Creating your own mushroom agar recipes is not difficult. It can be helpful when you're missing an ingredient and need to make agar quickly.
Understanding the basic principles will help you become skilled and confident in trying different ingredients.
Once you have your agar ready, you can safely work with it inside a Still Air Box like the one we offer at Trippy TEK. Let’s get started!

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Agar Recipes: Don’t Worry Too Much!
There are countless agar recipe options available, and you might feel tempted to search for the "perfect" one. However, as a beginner, your primary goal should be to master the agar preparation process.
Once you've perfected that, you can experiment with your own recipes. In this guide, we’ll introduce proven recipes, explain their purposes, and show you how to customize them based on your needs.
Why Are There So Many Agar Recipes?
Respected mycologists use different recipes for different purposes. For example:
Germinating spores (mushroom spores)
Cleaning contaminated cultures
Multiplying mushroom cultures
Some growers also rotate recipes to keep cultures strong, while others avoid sugary media, believing it may contribute to mycelium aging (a process called senescence ).
The science behind this isn’t fully settled, so don’t stress too much about it—focus on learning the basics.
There are many recipes because, as we’ll see later, different ingredients can do the jobs of a solvent, energy source, and supplements.
For example, water works as the solvent, while ingredients like malt extract or potato flakes provide energy. Supplements like yeast add extra nutrients to help the mycelium grow strong.
This makes it easy for growers to mix and match ingredients to create recipes for specific needs.
Experiment with Your Own Agar Mushroom Recipes
Ingredient 1: Water
Water serves as the solvent in the agar recipe, and there aren't many ways to experiment with it. However, there are a few options:
Distilled Water: This is the recommended option, but it may not always be available. For home mycologists, it may be unnecessary, so don't worry too much if you don’t have it.
Tap Water: Water from your sink works fine for most recipes. Even with minerals in the water, your agar solution will still work well.
Grain Water: If you’ve soaked grains, you can collect the leftover water. This helps the mycelium adapt to the substrate it will eventually grow on.
Ingredient 2: Agar Agar Powder (1-2%)
To keep it simple, aim for a concentration of 2% by weight. For 500ml of solution, use 10g of agar agar powder, and for 1L of mixture, use 20g.
Typically, agar agar is used in the range of 1% to 3% by weight. Softer gels (1-1.5%) are ideal for germinating spores, while firmer gels (2-3%) are best for cloning or transferring mycelium.

What is Agar?
Origin and Function
Agar is a gel made from red seaweed. It functions like the gelatinous substance in Jello or pectin in fruit jelly: it dissolves in hot water and solidifies when it cools, trapping whatever is inside. The molecule that gives agar its gel-like consistency is called agarose.
Unlike gelatin, which mycelium can digest and turn into a goopy mess, A-A provides a solid surface that mycelium can grow on without breaking down.
This solid surface allows you to cut healthy wedges of mushroom mycelium to inoculate other substrates, like grain jars.

Types of Agar
There are different purities of agar. Higher purity agar is often used in scientific labs for applications like DNA testing. For mushroom growing, food-grade agar is sufficient, affordable, and works perfectly.
Where to Find Food-Grade Agar
Food-grade agar, often called “agar-agar,” is easy to find at Asian grocery stores or online. A popular brand is Telephone Brand, which has a rotary phone logo on the package.
However, as long as the agar is food-grade, any brand will work just fine.
Cost and Convenience
Food-grade agar is very affordable—about $2 for enough to make around 60 petri dishes. This makes it an easy and cost-effective option for mushroom cultivation.
Why Agar is Better Than Other Gels?
Agar has two major advantages over other gels like pectin (used in jelly) and gelatin (used in Jello):
Higher Gel Temperature: Agar solidifies at a higher temperature than pectin or gelatin, so it doesn’t need refrigeration to stay solid.
Resistance to Breakdown by Bacteria and Fungi: The air is full of bacteria and fungi that produce enzymes, like pectinase and gelatinase, which can break down gelatin and pectin. This would turn your gel back into a liquid, which isn’t ideal for growing mushrooms.
Agar, however, is less likely to break down because bacteria and fungi that produce the enzyme "agarase" are rare. This means agar remains solid, even when contaminants are present, providing a stable surface for growing mushrooms.
Ingredient 3: Energy Sources (1-8%)
Energy sources are the primary food for your fungi. There are many options available for providing energy, but it's important to understand the two types of carbohydrates: simple carbohydrates and complex carbohydrates . A mixture of both types is ideal, as complex carbohydrates are better for long-term health, while simple carbohydrates provide quick energy.
Simple Sugars
Concentration: Aim for 1% by weight (5g for 500ml, 10g for 1L solution). The range can vary from 0% to 2%.
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Types of Simple Sugars: These include glucose, fructose, sucrose—simple carbohydrates that fungi can easily metabolize for immediate energy.
Examples: Table sugar, honey, and syrups.
Usage: Fungi prefer these sugars for fast growth. They are commonly used in mycology recipes to promote rapid growth.
However, Paul Stamets doesn't recommend them for long-term use, as they can lead to mutations, senescence, and dieback in the culture.
Standalone Options (Simple Sugars with Both Simple and Complex Carbohydrates):
These ingredients naturally contain a balanced mix of simple and complex carbohydrates, so they don’t require mixing with additional complex sugars:
Light Malt Extract : 2% by weight.
Cornsteep Fermentative : 2% by weight.
Barley Malt Extract : 2% by weight.
Simple Sugars That Need Mixing (With Complex Sugars):
You can mix simple sugars with complex sugars for improved results. While there's not much difference in which complex sugar pairs with a simple sugar, some pairings offer slight advantages based on nutrient needs or growth preferences.
Table Sugar (Sucrose): Pair with potato flakes, corn starch, or malt extract.
Dextrose (Glucose): Pair with potato flakes, corn starch, or malt extract.
Honey: Pair with oatmeal, wheat/rye flour, or potato flakes.
Maple Syrup: Pair with rye/wheat flour, malt extract, or cooked potatoes.
Corn Syrup: Pair with potato flakes, oat flour, or barley malt extract.
Grain Water: Pair with barley malt extract, potato flakes, or corn starch.
If Unsure or Unavailable:
Potato flakes or malt extract are versatile and widely applicable, pairing well with any simple sugar for balanced fungal growth.
Complex Sugars (Starch)
Concentration: Aim for 2% by weight (10g for 500ml, 20g for 1L solution). The range can vary from 0% to 8%.
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Types of Complex Sugars: These include starches (polysaccharides), which fungi must break down into simpler sugars before they can use them.
Examples: Potato flakes, corn starch, oat flour.
Usage: Complex sugars provide a slower, more gradual release of nutrients. They are commonly included in recipes like Potato Dextrose Agar (PDA) to provide sustained energy.
- Paul Stamets’ Insight on Complex Sugars: Stamets recommends using complex carbohydrates like starches for long-term fungal strain maintenance. Simple sugars can promote rapid growth but may lead to mutations and dieback. Starches support slower, more stable growth, reduce metabolic stress, and help preserve genetic integrity.
Standalone Options (Complex Sugars):
Certain complex carbohydrates can be used alone as a primary energy source in your agar recipe:
Potato Flakes : 2% by weight.
Cooked Potatoes : 2% by weight.
Oat Flour : 2% by weight.
Cornmeal : 2% by weight.
Need Mixing (With a Simple Sugar):
Some starches are best when paired with simple sugars to provide both immediate energy and sustained metabolism:
Corn Starch: Pair with table sugar, honey, or dextrose.
Wheat Flour: Pair with maple syrup, honey, or corn syrup.
Wood (Cellulose): Pair with barley malt extract, grain water, or light malt extract.
If Unsure or Unavailable:
Potato flakes are the most versatile and widely applicable. They pair well with simple sugars like dextrose or table sugar and are commonly used in mycology recipes.
Ingredient 4: Optional Supplements
Optional ingredients, such as nitrogen sources, oat-based or grain flours (complex carbohydrates), and end-substrate supplements, can serve specific purposes in agar recipes.
Each ingredient plays a role in enhancing fungal growth, balancing the nutrient profile, and sometimes mimicking the conditions fungi encounter in their natural substrates.
Do You Need Nutrient Additives?
Yeast Extract and Peptones:
Function: These provide nitrogen, vitamins, and other nutrients that promote growth.
Usage: Peptones are primarily used for culturing bacteria or isolating fungi in medical diagnostics, not for general mycology or gourmet purposes.
Quantity: The amounts needed are very small—only a small pinch or a fraction of a gram is required for most recipes.
Malt Extract Alone is Enough:
Function: Malt extract provides sufficient nutrients for spore germination, cleaning, and pure culture expansion.
Recommendation: Adding nitrogen-rich media, like peptones, is unnecessary for most mushroom cultivation. In fact, it can encourage contamination and may not be needed for typical recipes.
Quantity: Again, very small quantities are needed—malt extract is usually used at 2% by weight, which is equivalent to just a few grams per liter of solution.
Conclusion
Congrats! You've successfully made your own agar plates instead of buying pre-poured ones online!
Again, if you prefer a mindmap format with all the same info, please have a look here!
FAQ
How to make Agar for petri dishes?
To make agar for petri dishes, mix agar ingredients (such as agar powder, water, and nutrient sources like malt extract or potato flakes), sterilize the solution in a pressure cooker, then pour it into sterile petri dishes while still warm and liquid.
Are agar plates and petri dishes the same?
Yes, agar plates and petri dishes refer to the same thing—flat, shallow dishes used to culture mycelium or other microorganisms, typically with agar as the growth medium.
How much agar to use?
For 500ml of solution, use 10g of agar powder . For 1 liter of solution, use 20g of agar powder .
Best agar powder?
The recommended agar powder is Telephone Brand . It is available at Asian grocery stores and online, offering a good value for mushroom cultivation.
How much is agar?
Food-grade agar powder costs around $2 for enough to make about 60 petri dishes, making it a very affordable option for mushroom cultivation.
How to store agar dishes?
After pouring, wrap the agar dishes to allow for gas exchange while keeping them protected from contaminants.
Store them in the fridge or a designated storage area to maintain sterility.
For extra protection, place the dishes in their plastic sleeves, seal them, and they can be stored this way for up to 2-3 months.