This guide contains an introduction to steps and strategies for growing mushrooms at home. Mushrooms are a delicious addition to many foods such as pizza, pasta, soups, and salads. Mushrooms are actually fungi and not plants.
They do not have chlorophyll, which allows plants to manufacture their own food. Mushrooms typically feed on the decaying matter where they are growing. They absorb nutrients from the substrate that have already been broken down by bacteria, and do not have root systems like plants do, nor do they have stems and leaves. The “stem” of a typical mushroom is just a stalk, a supportive structure for the cap. The mushroom cap is similar to the fruit of plants, and not a leaf of some sort.
Mushrooms are highly prized for their distinct flavors. Enokis and shiitakes were traditionally used in Asian cooking but have already found their niche in fusion cuisine. Aside from their unique flavors, mushrooms are also rich in minerals, nutrients and antioxidants that have many health benefits.
Most often, people think that growing mushrooms is a complicated and sensitive process. In this book, find out just how easy it is to grow delicious mushrooms safely and successfully right in your home. In fact, it is possible to use a small dark closet to grow these mushrooms.
So What are Mushrooms anyway?
Mushrooms are among some of the oldest known “plants” in the world and have been used for centuries in various ways. The Ancient Egyptians believed that mushrooms were plants for immortality. There was even a decree that reserved eating them strictly for the royalty.
Other cultures across the ancient world also held rituals involving mushrooms, such as in Greece, Latin America, Mexico, China, and Russia. Ancient civilizations believed in the many “powers” of this small plant. They believed that it could give super human strength, lead one’s soul to where the gods lived and help one find things that were lost.
1 - Mushrooms are fungi
The truth is, mushrooms are not plants. They are botanically classified as fungi organisms that do not have true leaves, stems, and roots. They thrive by absorbing nutrients from decomposing plant matter such as barks and leaves.
2 - Early Mushroom Cultivation
The first formal mushroom cultivation system was in France. Accounts claim that the first mushroom grower was Louis XIV. There was a special cave in Paris that was set aside just for growing mushrooms.
English gardeners soon picked up the practice. They found that the cultivation was very easy, requiring minimal labor and tending, space and investment. Soon, mushroom growing spread across Europe.
The practice found its way to the United States in the late 19th century. Growers depended on imported spawn from England. Because of the long journey, most of the spawn ended up being of low quality by the time they arrived in the United States and were sold to growers.
3 - Basic Mushroom Growing Process
Mushrooms grow from spores, not from seeds like most plants. A single mature mushroom can send out billions of spores. These spores are collected in a sterile environment and then inoculated into grains or “seeds”, more aptly called spawn. The spawn is to mushrooms what seeds are to traditional agriculture.
Mushrooms obtain nutrients from the organic matter found in the growing media, which is called compost. The growing media is a combination of corncobs, straw, cocoa seed hulls, gypsum, cottonseed hulls and supplements that contain nitrogen. Compost preparation takes about 1 to 2 weeks before it is pasteurized and placed in the growing beds or trays. The spawn is worked into the compost and is left to grow and mature. In homes, the mushrooms are often grown in the basement, where it is dark and moist.
Lacy white filaments start to form networks all over the compost. These are the “roots” of the developing mushrooms. After a few days, the mycelium starts to emerge. This stage is called the pinning stage. Eventually, these pins develop into the mushroom caps, which are synonymous to the fruits of plants. It takes an average of 17 to 25 days for the caps to mature.
The mushrooms are harvested once the caps are mature. Depending on the variety, caps range from the size of a button (or smaller) to large saucer-sized ones. Harvesting is done over several weeks. Once everything is harvested, the entire growing area is steam sterilized to kill any residual spores, fungi or bacteria that can contaminate the next season’s planting.
Types of Mushrooms to Grow at Home
Over the years, mushrooms have become more and more incorporated into our daily diet. As people became aware of the health benefits and the deliciously unique taste of mushrooms, demand for them becomes higher. Today, there are several mushroom varieties cultivated such as white mushrooms, cremini, Portobello mushrooms, oyster, enoki, shiitake, maitake, and beech mushrooms.
1 - White Button Mushrooms
White button mushrooms are among the most popular and widely used mushroom variety. These are hardy ones, too and bear many “fruits”. White button mushrooms are used for everyday meals like meatloaf, pizza, pasta dishes, stir-fries, soups and a host of salads.
2 - Cremini Mushrooms
Cremini caps have a darker color. The texture is also slightly denser compared to white mushrooms.
3 - Portabella Mushrooms
The process of growing Portabella mushrooms is similar to growing white mushrooms. This is not actually a different mushroom variety. Rather, it is a more mature cremini. The caps are harvested 3 to 7 days later than the cremini. Harvesting them later allows the caps to grow longer and develop into bigger caps that can grow up to a diameter of 6 inches.
4 - Oyster Mushrooms
This variety needs fresh air and more humidity compared to white mushrooms. Oyster mushrooms grow best in wood and in agricultural waste products, which include chopped cereal straws, hardwood chips, and corncobs.
Spawn of oyster mushrooms are mixed into the growing medium then packed into plastic bags shaped into long tubes. Holes are made in the bag so that the mycelium will be able to breathe. The bags are hung or set on racks. It takes an average of 14 days before the mushrooms grow out of the holes and are ready for harvest.
Oyster mushrooms have subtle flavors with soft and thick textures. You can eat them either raw or cooked. This variety is often included in Oriental cooking.
5 - Shiitake Mushrooms
Shiitakes were originally grown on natural oak logs. It usually takes around 2 to 4 years for the mycelium to settle and grow on the wood and produce the caps. Harvesting is on a seasonal basis, in the spring and the fall for six years. This long time span is the reason shiitake mushrooms are very expensive.
Today, newer methods have been developed to make shiitake mushroom cultivation faster and easier. Man-made Oak logs are made by using poly bags that are filled with oak sawdust and then sterilized. Inoculation is done and then placed in growing rooms. The mushrooms grow on these man-made oak logs and are harvested in 7 weeks. The entire process only takes four months compared to the traditional six years.
6 - Enoki Mushrooms
The modern process for growing enoki mushroom utilizes automated systems that fill several plastic bottles with substrate. The substrate is usually a combination of ground corncob pellets, soybean meal, and wheat bran. Once filled, the plastic bottles are subjected to sterilization and inoculation. Once the mycelium fully colonizes the substrate, plastic collars are placed at the mouth of the bottle. These collars will act as guides so that the mushrooms grow upward and form straight “stems”.
Enoki mushrooms grow in colder environments (about 45 degrees), unlike most other mushrooms (about 60 degrees). Harvest is in about 90 days. It is crucial to detach the plastic collars before plucking the enokis out of the mouth of the bottle.
7 - Beech Mushrooms
Growing this variety is similar to that of enoki. However, it requires higher temperatures of around 60-64 degrees. You can harvest mature crops after 100 days. The substrate for both enokis and beech mushrooms can be recycled because only one set of fruiting bodies is produced. In most other mushroom varieties, the substrate is not useful for other farming purposes because the fruiting bodies left in the substrate can interfere with the next batch of mushrooms.
How to Prepare for Growing Mushrooms at Home
To start mushroom growing at home, prepare the following materials.
Pitchfork – This will be useful in turning and mixing the compost. The best type to use is one with five or six prongs.
Trays – Wooden boxes or trays are useful during the inoculation of the mushrooms into the compost. In some varieties, the mushrooms will be grown in these trays. They should be deep, at around 10-12 inches.
Spawn - This refers to the pure culture of the mushroom variety intended to be grown. This contains the mycelia or the root-like and slender filaments that were prepared in a special media. The spawn will continue its growth once placed under suitable environmental conditions.
A moist spawn is an actively growing mushroom mycelia. After releasing the spawn from the laboratory, it is used immediately. Growth proceeds quickly because the spawn is already in its growing stage and follows an uninterrupted process from the laboratory to the growing media. Commercial growers use this type most often. However, moist spawn is very fragile and susceptible to damage. In addition, this kind of spawn needs a continuous nutrient supply throughout the growing and fruiting period.
Dry brick spawn or dry flake spawn is most recommended for home gardeners. This is because of its hardiness and its higher chances of survival into the fruiting period. In addition, there is a strong possibility that the compost is not yet ready once the spawn arrives. Dry brick or dry flake spawn are dry and dormant mycelia. The growth is temporarily halted, which will resume once it is planted.
Watering can – It is important to place a sprayer (pump type) in the watering can to emit a fine mist during the watering process. This will provide the adequate moisture needed for mushroom growth, not too much and not too little.
Sieve – This is useful in straining the casing soil. The mesh should be 3/16 of an inch, the sieve 3 inches deep and 15 inches by 15 inches.
Substrates – The substrate is where the spawn will be inoculated in. Different mushroom varieties require different substrates. Make sure the appropriate one is used.
Mushroom Growing Kits - These are most recommended for beginners in the mushroom growing industry. These kits include grow bags that are already pre-mixed with substrate. The spawn is inoculated through the holes in the bags. The mycelia will grow right off the bag and during harvest, the top of the bags are cut off.
There are 2 phases involved in preparing the compost.
Phase I is the preparation of compost. This is what the growing mushrooms will depend on for nourishment. There are basically 2 types of materials used as compost material. The least expensive and most popular material is horse manure bedded with wheat straw.
The other type is synthetic compost, which technically describes all other mushroom compost that does not contain horse manure. Nitrogen supplements are added to both types of compost material to augment the nutrient levels. Gypsum is also added as a conditioning agent.
In Phase I, the compost is made outdoors in an enclosed area or a simple structure with a roof overhead. Pile the materials and mix them together. The next step is to spray water all over it to wet all of the ingredients. Mix them again and arrange them in a rectangular pile, with the center loose, and the sides packed tight. Make sure to mix the pile and spray it with water regularly. Spread nitrogen and gypsum over the top layer of the compost and then turn thoroughly using a compost turner.
Leave the compost to allow aerobic fermentation. Microorganisms grow and reproduce within the compost, breaking the organic material into easily absorbed nutrients. This process produces byproducts such as carbon dioxide, ammonia, and heat. On occasion, supplements and water are added to keep the fermentation process going. In addition, turning is necessary to introduce oxygen into the compost to fuel fermentation.
Gypsum is added in order to reduce the formation of grease, which can block off the entry of air between the composting materials. The general recommendation is to add 40 pounds of gypsum for every ton of dry composting ingredient.
Nitrogen supplements are added to the compost pile. Common sources include seed meals (from cotton, peanuts, and soybeans), brewer’s grain, and chicken manure. These aim to increase the nitrogen content of the compost to 1.5% for horse manure and 1.7% for synthetic compost. The computation depends on the dry weight of the compost material. Nitrogen is crucial for good mushroom growth. For synthetic composts, add urea or ammonium nitrate to improve the growth and reproduction of nitrogen-fixing bacteria. These bacteria are the ones responsible for the conversion of organic material into nitrogen that will be absorbed by the mushrooms.
The compost pile should initially be 5-6 feet wide and 5-6 feet high. This Length is necessary to accommodate the compost material adequately. Keep the sides of the compost pile firm and dense, the center should remain loose. Materials like hay and straw soften during the entire composting process.
The pile turns less rigid, and compaction occurs. When compost materials are compact, air cannot circulate well within the pile, and that will support the development of an anaerobic environment and stop the fermentation process. To prevent this, turn every 2 days, when the pile has reached internal temperatures of 145 to 170 degrees Fahrenheit. Heat is also a crucial factor in composting, so avoid too much turning.
The compost is ready to enter Phase II if the following are noticeable:
This phase is where the compost is finished. It achieves two main purposes: pasteurization and removal of ammonia. Pasteurization is a process that kills nematodes (worms), insects, pest fungi and other undesirable microorganisms in the compost. Too much ammonia in the compost can kill mushroom spawn, so removing them is necessary.
Growing the Mushrooms
Once the compost is ready, it is time to grow the mushrooms.
1 - Preparing the Environment
Mushrooms grow well in dark and chilly areas. In the wild, you can often find them growing healthy and abundant under the damp shade, underneath rotting trees and foliage, away from direct sunlight and air currents. Growing mushrooms at home means recreating the environmental conditions of their natural habitat.
Temperatures should be cool. Generally, mushrooms grow well at 55 to 60 degrees Fahrenheit. Some, like the enoki, will require cooler temperatures.
The growing place should be dark. Basements that are not heated are ideal. A dark closet in the house or a shed are also good places to grow mushrooms. If the house becomes hot during summer, then do your mushroom growing during the colder winter months instead. This way, you can avoid overheating the growing mushrooms.
A high moisture level in the air is also best for growth. A humidifier is recommended for dry regions to improve humidity levels and support better mushroom growth.
2 - Spawning: Adding the Spawn
Make sure that the compost is no longer emitting heavy ammonia smells. Ammonia can kill the mycelia.
Place the compost in the growing trays. For every 12-15 square feet (ft2) of compost in the trays, add 1 quart of dry flake or dry brick spawn. For dry brick spawn, insert a 1 ½-inch square of spawn for every 6 inches, at 1-2 inches deep. Add enough compost to provide cover for the spawn and press down to firm down the compost.
For dry flake spawn, allow the compost to mature in the stack. Wait until all the odor of ammonia disappears. Make one extra compost turning. Sprinkle the dry flake mushroom spawn over the compost and then turn the entire stack. Spread the spawn-compost mixture into the growing trays. Set the mixture aside, loosely heaped in the trays, for 24 hours. The boxes or trays are heaped a little higher so that by the time these are pressed down, the compost-spawn mixture will be 1 ½ inches to 2 inches below the top.
After the spawn is added, the mycelia will colonize the compost. This process will take about 2 to 3 weeks. The growing trays are ready for the next step once there are networks of cotton-like mycelia that cover the surface of the compost. Keep the compost constantly moist by spraying a fine mist of water.
Do not allow the compost to dry out because the mycelia will die. If the compost becomes dry, re-moisten. Any residual viable mycelia will then continue to grow, but the yield will be much lower than expected.
3 - Casing
Casing is a step in the mushroom growing process where another layer of material is placed over the growing mycelia network. The entire mushroom will only emerge if casing is done. This layer provides an area for mycelia aggregation, which will later produce the caps. Casing material placed should be at 1 to 1 ½ inches deep.
Several materials can be used as casing. Soil is good, but it depends on the type. It should not be clay-like and heavy or very sandy. The soil used for casing should be prepared first by passing it through a sieve. Sift the soil through a 3/16-inch mesh to remove pebbles and clumped soil.
Mix in the peat just before adding the casing. Add 1/3 of peat by volume. Peat prevents compaction that can smother the mycelia. It also provides additional nutrients. If peat is not added, casing material can turn crusty after a few watering sessions. The tiny pins of the mycelia will have a difficult time breaking through the crust.
Use horticultural peat instead of bedding peat because it has less acidity. Some growers make sure that the casing has more alkaline by adding 1 cup of lime for each bucket of peat added to the casing.
4 - Checking Moisture Content
Moisture content is also crucial within the casing layer. This controls the fructification and promotes the emergence of the pins. Avoid adding water directly into the casing because this may injure the pinheads. To add moisture to the casing safely, place a few sheets of newspaper over it.
Add enough water to the newspaper layer to keep it moist. Add water at least twice a day. The newspaper layer will also protect the casing layer from being disturbed. Pinheads will not continue to grow if the casing is upset in any way.
The pinhead will grow through the casing layer and colonize it as soon as this layer is applied. It is crucial to keep the moisture in this layer. Remove the layer of newspaper after 10 days. This will allow the pinheads to fully break out. Exercise care and caution. Keep the casing layer well moistened, but still avoid overwatering. Water flowing through the casing layer will kill the mycelia. If too dry, the pins will not grow robust.
Once the newspaper layer is removed, water every other day. Apply only a light fine mist then add another light spraying after 1 hour. Gently and carefully, stick one finger into the casing layer where there is the least amount of mycelia to check if the layer gets enough moisture all the way through.
5 - Pinheads
Growth proceeds nicely when pinheads start to appear all over the growing beds in about 12 days after the addition of the casing. In 6-8 days, these pins will mature and develop into fully formed mushrooms.
Blooms and flushes will appear every 10-14 days for the next 60 to 120 days. This depends on the temperatures where the mushrooms are grown. This also makes the harvest season last for weeks. In between mushroom growth flushes, maintain high moisture content through regular fine misting. However, once the pinheads appear, avoid adding water because this will cause brown spots on the caps.
6 - Picking
Harvesting mainly depends on the preference or the purpose of the caps. Some people prefer small caps while others prefer fully matured ones. However, pick the mushrooms before the veils start breaking off the caps. However, again, this depends on preference. Some prefer to pick mushrooms after the veil breaks and the caps develop into their maximum diameters.
When picking, pick up to the base of the stem embedded into the casing. Leaving this portion will provide a habitat for microbial growth that can significantly interfere with subsequent mushroom growth. Use a paring knife to remove any stubs that remain embedded in the casing.
Alternative Growing Methods
Growing mushrooms at home will be much easier using the terrarium or the log method. For some, preparing the compost and the growing trays or boxes is too complicated. Follow any of these methods to make growing mushrooms at home easier and even more fun.
1 - Terrarium Method
Get a plastic terrarium or a Styrofoam cooler that has a lid. Old grow trays from previous agricultural projects can also be used. You can also make growing trays out of old boxes or wood. The trays should be about 6 inches deep. Cover these with several layers of wet newspaper. A growing chamber with a lid is ideal, but a dark basement will do the job quite nicely, too. If the temperature of the growing area needs to be regulated, use plastic storage bins or old fish tanks, which are deeper.
Get the appropriate growing medium or substrate for the chosen mushroom variety. There are pre-mixed beds that you can purchase. These contain diverse materials such as manure, vermiculite, sawdust, and rye meal. All of these contain a basic mixture of wood chips and compost. Fill the container with the medium.
Fruiting substrates are also available. This is a mixture of 50% potting soil and sand, and the other 50% composed of rice hulls, soybean meal, lime and chips of hardwood trees.
Add the mushroom spawn into the substrate. Plant it about 2 inches deep and several inches apart. Alternatively, just sprinkle the spawn all over the growing bed or chamber (terrarium, plastic container, etc.) and cover with compost or substrate.
Maintain the temperature of the growing substrate at 21 degrees Celsius or 70 degrees Fahrenheit. Heated rooms or areas that receive direct sunlight are ideal places. Just make sure that the terrarium itself is away from direct heat or sunlight.
In about 3 weeks, the roots or mycelia will start to spread all over the growing medium. Once thin, white networks of mycelia appear, transfer the growing chamber into the basement, dark room or closet. Reduce the growing temperature to 16 degrees Celsius or 60 degrees Fahrenheit. Place a 1-inch thick cover of regular potting soil over the mycelia (casing).
Keep the soil slightly damp all throughout the growing period. Use a spray bottle with a fine mister at the end. Covering the growing chamber with a damp cloth also helps keep the soil and the growing mushrooms damp. Daily spraying is necessary if the mushrooms are in a heated room. Maintain the dampness for 3 to 4 weeks.
Check the mushrooms regularly. If the pinheads start to appear white in color, growth is proceeding well. If the pins appear as tiny black dots, this is a sign that the mushrooms are turning into bad, inedible ones. Start the process over if the mushrooms appear slimy or over-saturated.
Again, harvesting depends on preference. Generally, growers start picking the mushrooms when the veil (thin membrane) that connects the cap to its step has lifted or separated.
When picking the mushrooms, avoid pulling them out. This will knock nearby mushrooms off and may affect those that are still maturing.
To pick the mushroom properly, hold it firmly by the base and twist until the base snaps off. Or, use a small knife such as a paring knife to cut off the mushroom at the base.
Once mushrooms are ready for harvest, remove them right away from the growing chamber. This way, flush will continue to spread, and more mushrooms will bloom over the next few weeks. This will assure a good harvest after all of your hard work.
2 - Log Method
You can also grow certain mushrooms on logs, such as the oyster and shiitake varieties. Oak logs that are already pre-inoculated can be purchased from spawn suppliers. These logs already have mushrooms planted, and all that you need is to place them in suitable growing conditions. Or, you can prepare the logs at home if there is access to freshly cut maple or oak logs. To inoculate the logs, follow these steps:
- 1Get the spawn of the chosen mushroom variety.
- 2Get some maple or oak logs. Make sure these are freshly cut. Inoculate these quickly before any competing organisms get a chance to establish themselves in the logs.
- 3In each log, cut out 3- to 8-inch holes along the logs, in a diamond-pattern.
- 4Fill these holes with the spawn.
- 5Once filled, plug the holes with wax to protect the spawn from bacteria.
After inoculation, place the logs under shade. Keep them away from the sun and wind. Fruiting blankets can be purchased to cover the logs. Or, place the logs somewhere where there is a good shade cover.
As with other growing methods, keep the logs moist. Rinse the logs with a hose regularly until pinheads start to appear. Stop spraying once the mushrooms emerge to prevent damage.
Once the veil on the cap has lifted from the base, it is time to harvest. Cut off the mushrooms at the base using a small paring knife, or twist them off.
I hope this guide was a good introduction to learning how to grow mushrooms at home.
The next step is to start looking for the ideal place to set up the mushrooms. Prepare the materials and start choosing what mushroom variety you would like to plant.
Soon, you will be harvesting a good amount of delectable mushrooms, which you and your family can enjoy. You can also give some to neighbors and friends or sell them at the local grocers. If done right, you will be harvesting tons of mushrooms from just a small space.