A practical guide to growing mushrooms in IndiaA joint educational initiative by MushroomWale & DMR Solan ↗
MushroomFarming.in

A joint educational initiative by

MushroomWale.com
ICAR–Directorate of Mushroom Research, Solan logoICAR–DMRSolan
Topics

MushroomFarming / technical parameter

Phase II Compost Tunnels

Understand the insulated envelope, plenum, air floor, return path, fan, dampers, sensors, door and drainage.

Practical explanation + detailed referenceSources & review ↓
Polythene compost bags topped with dark casing soil and emerging button-mushroom pinheads in a dim cropping room, Tamil Nadu (uploader is a TNAU student; Tamil caption 'mushroom cultivation method').
Real cultivation photograph. Read its source for location and context; it is not a universal operating specification.Rahumath nisha · CC BY-SA 4.0View full photograph ↗
On this pageChoose a section, or keep reading below

Read this in the full guide: Understand and document a compost batch →

Understand the topic

Start with the explanation.

Operate air paths by process objective and verify the compost response across the load.

Part 01

Simple explanation

A tunnel recirculates and conditions air through a loaded compost mass.

Conceptual compost heap cutaway showing straw structure and internal spaces.
AI teaching illustrationStructure and air

The heap has structure, depth and internal variation. One central reading does not describe every part of the material.

Conceptual explanation—not a real farm photograph, diagnostic finding or construction specification.
Part 02

What is happening

The tunnel couples biological heat and gas exchange with forced convection, pressure distribution and controlled fresh-air exchange.

Part 03

Operator explanation

Operate air paths by process objective and verify the compost response across the load.

Part 04

What to look for

Observation should describe stage, location, pattern and change history before interpretation.

  • Door seal
  • floor cleanliness
  • plenum drainage
  • damper motion
  • air bypass
  • sensor map
Part 05

What to measure

Measurement must retain method, unit, location, timing, calibration and sample identity.

  • Airflow at pressure
  • plenum pressure
  • air and compost temperatures
  • fan state
  • damper state
Part 06

Equipment and process boundary

Equipment is useful only when its role in the biological process is explicit.

  • Insulated enclosure
  • plenum
  • distribution floor
  • fan
  • dampers
  • controller
  • drainage
Part 07

Variables that interact

Envelope, floor, plenum, fan, mixing section, fresh air, return air, exhaust, heating or steam where applicable, sensors and controls form one circuit.

Part 08

What can go wrong

A symptom may have several mechanisms. Verify the cause before changing the process.

  • One universal tunnel layout
  • blocked floor
  • poor plenum access
  • incorrect return path
  • fan selected by motor power
Part 09

What changes at commercial scale

Scaling changes geometry, repeatability, instrumentation, material flow and failure consequence.

  • Small bulk chambers may use different air architecture
  • Commercial tunnels need structural, mechanical, electrical and process commissioning
Part 10

What the evidence can tell you

Mapped evidence: Farm Design for White Button Mushroom Cultivation; Straightening Out Fan Curves; Improving Fan System Performance: A Sourcebook for Industry. Foundational, current operational, research and engineering sources retain their different roles.

Illustration of an operator recording a compost probe reading beside material samples.
AI teaching illustrationRelease with evidence

The batch record brings measurements and observations together. The calendar alone cannot prove compost is ready for spawning.

Conceptual explanation—not a real farm photograph, diagnostic finding or construction specification.

Go deeper

Technical reference, records and tools.

Detailed crop-stage information, parameters, diagrams and specialist tools are kept together below. This material retains its source conditions and review limits.

Open the complete technical reference

Compost system · engineering guide

Phase II Compost Tunnels

Understand the insulated envelope, plenum, air floor, return path, fan, dampers, sensors, door and drainage.

Crop context
Agaricus bisporus
Publication
Public editorial page
External review
Not yet recorded · needed from Button Mushroom compost technical reviewer
Evidence records
3
Polythene compost bags topped with dark casing soil and emerging button-mushroom pinheads in a dim cropping room, Tamil Nadu (uploader is a TNAU student; Tamil caption 'mushroom cultivation method').
Button mushroom compost bags with pinheads in a dark grow room. Photo: Rahumath nisha, CC BY-SA 4.0. Source

Compost temperature from day 0 to spawning

Long-method heap 65 to 70 °C with turnings, then pasteurisation at 58 to 59 °C for 4 to 6 hours, conditioning at 45 to 52 °C, cooling to 25 to 30 °C for spawning. Source: ICAR-DMR manual 2011.

30°40°50°60°70°80°turnturnturnPhase I: outdoor heap, 65 to 70 °CPhase II: 58 °C, then 45 to 52 °Cspawn at 25 to 30 °Cday 0day 22
Phase I heapPhase II tunnelPasteurisation band
Picture → explanation → field task

Keep clean and suspect work separate

AI-generated educational illustrations. Not actual farm photographs, diagnostic evidence or construction specifications.

Generated illustration of raw straw separated from closed cultivation bags on a different bench.
02

Protect prepared material

Raw inputs and protected prepared material are separated. Treatment does not protect a substrate indefinitely. Handling afterwards can introduce contamination.

Try this on your farm

Keep work areas, tools and movement routes separated. Label batches so a later problem can be traced to its preparation history.

Generated illustration of a covered waste tub leaving a separate area away from covered harvest crates.
04

Plan the spent-material route

Used material and saleable harvest follow different handling paths. A disposal route can undo clean-work separation if it crosses incoming materials or harvest handling.

Try this on your farm

Map the exit route and cleaning responsibility. Check the actual workflow during a busy room turnaround, not only on a drawing.

Quick orientation

Operate air paths by process objective and verify the compost response across the load.

01

Simple explanation

A tunnel recirculates and conditions air through a loaded compost mass.

02

What is happening

The tunnel couples biological heat and gas exchange with forced convection, pressure distribution and controlled fresh-air exchange.

03

Operator explanation

Operate air paths by process objective and verify the compost response across the load.

04

What to observe

Observation should describe stage, location, pattern and change history before interpretation.

  • Door seal
  • floor cleanliness
  • plenum drainage
  • damper motion
  • air bypass
  • sensor map

05

What to measure

Measurement must retain method, unit, location, timing, calibration and sample identity.

  • Airflow at pressure
  • plenum pressure
  • air and compost temperatures
  • fan state
  • damper state

06

Equipment and process boundary

Equipment is useful only when its role in the biological process is explicit.

  • Insulated enclosure
  • plenum
  • distribution floor
  • fan
  • dampers
  • controller
  • drainage

07

Variables that interact

Envelope, floor, plenum, fan, mixing section, fresh air, return air, exhaust, heating or steam where applicable, sensors and controls form one circuit.

08

What can go wrong

A symptom may have several mechanisms. Verify the cause before changing the process.

  • One universal tunnel layout
  • blocked floor
  • poor plenum access
  • incorrect return path
  • fan selected by motor power

09

What changes at commercial scale

Scaling changes geometry, repeatability, instrumentation, material flow and failure consequence.

  • Small bulk chambers may use different air architecture
  • Commercial tunnels need structural, mechanical, electrical and process commissioning

10

Evidence boundary

Mapped evidence: Farm Design for White Button Mushroom Cultivation; Straightening Out Fan Curves; Improving Fan System Performance: A Sourcebook for Industry. Foundational, current operational, research and engineering sources retain their different roles.

Progressive depth

Move from field observation to mechanism, engineering and evidence without losing the original question.

PracticalWhat the operator notices
  • A tunnel recirculates and conditions air through a loaded compost mass.
  • Door seal
  • floor cleanliness
  • plenum drainage
TechnicalHow process variables interact
  • Envelope, floor, plenum, fan, mixing section, fresh air, return air, exhaust, heating or steam where applicable, sensors and controls form one circuit.
  • Airflow at pressure
  • plenum pressure
  • air and compost temperatures
EngineeringHow the physical system serves the process
  • Insulated enclosure
  • plenum
  • distribution floor
  • Small bulk chambers may use different air architecture
  • Commercial tunnels need structural, mechanical, electrical and process commissioning
ResearchWhich evidence records govern this page
  • COMPOST-SRC-DMR-FARM-DESIGN
  • COMPOST-SRC-AMCA-FAN-CURVES
  • COMPOST-SRC-DOE-FANS

The numbers for this step, with their source.

Process values are published from ICAR-DMR guidance with the stage and measuring point they apply to. A parameter still marked pending has no published Indian value yet.

Biological and process parameters

COMPOST.PHYSICS.BULK_DENSITYpending technical verification

Contextual bulk density

Technical value pending verification
Stage
Loading and capacity planning
Measurement context
Representative material at stated compaction and moisture
Conditions
Process stage; moisture; compaction; particle structure
COMPOST.PHASE2.COMPOST_TEMPERATUREsource contextual

Phase II compost temperature envelope

45 to 59 °C
Stage
Phase II
Measurement context
Mapped points through the compost mass
Conditions
Conditioning at 45 to 52 °C before and after pasteurisation; Pasteurisation at 58 to 59 °C for 4 to 6 hours, never above 60 °C; Rise about 1 °C per hour, cool about 1.5 °C per hour

Engineering design metrics

COMPOST.TUNNEL.USABLE_VOLUMEpending technical verification

Usable compost volume

Project value pending verification
Component
Phase II tunnel
Design context
Declared internal loading envelope
Method
Project-specific engineering calculation required
COMPOST.PLENUM.PRESSUREpending technical verification

Plenum pressure

Project value pending verification
Component
Phase II plenum
Design context
Measured under the loaded floor
Method
Project-specific engineering calculation required
COMPOST.FAN.DUTY_POINTpending technical verification

Operating duty point

Project value pending verification
Component
Fan or blower
Design context
Intersection of verified fan and system curves
Method
Project-specific engineering calculation required
Evidence, applicability and review3 mapped sources

Sources support mechanisms and architecture. Technical and engineering values publish only through their separate governed registries.

Tier Afoundational

Farm Design for White Button Mushroom Cultivation

Indian farm workflow, compost-unit components, tunnel and controlled-farm engineering vocabulary.

Publisher
ICAR-Directorate of Mushroom Research
Accessed
2026-08-22
Open original source
Tier Dengineering

Straightening Out Fan Curves

Fan curve, system curve, airflow, static pressure, operating point and efficiency concepts.

Publisher
Air Movement and Control Association International
Accessed
2026-08-22
Open original source
Tier Dengineering

Improving Fan System Performance: A Sourcebook for Industry

Fan-system efficiency, control, operating point and system-resistance principles.

Publisher
United States Department of Energy
Accessed
2026-08-22
Open original source

Read the evidence

Sources & review.

Editorial update: 2026-08-22. Independent technical review is not recorded for this entry.

  1. Farm Design for White Button Mushroom Cultivation ↗

    ICAR-Directorate of Mushroom Research

  2. Straightening Out Fan Curves ↗

    Air Movement and Control Association International · 2020

  3. Improving Fan System Performance: A Sourcebook for Industry ↗

    United States Department of Energy

Reading a source is not the same as applying its instructions to every farm. Confirm species, strain, crop stage, system, region and publication date. Old chemical recommendations are not current-use instructions.

See something that needs correcting? Tell us →