:

Cost per pound ≈ cost per block ÷ (fresh pounds per fruiting block × share of blocks that fruit)

This guide uses fresh pounds, the weight on the scale at harvest. If you dry your harvest, the last section shows how a dry pound compares.

What does one 5-lb block cost?

A 5-lb block costs $18–35 ready to fruit, about $22 as a bought sterilized bag you spawn yourself, and about $5–6 made from pellets. At list prices, a sterilized bag costs more than a block from an 8-pack. Pellets are the cheap route, but they add your time and sterilizing.

Route	What you buy	Cost per block
Ready to fruit	Blue oyster block: $34.99 alone, $24.75 each in a 4-pack, $18 each in an 8-pack	$18–34.99
Sterilized bag, your spawn	5-lb bag of sterilized Master's Mix, $19.99; 5-lb bag of blue oyster grain spawn, $29.99, which covers 12–13 bags	about $22.30–22.50 (about $15 on sale)
Make it from pellets	1.75–2 lb of Master's Mix pellets at $47.99 for 40 lb; one filter-patch bag at $36.99 for 50; spawn as above	about $5.15–5.65 (about $4.80–5.20 with spawn on sale), plus sterilizing

Prices are from the vendors' own pages on 19 October 2026. North Spore sells its blue oyster block for $34.99 alone, or $18 each in an 8-pack (North Spore — affiliate link: we may earn a commission at no extra cost to you). The other prices are Midwest Grow Kits'. Its sterilized bag and spawn were on sale that day for $12.99 and $24.99, so the table gives list prices first (sterilized bag, spawn). Its pellets are a 50/50 blend of oak and soy hull, and its filter-patch bags hold 5–6 lb (pellets, bags).

A few notes on the cheaper routes:

• Pellets per block. A 5-lb block hydrated to 60–65% water holds 1.75–2 lb of dry substrate. A UC Cooperative Extension handout hydrates its 5-lb sawdust blocks to 65% moisture, and cites Stamets' 60–65%. Pellets hold a little water of their own, so weigh out slightly more. The handout's 65% recipe takes about 2 lb of ingredients, as bought, for 1.75 lb dry (UC Cooperative Extension).
• Spawn comes in whole bags. One 5-lb bag covers 12–13 blocks, so a smaller batch pays for spawn it can't use. Our liquid culture syringe guide covers inoculating your own grain, which shrinks this line.
• Sterilizing. Midwest Grow Kits recommends 3.5 hours at 15 PSI for Master's Mix. On an electric burner, the energy is the burner's kilowatts × hours × your rate, split across the bags in the load. A 1.5 kW burner running 3.5 hours at pressure uses 5.25 kWh, about 96 cents at 18.31 cents per kWh. Heat-up time adds to that.
• The canner. A pressure canner is equipment, not a block cost. Presto's 23-quart canner costs $185.99 (Presto), so spread it over the months you'll use it.

Making blocks swaps money for time. In a USDA-funded SARE study of five mushroom farms, farms that made their own blocks spent 80% of operating costs on labor. Farms that bought ready-to-fruit blocks spent 58% on materials (SARE).

How many pounds does a 5-lb block give?

A 5-lb block gave about 0.7–1.6 lb of fresh mushrooms per block started in the SARE study, depending on the farm and how long blocks stayed in. The five farms averaged 0.88 lb per 5-lb block they started, counting lost blocks, and ranged from 0.66 to 1.17 lb. Cornell's trial blocks, left to fruit for 8 weeks, gave 1.36–1.63 lb. Most farms rotate blocks out every 2–4 weeks instead (SARE).

Biological efficiency (BE) lets you compare blocks of different sizes and recipes. BE is the fresh weight of the mushrooms divided by the dry weight of the substrate, as a percentage (PMC). A UC Cooperative Extension guide gives oysters 100–200% and shiitake 50–145% (UC Cooperative Extension).

To turn BE into pounds, multiply it by the block's dry weight. That's a little less than the weight of pellets or dry ingredients you measured before adding water, since they hold some moisture of their own. At 65% moisture, a 5-lb block holds 1.75 lb of dry substrate, so 50% BE is about 0.9 lb and 100% is 1.75 lb. By that arithmetic, SARE's 0.88 lb per block started is about 50% BE with lost blocks already counted. Cornell's blocks reached about 78–93%.

How much do yield and lost blocks matter?

Yield and lost blocks move cost per pound as much as the block price does, because a lost block's cost lands on the blocks that fruit. The table is illustrative arithmetic, not a benchmark. It assumes an $18 block holding 1.75 lb of dry substrate, and loss rates you should replace with your own.

Each cell is $18 ÷ (fresh pounds per fruiting block × (1 − share of blocks lost)).

SARE's 0.88 lb already counts lost blocks, so compare it with the None lost column, not the loss columns.

For example, at 75% BE a fruiting block gives 1.75 × 0.75 = 1.3125 lb. With 10% of blocks lost, each block started gives 1.3125 × 0.9 ≈ 1.181 lb. Then $18 ÷ 1.181 lb ≈ $15.24 a pound.

Two patterns hold for any block price. Doubling BE halves the cost per pound. Losing a quarter of your blocks raises every figure by a third. A $5 homemade block scales every cell to about 28%: at 75% BE with 10% lost, about $4.23 a pound before energy, equipment and time.

Tent, room or microfarm: what changes?

The formula is the same at every scale; what changes is which term is biggest. In a tent it's the blocks. In a room, the build starts to count. On the SARE study's microfarms, it was labor, on average.

In a tent

A tent adds little to each pound. Our Martha tent guide prices a tent at about $150–480 to set up and about $5 a month to run. Its worked example finds the tent and power come to only about $1.50–2.50 of each pound. So at tent scale, the block table and the yield table above are most of your answer.

In a room

A room's build cost becomes a real term, and published builds vary widely:

Build	What the cost covers	Cost
Fruiting room inside an existing farm building, North Carolina, 2022–23	Materials, plus specialized labor	$3,773.91 + $5,920
Growing space inside a greenhouse structure, Georgia, 2022–23	Infrastructure materials, not itemized in the report	$10,043.86
Insulated shipping container, North Carolina, 2022–23	Container, HVAC, electrical and build-out, plus blocks, packaging, storage and other costs	$33,577.26
Cold storage	An air conditioner and CoolBot controller only, fitted to an insulated space you already have (old walk-in cooler, reefer trailer or built room)	about $1,000

The first three rows are from Transfarmation grant reports by farmers moving out of animal farming (hog farm, greenhouse, container). The hog-farm room was finished, but its report says the farmer didn't follow the construction recommendations, and a site visit found environmental-control flaws. The Georgia report doesn't itemize its infrastructure line, and that project is on hold. The container build was budgeted at $18,131.54. Its farmer's main lesson was that material and trailer prices "can fluctuate dramatically" during a project. The cold storage figure is from a Cornell Small Farms and Fungi Ally guide (Cornell Small Farms and Fungi Ally).

A build's share of each pound depends on how much the room grows. Two of the Transfarmation proposals budgeted $10,000 for a 10 x 20 ft cultivation chamber. If a build like that lasts five years, it costs about $167 a month:

• At 15 lb a week, the smallest output among the five SARE farms, it adds about $2.56 a pound.
• At 95 lb a week, the five farms' average, about $0.41.
• At 150 lb a week, which the Cornell and Fungi Ally guide says an 8 x 16 ft room can grow, about $0.26.

A room also runs heating, cooling, humidifiers and fans. Price each one the same way: kilowatts × hours a month × your rate.

On a microfarm

Labor was the largest operating cost across the five SARE farms, averaging 67% against 32% for materials, with labor counted at $15 an hour. The report adds that in most farm enterprises, labor is the highest cost (SARE).

SARE farms, 2020 (5-lb block equivalents)	Operating cost per block	Labor per block
All five farms	$10.22	0.51 hours
Top four by output	$6.43	0.25 hours
Top three by output	$5.33	0.22 hours

Operating cost here is materials plus labor. Divided by each group's pounds per block (0.88, 0.87 and 0.77), that's about $11.60, $7.40 and $6.90 a pound in operating cost. Farm by farm, it ran from about $3.40 to $27.30 a pound. Labor per block ran from 0.14 to 1.52 hours across the five farms, and averaged 0.56 hours per pound harvested. These are 2020 figures, so use the hours and shares more than the dollars.

SARE's operating costs also leave out equipment, buildings, rent and utilities. The Cornell and Fungi Ally guide, written from the same study, puts the farms' capital and fixed costs at $4,751.12 on average, from $694.85 to $10,665. The growers said they reported these less accurately than operating costs. Making your own blocks also adds a lab. The guide's mid-range lab budget is $8,190, with closer to $4,000 possible "depending on your knowledge, skill level, and time" (Cornell Small Farms and Fungi Ally).

How does Hypha work out cost per pound?

Hypha Pro and Farm work out cost per pound block by block, from the supplies, bought blocks and prep you record:

1. Inventory. Add supplies, and any blocks you buy ready to grow, with what you paid. When you restock at a new price, Hypha keeps a weighted-average unit cost.
2. Prep. When you log a prep run from a recipe, enter what the run cost. Hypha suggests a total from the recipe's priced supplies, and splits it evenly across the run's outputs. Bought blocks skip this step.
3. Blocks. Start a block from prepped stock, bought or made, and it carries the stock's unit cost as "Prep invested". If an earlier run is still on hand, that's a weighted average of both runs.
4. Harvest. Log each flush's fresh weight, and its dry weight if you dry. A bulk block then shows its cost per fresh pound and per dry pound, or per kilogram.
5. Strains. Each strain shows a typical cost per fresh pound. That's the median across finished bulk blocks with prep cost and a harvest logged, for blocks started in the last 90 days or all time.

Hypha's figure has limits you should know before you quote from it:

• Supplies, bought blocks and prep only. The app's own note says it excludes labor, packaging and delivery. The tent, room, power and anything you don't enter as a supply, bought block or prep cost stay outside it too. Add them with the formula above.
• No lineage costs yet. Hypha doesn't yet split a jar's or spawn bag's cost across the blocks made from it, so add spawn you made yourself to the prep total.
• Lost blocks drop out. A block with no harvest has no cost per pound, so it leaves the strain's typical figure instead of raising it. Apply your own loss rate on top, as in the table above.
• Costs attach at the start. A block counts only if you start it from prepped stock in Inventory, bought or made; you can't add a prep cost to a block afterward.

Pro costs $12 a month; the free plan doesn't include cost tracking (pricing).

Other questions

How do I split one tent's costs between strains?

Split shared costs, such as the tent and power, by blocks started, or by shelf-weeks if some strains stay in longer. A strain that holds a shelf for 8 weeks uses more of the tent than one rotated out at 3. Then add each strain's own block costs and divide by that strain's own fresh pounds.

What does a dry pound cost?

For oysters, a dry pound costs roughly nine times as much as a fresh pound, before drying costs. Raw oyster mushrooms are about 89% water (USDA FoodData Central), so a fresh pound dries to roughly a tenth of a pound. Log dry weights and divide by those if you sell dried mushrooms.

What should I charge per pound?

Price from your full cost per pound, including your time, packaging and delivery. Then check it against what your own buyers pay, for each product and sales channel. The Cornell and Fungi Ally guide left price per pound out of its farm data, because several farms' sales mixed mushrooms with kits, supplies and workshops. Our guide to selling the mushrooms you grow covers what other growers charge, by channel.