From the farm & the lab
Growing notes, Hypha development updates and behind-the-scenes stories, written by the people building Demeter Mycolabs.
Is it safe to grow mushrooms indoors? Spores, mold and allergies, explained
Growing mushrooms indoors has two real risks: spores, which have caused lung allergies in commercial growers, and damp, which can feed mold in your house. Here's what the research says, how to cut both, and who should talk to a doctor first.
Derick9 min read
How do you prevent mushroom contamination? Clean technique from agar to block
Prevent mushroom contamination by keeping spores and bacteria away where they do the most harm: culture work in still air, fully sterilized grain, cool and spaced-out bags, and a clean fruiting space. This guide goes step by step from agar to block, then shows how to tell whether a change helped.
Derick9 min read
Why are my oyster mushrooms yellow, brown, dry or tiny? Oyster mushroom problems, by photo
Dry yellow or brown oyster caps usually mean the mushrooms are drying out, while some brown or gray on blue and pink oysters is normal. This guide also covers cracked, small and wavy caps, wet yellow or brown spots and when to give up on a block.
Derick9 min read
What's a good biological efficiency? Mushroom BE by species, and why the numbers disagree
Biological efficiency (BE) is fresh mushroom weight divided by dry substrate weight. Published BE is often 100% or more for oysters, about 45–145% for shiitake, 40–70% for king oyster and chestnut, and under 50% for maitake, but studies measure it differently. Here's BE by species, why figures disagree, and how to measure your own.
Derick8 min read
How to label mushroom grow bags, jars and agar plates
Label every mushroom plate, jar and bag the day you inoculate it, with at least the species, the date and a code that names its parent. Here's what to write, which tape survives the pressure cooker, why plates get labelled on the bottom, and how to print QR labels.
Derick5 min read
Can you grow mushrooms from store-bought mushrooms? Which ones clone, and how
Yes, for some: fresh oyster, king oyster, lion's mane and shiitake can be cloned from a grocery pack onto agar, and oyster stems can start spawn on cardboard. Button, portobello, beech and maitake are hard at home, and enoki needs cold. Here's how to clone, why clones fail, and the legal catch.
Derick9 min read
Dev log: what our Hypha Aeris air sensor caught as the caps opened
We wanted Hypha Aeris to spot mushrooms dropping spores. Then we realised our timelapses had been collecting the data for months. Here's what its PM2.5 sensor saw as the caps opened, and how close we are to a harvest alert.
Sharon21 min read
How to sell the mushrooms you grow: farmers markets, restaurants and the rules
In many states you can sell fresh, whole cultivated mushrooms you grow with little or no licensing at small scale; drying, slicing or bigger sales add rules. Here's what markets and restaurants expect, what growers charge, and which records to keep.
Derick9 min read
When to harvest mushrooms: too early, just right and too late, from our timelapses
Oyster mushrooms can go from perfect to past it in a few hours. Here's what too early, just right and too late look like, in frames from our own timelapses. Plus shiitake, king trumpet, lion's mane and maitake.
Sharon13 min read
Stages of mushroom growth, with pictures: what each stage looks like and what to do next
Gourmet mushrooms grow through stages you can see in a jar or grow bag, from culture to pins and mushrooms; here's each in pictures and what to do next. It also covers how to tell each stage is done, the flushes after harvest and where a kit starts.
Derick9 min read
How to get a second flush of mushrooms: rest, soak and flush counts by species
To get a second flush of mushrooms, rest the block one to two weeks in fruiting conditions. Soak oyster and lion's mane only if they dry out, and rest shiitake longer, then soak it after every harvest. This guide gives rest, soak and flush counts by species, explains why later flushes shrink, and shows when a block is done.
Derick9 min read
Why is my lion's mane turning pink, yellow or brown? Lion's mane problems, by photo
Pink on young lion's mane usually fades, yellow usually means it got too dry, too wet or old, and wet-looking brown or orange patches mean it's rotting. This guide also covers coral shapes, lumps and fruit growing inside the bag.
Derick9 min read
Why did my mushroom colonization stall? How to tell slow from stuck in grain and blocks
Colonization that looks stalled is often just slow: a cold room, a slow species or faint mycelium. A real stall usually traces to wet or dry substrate, too little spawn, blocked air or a tired culture, and this guide shows how to tell which and when to give up.
Derick9 min read
Best mushroom growing kit for beginners: how to pick one and grow your first flush
The best mushroom growing kit for beginners is a ready-to-fruit oyster kit, which usually gives a first harvest within about two weeks. This guide compares kit types, matches a species to your room, and walks you through the first two weeks stage by stage, with sourced yields and fixes.
Derick9 min read
Why aren't my mushrooms pinning? How to diagnose no pins, stalled pins and side pins
Mushrooms that won't pin are usually too dry, short of fresh air, at the wrong temperature or not ready yet, and this guide shows how to tell which. It covers stalled pins, side pins, mushrooms inside the bag and the North Spore kit reset.
Derick9 min read
How to store fresh mushrooms, and how long each kind lasts
Store fresh mushrooms unwashed in a paper bag in the fridge: most last about a week, pink oysters a day or two. Here's what the research says for each species, and why pinks are different.
Sharon15 min read
Mold or mycelium? How to identify mushroom contamination at every stage
How to identify mushroom contamination at each stage, from agar and grain to bulk and fruiting blocks: green mold, cobweb, bacteria and other molds. The guide also covers the look-alikes that aren't contamination, when to toss or salvage, and how to clean up safely.
Derick9 min read
How to build a mushroom grow room: specs and budget tiers
A mushroom grow room holds blocks at 85–95% humidity, with fresh air, a steady temperature and some light, in tents inside a dry room or in one sealed room. This guide helps you choose, then covers the space, walls and floor, fresh air, humidity, heating and cooling, light, safe wiring, and three budgets.
Derick38 min read
How to calculate mushroom cost per pound: tent, room and microfarm
Mushroom cost per pound is what you spent on blocks, running costs, equipment and time, divided by the fresh pounds you harvested. This guide prices a block three ways, shows how yield and lost blocks move the number, and adds room and microfarm costs from published farm studies and grant reports.
Derick12 min read
Mushroom CO2 and fresh air: targets by species and stage
Fruiting mushrooms need CO2 under about 1,000 ppm, and oysters less; measure it with an NDIR sensor rated to 95% RH, mounted out of the mist. Colonizing blocks tolerate 10,000–20,000 ppm. The guide gives sourced targets by species and stage, fresh-air setups from monotubs to rooms, and where to put the sensor.
Derick13 min read
Mushroom grow log: what to record and how to track lineage
A mushroom grow log records each culture's parent and generation, each block's substrate and spawn, and each flush's date and weight. This guide gives the fields, a lineage code, the BE and contamination formulas, a free template, and how the apps compare.
Derick16 min read
Mushroom grow timeline: inoculation to harvest, by species
From inoculating grain to first harvest, pink oyster takes about 4–7 weeks, blue oyster and lion's mane 5–9, and shiitake on sawdust 9–17. The guide breaks each grow into stages for six gourmet mushrooms and shows how to plan a steady weekly harvest backward from a target.
Derick11 min read
Martha tent sizing and setup checklist
How big a Martha tent you need, what it holds, and how to set up the humidifier, fan, controller and sensor so it fruits well. The guide also covers cleaning, costs, and when to move up to a second tent or a grow room.
Derick31 min read
Dev log: meet Rhizo, the assistant that reads your farm
We're building Rhizo, an AI assistant inside Hypha that answers from your own farm's records. It's in testing with our team and isn't available yet. Here's what it can already do, what it won't do, and some of the code behind it.
Derick8 min read
Dev log: teaching Hypha to run your fans (and what happens when it can't)
We're building climate control into Hypha: Hypha Aeris (closed beta, not for sale yet) switches a zone's humidifier, fans and heater through smart plugs. It's in testing on our bench and isn't available yet. Here's how it works, what it does when something goes wrong, and how we tried very hard to break it.
Kaylee10 min read
Liquid culture syringes: buy, expand or make your own
When to buy a liquid culture syringe and when to make your own liquid culture, and what each route costs. The guide also covers how to make and test a jar at home and inoculate grain from it.
Derick18 min read
Liquid culture mycelium: a buyer's guide for growers
What to check before buying liquid culture, when a syringe beats a jar, and how to store, test and log each culture on arrival.
Derick16 min read
Pink oyster grain spawn: readiness, rates and expansion
How to tell when pink oyster grain spawn is ready, and what healthy and contaminated bags look and smell like. The guide also covers spawn rates, grain-to-grain expansion, and how pink compares with blue oyster.
Derick12 min read
Fruiting chamber humidifier sizing and setup guide
How to size a humidifier for a monotub, shotgun chamber, martha tent or grow tent, and where to place the humidifier. The guide also covers holding 90%+ RH without soaking your substrate, and keeping the reservoir from becoming a contamination source.
Derick11 min read
Fruiting chamber temperature: target ranges by species
Target fruiting temperatures for blue and pink oysters and lion's mane, and what goes wrong outside each range. Plus cheap ways to keep your chamber in range.
Derick9 min read
Dev log: teaching Hypha to see
We're building a photo check into Hypha that can flag contamination and tell when a flush is ready. Here's where it stands: 90,000 public photos, two human labelers, one frozen vision model, honest numbers, and what has to happen before it ships.
Derick10 min read