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Our beginner-friendly, USDA-certified organic oyster mushroom countertop kits make growing your own mushrooms so easy. Just open the front of the box, cut an “X” into the plastic bag, spray with water 2-3 times a day, and watch them grow!
Why we love them:
Blue oyster mushrooms are velvety, savory, and mild and pair perfectly with just about any recipe! Blue oysters are a staple here at North Spore (going all the way back to when we began as an urban farm.) After perfecting our blue oyster kits over the years, they’ve become one of the easiest kits to get multiple fruitings from and should produce a second flush of mushrooms (or more!)
Skill level
Beginner
Grow location
Indoors
Grow speed
2 weeks
Certifications
USDA certified organic
Kit shelf life
6 months (refrigerated)
Kit dimensions
10"(H) x 5"(W) x 5"(D)
Kit weight
4 lbs
Key Features:
About the kit:
Our blue oyster mushroom kits are reliable producers and tend to yield large flushes of beautiful light grayish-brown to deep blue-gray mushrooms when given adequate humidity. With continued proper care, you should be able to get multiple flushes. (We 100% guarantee your first flush of mushrooms, but hope you'll try for 2 or 3!)
That's not mold, it's mycelium!
Your kit includes an amended sawdust block fully colonized with mushroom mycelium. It may appear covered with a soft, white, mold-like substance - that's the mushroom mycelium! It is completely normal. The mycelium of some species is more prominent than others.
Additional Details:
1) Inside this box is an amended sawdust block that has been completely colonized by mushroom mycelium. Open the front of your kit along the perforated line and dispose of the remaining cardboard.
2) Slice an 'X' into the plastic underneath with a sharp knife or scissors.
3) Lift open the top of your box to find the sprayer and instruction booklet. Fill the sprayer with tap water and generously spritz the plastic where you sliced your 'X' shape. Spritz your kit at least twice daily - more if you're in a particularly dry climate. (If your mushrooms start to grow but dry up and die, your growing conditions may be too dry and you should make a humidity tent!)
4) Place your kit in the most humid part of your home and outside of direct sunlight. We suggest putting it on a kitchen counter close to a sink. The mushroom mycelium will sense the oxygen in the air and produce mushroom 'pins,' another term for 'baby mushrooms.'
5) It usually takes 5-14 days for pins to form. Once pins begin to form, mushrooms will grow quickly. So when you spot your first pins keep an eye on them. The warmer the environment the faster they will grow. Mushrooms should be ready to harvest 2-5 days after pin formation.
If you're not ready to use immediately, your Blue Oyster Spray & Grow Kit can be refrigerated or stored in a cool dry place, out of direct sunlight, for up to 6 months.
The classic North Spore recipe is to chop the blue oyster mushrooms and sauté them in a heavy pan on medium heat with butter, garlic, and loads of fresh thyme and rosemary (or whatever other herbs you happen to have on hand!). Cook until the mushrooms have released their liquid, then continue cooking until that liquid has cooked off and the mushrooms begin to brown. This can take from 20-30 minutes. Deglaze your pan with a splash of white wine, reduce once more, and finish with a touch of heavy cream. Season generously with salt.
USDA Certified Organic
The spawn used in our mushroom kits is grown on organic grain and made with organic cultures from our own culture bank. Our kits are handmade from a blend of non-GMO woods and supplements from farms and forests in New England and North America.
Simply take a trash bag or other loosely fitting plastic bag and put PLENTY of 1/2 inch holes in it (THIS IS IMPORTANT: Mushrooms exhale CO2 and inhale oxygen. They will suffocate themselves if there isn’t adequate airflow! Blue oysters that look stringy or strange are usually growing that way because they need more air!). Spray the slice at least once per day with the included spray bottle. If you choose to use a humidity tent make sure to spray the inside of the tent once per day to maintain humidity.
If you’re going to consume home-grown mushrooms, make sure to cook your fresh mushrooms thoroughly with heat. If it is your first time eating this species, it is best to start with a small amount to check for allergies, even if cooked.
Mushrooms grow spores as they develop. This is a natural means of reproduction. This is when people with allergies or compromised immune systems may want to consider putting fruiting mushroom kits outdoors or in a well-ventilated area. Spores in mushrooms sometimes cause respiratory irritation. In rare cases, spores may also cause irritation for some non-allergic or non-immunocompromised mushroom growers. If you are one of them, it is recommended to reduce the overall spore load by harvesting mushrooms while they are still in their younger growth stages.
What is shelf life? How should I store before use?
Inside your Spray & Grow Kit is a living organism, so we recommend activating it upon receipt. If you need to wait, you can store them in a cool, dry place out of direct sunlight or in the fridge for up to 6 months.
NOTE: Pink oyster mushrooms don't tolerate temperatures below 40 degrees F, so skip the fridge with these and instead opt for something else like a cellar, pantry, or cool porch tucked away from the sun.
All of the species used in our kits are very vigorous and viable, so after storing for a few weeks, they may start fruiting in the bag! It's no issue, but some recipients can be surprised or concerned which is why we have activation and storage recommendations.
Should I take the block out of the box and bag?
Our Spray & Grow Kits should stay in the bag (and inside the box) while they grow.
After removing the front panel of the box along the perforated lines, cut an X into the exposed plastic. Enough oxygen gets to the block through this cut and it directs the mushrooms to form there. Remember to leave the plastic flaps of the X on the bag, they'll help to keep moisture in. The mushrooms will easily grow out of the sliced X section, so no need to open it up more as they fruit.
How often (and how much) should I water my kit?
You don’t need to empty the bottle each time you spray, but it is important to get the area where you cut open the bag nice and damp! Try 5-10 sprays each time. It can take a little trial and error to get the frequency and amount just right. If the surface of the block seems very dry the next time you spray it, you should give it a bit more water or water a bit more often. If you run AC or live in an arid climate, using a humidity tent can be useful to prevent your block from drying out.
Why did my kit start then stop growing?
Usually, mushroom pins stop growing when there isn't enough humidity around the block. Don't panic! Your mushroom kit still has all the food needed to produce mushrooms. Simply pick off the dried-up pins, wait one week, letting the block dry out on a plate. Then, soak the block for 20 minutes in cold water, drain all the water out of your kit (species that grow in the bag) and start the process over. If you didn't use a humidity tent the first time then it may be helpful the second go around. It creates a moist microclimate that your block should thrive in.
When you start to see baby mushrooms form (pinning), you can remove the bag and keep misting the block. Make sure to keep a close eye on the kit. Spray 2-3x daily with water to keep it hydrated.
When should I harvest my mushrooms?
The image on the front of your Spray & Grow Kit box shows the mushrooms at their ideal stage of growth for harvesting. The general rule is that mushrooms should be harvested before their caps flatten or become concave. In the case of lion's mane, before they become yellowed and mushy. Unlike plants, mushrooms grow incredibly fast, sometimes doubling in size each day. Make sure to keep a close eye on your kit so you don't miss the opportune time to harvest!
We like to harvest oyster mushrooms right before their caps begin to flatten out, while the edge is still a little curved under. At this point, the mushrooms have almost grown to their full size and will store better than mushrooms harvested later. You can definitely pick and eat mushrooms after the cap has flattened out, but they won’t keep as long and are more brittle.
Lion’s mane doesn’t have caps and gills, but rather teeth. When they’re young, they form as dense round balls, sometimes growing more mounds and lumps in maturity. The length of their teeth or spines can be used as a good indicator of when to harvest. We like to pick them when teeth are ¼-½” long before any yellowing.
To harvest, reach your hand around the base of the mushroom cluster and twist. This motion should be enough to pop your mushrooms off the block. You can also use a knife if you want, too! Remove any extra loose debris on the block before starting to spritz again for a second flush. Your first flush could produce anywhere between ½-2 lbs. of mushrooms!
If mushrooms become dried out, moldy, or look unappetizing in any way chances are they weren't harvested early enough. You can send us a photo to see what might have happened. Stringy mushrooms with long stems and little caps probably are in a high CO2 environment. Give them some air or even try a fan!
What do you mean by 'fruiting' and 'flush'?
The word fruit can be very specific, referring to foods like berries and apples, or a bit more general to refer to how an organism reproduces. So tomatoes and rosehips are the fruits of those plants; they contain the seeds. Likewise, mushrooms are the fruits of a fungus; they contain spores. So when a fungus starts to produce mushrooms, we call that fruiting.
Specifically, mushrooms are the reproductive structure of the fungus. The block in your kit is primarily comprised of mycelium (the vegetative body of a fungus), and it's food (a bag full of supplemented sawdust). As the mycelium grows, consuming the sawdust mix, it uses up the nutrients available in the bag. When it's fully established, has run out of nutrients or experiences other environmental cues like a temperature or oxygen shift, that's a cue for the fungus to fruit and produce mushrooms so that it can move on to another food source.
A flush refers to the production of multiple mushroom fruit bodies at one time. Many of the fungi we cultivate tend to produce many mushrooms simultaneously - this is known as a 'flush' of mushrooms.
How many flushes will one kit produce?
We guarantee at least one fruiting of mushrooms off your kit, but depending on the species you choose to grow it is likely you will get a second, third, fourth, or even fifth fruiting with care and patience. Growing mushrooms is an art, and it takes skill to be good at it. Be patient, follow the instructions carefully, and try to maintain a humid environment for your kit and you should succeed.
In terms of yield, you can usually expect your first flush to be somewhere in the range of 1/2 of a pound to 2 lbs. This varies significantly species to species, environment to environment. It depends greatly on how much care you put into maintaining your kit! Each subsequent fruiting will likely be smaller as the fungi use up nutrients in the substrate.
How do I harvest my mushrooms?
Hold the cluster near the base and spin them. If you'd rather use a knife and cut them, that's fine too! Clean off any loose bits from the kit before continuing to spray and cut off any bits of sawdust from the block on your mushrooms before cooking and eating them.
Do I need to cook my mushrooms?
Yes, you should make sure any mushrooms you eat are thoroughly cooked. Mushrooms contain a compound called chitin which is difficult to digest. Chitin also occurs in arthropod shells giving them strength and flexibility. It readily breaks down with heat, so cooking mushrooms makes them easier on our bodies.
Using a Spray & Grow Kit
Growing mushrooms at home is easier than you think, especially with a table top setup like one of our Spray & Grow kits! In 2 weeks or less, you'll have your first harvest right from your kitchen counter! We've compiled these resources to help you every step of the way. We hope this is just the start of a long and fruitful mushroom journey.
Getting started
In this video, we show you how to get your Spray & Grow mushroom kit set up for success in 4 simple steps.
Set up tips & tricks
Get your kit ready
After you receive your Spray and Grow Kit and carefully remove the front panel, check to see that the kit inside is intact. Sometimes they're jostled in transit and break apart - but not to worry! Gently press it together and let your kit sit for a few extra days to recoup before opening up the bag. You'll soon see the mycelium, resilient as ever, bouncing back from its trip to your home.
Meet the mycelium
Speaking of mycelium - that fuzzy, white stuff growing on your kit isn't mold! That's the vegetative form of a mushroom, known as mycelium. What that looks like for different species can vary: blue oyster can have yellow orange droplets, pink oyster can have a rosy hue, golden oyster is thick and white, and lion's mane is light and wispy!
Humidity check
If you live in a dry or arid climate, it's a good idea to cover your kit with a humidity tent to help keep moisture levels high. Take a trash bag or other large loose bag and cut lots of ½” holes throughout - mushrooms need fresh air to form correctly! Drape the bag over your block and mist the inside of the bag every day. When you start to see baby mushrooms form (pinning), you can remove the bag and keep misting the block.
Growing, Harvesting & Cooking
In this video, we show you how a kit grows. Plus, you'll learn tips on harvesting and cooking mushrooms from your Spray & Grow kit.
Growing tips & tricks
Environment
Once you've started your mushroom kit, the three things you need to focus on are hydration and air flow and light. Mushrooms need a humid environment, some oxygen and natural light to grow well and develop their rich hues. Stringy mushrooms want more air, dry mushrooms need more humidity, and pale mushrooms need light or are a bit past prime!
Moisture
Make sure you're spraying them regularly and add a humidity tent if they could use some extra moisture. It's best to keep them out of the cupboard or closet. They make fantastic centerpieces to a dining table or as a feature on your kitchen counter. That way they get a little dappled sun, some gentle air circulation, and you can dote on them at every coffee break.
Pinning
Once activated, your kit should start pinning within 6-10 days. From there, it usually only takes 4-5 days for your mushroom kit to produce it's first full flush! When you start to see baby mushrooms form (pinning), you can remove the bag and keep misting the block. Or, you can keep just leave it in the box and water daily.
From 'pin' to 'flush'
Getting multiple flushes
After first flush
After you’ve harvested your first flush of mushrooms, continue spraying your kit as you were. If it's looking a bit dry, you can cover it with a humidity tent. It's important do keep it hydrated throughout the process. There's no need to take the block out of the bag or cut a second X in it. It may a little longer for mushrooms to appear every subsequent fruiting. In around 2-3 weeks, you should start to see baby mushrooms (pins) forming again.
Kit reboot
If by then there's no progress, you can soak your block. It’s possible during the first flush the kit got a little too dry. Take your block out of the box and set it cut side down in a bowl of water. Most species only need to soak for 20 minutes. If you have a Lion’s Mane kit, soak your block for 5-10 minutes and keep an eye on it. Lion’s Mane mycelium is very fine, so these blocks tend to break apart if soaked for too long.
Post-soak
After soaking, let the block drain by leaving it cut side down for another 10 minutes or tip it around to let extra water run off. You don't want to leave standing water in your bag. Pat your block dry before placing it back in the box with the cut side facing out or skip the box and leave the block cut side up and keep spraying it 2-3 x per day.
Giving your kit a second life outdoors
Did you know your kit has multiple lives? In this video, we'll walk you through planting your Spray & Grow kit outdoors.
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