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How to Care for and Fruit Your Shiitake (she-TAH-kee) Mushroom Log

You're in for a treat! When you "fruit” your log (force it to produce mushrooms), you'll have an elegant addition to your favorite foods. You can try new recipes and enjoy flavor, aroma, and nutrition that far outclass ordinary white button mushrooms. Fresh shiitakes will keep for 2-3 weeks in the refrigerator. If they dry out, just soak them for 30 minutes, and they'll bounce right back. You can blanche or saute shiitakes and then freeze them, and they'll stay tasty and tender for months.

Shiitakes are high in protein, vitamins, and minerals. Fresh and dried shiitake mushrooms are used nutritionally to fight cancer, fibrocystic breast disease, high blood pressure, and viruses, and to help strengthen the immune system, improve circulation, and reduce cholesterol.

Your log is a living organism. The shiitake mycelia cells are growing constantly, replacing the wood cells with their own cells. The mycelia, which produce the mushrooms, need air, water, and light to grow. Every two months you can force-fruit your log - fool it into thinking it's the spring or fall rainy season - by soaking it for 24 hours in non-chlorinated ice water.

First the log will "pin,” meaning little white buds will break through the bark. The pins fill out, or fruit, into beautiful brown mushrooms. At first you may get only a few 'shrooms, but as the log is soaked regularly and mycelia fill the log, you'll get more production. In the second or third year, your log can be covered with mushrooms.

After the log fruits, it must rest, with regular soaking so the mycelia can grow inside and gather energy to form mushrooms again. We recommend resting the log for about two months, soaking in non-chlorinated room-temperature water every two weeks. You can fruit it earlier, but forcing too soon or too often weakens the log. Resting longer may produce larger crops.

Keep your log strong and healthy by soaking it every 2 weeks. Use only non-chlorinated water, such as filtered or bottled water, well water or rain water.

If you take good care of your log, you can enjoy growing and eating fresh shiitake mushrooms for three or four years or more, until all the wood cells have been replaced. The light, temperature, and moisture level will affect how quickly the log will fruit and how many mushrooms you'll get. Just like people, a log produces best when it's comfortable, well rested, and well fed!

Your Kit Contains: (1) A natural, organic hardwood log, fully inoculated with shiitake spawn and mature enough to fruit, (2) a registration card, (3) a recipe book, and (4) these instructions and easy-start card.

Where to Keep Your Log: Your log likes room temperature, normal or high humidity, and a room light or shade. It likes a natural, day-and-night cycle and indirect sunlight, like a house plant. The mycelia require light to grow, so you can place your log, as you would a low-light plant, anywhere in a room where it gets the benefit of light and dark. Avoid a cold garage or basement. You can put it outside in the shade in spring & fall for fruiting and bring it inside in winter & summer. You can let Nature fruit it year 'round in your garden, in the shade, with occasional watering.

Please note the mushrooms and signs of mushrooms ­ pins, cut stems, and stem holes ­ on your log. Our guarantee states that we are sending you a log that will produce mushrooms. The signs prove that this is a viable, producing log. Once it fruits, a log MUST fruit again if it has enough internal moisture, is allowed to rest, and is shocked by a sudden, dramatic drop in temperature combined with prolonged moisture.

How To Fruit Your Log

The mycelia grow inside the log and form colonies that will become shiitake mushrooms. For the mycelia to grow, you must maintain an internal moisture level of 35-60% by soaking regularly. If a log doesn't have sufficient internal moisture to fruit, it will use the fruiting water to digest cellulose and grow mycelia and won't form mushrooms. We force a log to fruit by "shocking" it -- Creating a sudden 20-degree drop in temperature combined with prolonged moisture.

Some logs may fruit on the first soaking, stimulated by the movement of shipping. Some logs will not fruit for 30 days after shipping because movement disrupts the mycelia.

  1. Start a log calendar. Mark when you’ll soak and when you’ll shock. Rotate shocking if you have more than one log.
  2. Examine your log. Handle it gently. Look for signs of fruiting such as mushrooms, stems, stem holes, and pins. Pins are buds. They're all white or white with brown tips and look like "outie" belly buttons. Mushrooms already on the log are edible if they are not dark brown on the bottom or mushy. If they are dried, you can soak them in water and use them as any other mushroom. White fuzz on the ends or bark is shiitake mycelia. It's an indication that the log is trying to fruit and will not hurt anything.
  3. Shock your log to start the fruiting. With the log in a container, pour very cold non-chlorinated water over the log until it floats. Weighting the log down is better but not necessary. Soak it for 24 hours. The colder you can keep it, the more mushrooms you’ll get. You can put the log and tray in the freezer or fridge at night for 8-12 hours (remember - the log needs light!) or set it outside for 1-3 days in winter. Freezing won't hurt it. Empty the water, stand the log upright in a saucer or in its tray if your kit came with a tray.
  4. Increase humidity, if needed : If you have low humidity, cover it with a paper or plastic bag and leave 2" of water in the tray. (If you have high humidity or see white mycelia or green mold, DO NOT USE THE BAG.) Do not leave the bag on for more than 5 days. You may mist the log during pinning if you have dry air in your house.
  5. Watch for pins: They like more moisture and may dry out, so misting will help during pinning. If pins begin to dry out, soak the log in nonchlorinated water for 30-60 minutes and the mushrooms will keep growing.

    Pinning. In 1-3 days, little white nubs will break through the bark. Remove the bag when the pins begin to look like mushrooms. If the pins start to dry out, soak again for 20-30 minutes or mist often.

    Fruiting. In 3-6 days, you will have a "flush" of fresh, clean, delicious mushrooms.
    If you don't get mushrooms, don't get discouraged. Remember that a log may not fruit after shipping. If you don't get mushrooms on your first shocking cycle, wait 3-4 weeks and shock it again. In dry or hot climates, soak overnight after two weeks. If you don't get mushrooms with the second shock, shock it every 2 weeks for 12 hours until it starts fruiting (try those 12 hrs in the fridge). If you have no mushrooms after the second round of 12 hour ice-water soaks (2 months from your original soaking) Call us: 1-800-792-0053.
  6. Harvesting. Use a knife and make a clean cut at the bottom of the stem or twist the stem out. Pulling the mushroom off can rip the bark. For stuffing, harvest when mushrooms are 1½-2O in diameter and the edge is turned under. For bigger mushrooms, wait until they flatten out and are 2-4 inches or more in diameter. They're just as tasty and tender as the smaller ones. Little brown spots on the gills are OK. Even if the edges turn up, the mushrooms are still good. If they dry out, soak them. DO NOT EAT A MUSHROOM IF THE BOTTOM IS DARK BROWN AND/OR MUSHY.
  7. Post-Harvest Cycle: Resting: Let your log rest (no forced fruiting) for 2 months in the tray, either standing up or lying down, away from drafts and vents.
  8. Soaking: Soak your single log or Ma & Pa logs every 2 weeks. We call this the Maintenance Soak. It feeds your log so the mycelia can grow inside. The times below are guidelines only. Too much is better than too little. Even a short soak is better than none. If you get mushrooms with every soaking or mold on the bark, cut back. DO NOT MIST except during pinning. The inside should be moist and the bark should be dry.

    Maintenance Soak
    Normal humidity: 12 hours
    Low humidity: 14-16 hours
    Arid & hot climates: 16 hours or soak 8 hours every week

    If you get only a few mushrooms, increase your soaking time by 2 hours. If you have a fruiting cycle where you get no mushrooms, the internal moisture level has fallen below 35% (An older log may take a break for several cycles. Keep the moisture level up, it will come back). You can increase the maintenance soaking time by 50%-100%. Internal moisture is the single most important factor in fruiting and insufficient moisture is the single most frequent cause of failure to fruit. Overwatering can make the log lethargic, like us after a huge meal. If you soak the log too long (3 or 4 days), let it dry out for 3-4 weeks.

    If you are going away - Soak your log for 24-36 hours in room-temperature water before you go. If you will be gone longer than 30 days, have someone soak it 24-36 hours every month. Your log may not fruit on schedule, but it will begin fruiting again as you resume your maintenance soaks.

    If you forget to soak the log - The log will go dormant if it dries out, but in most cases will not die even after two months without water. If you missed the maintenance soak, shock the log. If the log has been 8 weeks or more without water, slowly restore the moisture level by soaking it for 8-12 hours every week for four weeks, then shock it.
  9. Refruiting. You can force your log to fruit again by shocking it with the 24-hour ice-water soak.

Keep these guidelines in mind, and you'll enjoy a long, fruitful relationship with your log:

Bark: The bark is like your skin - it keeps disease out and moisture in. Handle the log gently, avoid nicks and cuts. Repair wounds with cheese wax, bees' wax, melted paraffin, or candle wax. If you live in California, you will need to wax more often because sweet gum logs lose their bark easily.
Light: Mushrooms will not grow in total darkness. They need day and night cycles and shade. Prolonged direct sunlight will kill the shiitake mycelia.

Temperature: The optimum temperature is 62-78 degrees F. The mycelia and the mushrooms will grow in hotter or cooler temperatures, but more slowly. The log will go dormant around 40 degrees F. and above 80 degrees F. Freezing won't hurt and can even provide a strong shock. Logs love 70-degree days and 50- degree nights with rain. Set them outside.

California logs: Oak logs are prohibited in California because of oak wilt disease. We send sweet gum or black gum. These logs will produce more mushrooms faster than oak logs, but they will deteriorate faster as well. They require more careful handling.

If you can't get your log to produce or if you have a question, please call us at 1-800-792-0053. Doug will return your call. He'll ask questions to determine the cause and suggest steps to get the log fruiting. Our logs are fully guaranteed for 4 months, 6 months if you return your registration card. Do not let the log dry out.

OUR GUARANTEE if you follow the instructions for four months (2-3 fruiting cycles) and are not satisfied, you may return the log to us at your expense and we will replace it with a new log or with mushrooms or mushroom products or refund your money. Gift logs will be replaced with mushrooms or mushroom products. Please be patient with your log - it's a living organism with its own growing patterns. If you get frustrated, you can put your log outside in the shade, on the ground, sprinkle it occasionally, and let Nature fruit it for you.

Questions and Answers

What is the problem if the log doesn't grow mushrooms?
In almost every case, the problem is one of the following: improper temperatures, not enough water or not enough shock (temperature difference) at fruiting time. Sometimes it’s environmental conditions, such as toxins in the air or water. Be sure the log is at room temperatures during resting. Try increasing soaking time or soak more often; in winter shock the log outside. In spring and fall you can set the log under a shade tree for more, bigger shiitake. Put your log in the refrigerator or freezer for 8-12 hours during shocking. A brown paper bag over the log may help reduce light levels and maintain humidity. Gardeners - Give the log plenty of soaking time & leave it alone. Don't mist it, except for pinning, if needed in areas with low humidity.

How do I know that all the mushrooms are edible and there are no poisonous mushrooms growing on my log?
We inoculated your log all over with high-quality shiitake spawn. The spawn was cultivated in a sterile environment by a professional mycologist (mycology is the study of fungi). The log is full of spawn so that nothing else can easily grow inside.

A healthy log has a strong immune system that fights off diseases and competing fungi. You might get a fungus on the bark, such as a brown or green fuzz or a hard, woody shelf mushroom, but it's highly unlikely that you'll get any fruiting mushroom other than a healthful, flavorful shiitake. If you do, you will recognize it as non-shiitake. Remove the mushroom. DON'T EAT IT. Dab or spray rubbing alcohol or hydrogen peroxide or apply heat (heat gun, candle flame -- being careful not to catch the bark on fire) to the area where it grew.

What if there is mold or some other fungus growing on my log?
Apply rubbing alcohol or hydrogen peroxide or apply heat (heat gun, candle flame -- being careful not to catch the bark on fire) to the wet or dry log, then scrape off the invader gently. Don't use bleach or fungicide. Small shelf fungi are common.

White fuzzy fungus is shiitake mycelia. If it's on the bark it's probably caused by too much humidity, such as being in the bag or box too long, or too much moisture on the bark. Shiitake on the ends is a good sign, meaning the log is ready to fruit. Shiitake may grow over the ends to seal the cuts. The mycelia will dry and can be peeled off, if desired. It will not interfere with fruiting. Green mold: The log is too wet. Treat it as above, let it dry, and move it to a place with lower humidity.

What if my log doesn't fruit on schedule?
The age of your log, the type of wood, and your water, light, and temperature all affect your mushroom production. Once your log has fruited, it HAS to continue producing mushrooms when it has the proper moisture, temperature, and light. If you don't get pinning and fruiting on schedule, start dropping the log on end or tapping with hammer after soaking, and try again every 2-3 weeks or so. Find a way to maintain cold temperatures during shocking. The two-month cycle is normal for most logs. But just like kids, some get their growth spurts earlier and some later. After fruiting regularly for a year or so, your log may take a break. Keep it watered, put it outside in spring or fall, and your 'shrooms will come back better than ever! Withholding water for 30 days may work, if the humidity is high (like in your bathroom) AND CALL - 1-800-792-0053, it's far more effective than emailing us because Doug can find out what's happening with the log by talking with your directly.

Keep the moisture level up with your maintenance soaking and you'll get increasingly bigger crops. You can always put it outside in the shade, on the ground, and Nature will fruit it for you spring and fall.

Successful mushroom growing is just good water management. Keep the moisture level up. Keep the log from killing temperatures and let it get day and night cycles and indirect light. Under our guarantee, we'll replace a living log that isn't fruiting - we won't replace a dried-up or dead log.

Our guarantee is that your log will grow mushrooms. Once it has even one mushroom on it, it will fruit again. This is really Nature's guarantee - the log is full of life and has to grow. With regular watering and very little care, your log will give you years of clean, fresh, delicious shiitakes.

Call us if you have questions. We mean it. We want both you and your log to be happy!