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North Spore buy on Amazon makes a better kit for anyone planning to grow more than twice. Back to the Roots check current price makes a better kit for anyone who wants to open a box, mist it a few times, and eat mushrooms without reading a FAQ. Those two sentences cover 80% of the North Spore vs Back to the Roots mushroom grow kit decision. The rest is just numbers and specifics.
I ordered both the North Spore Blue Oyster and the Back to the Roots large oyster kit to run alongside my hydroponic setup. My North Spore blocks haven’t fruited yet (I’m documenting that in real time, so I’ll have actual flush weights when they land), but the specs, the block construction, and what growers have reliably reported over years of forum discussion give me enough to work with for a real comparison. And that community knowledge, built up over thousands of grows, is worth taking seriously even without my own flush weights in hand yet.
Quick Answer: North Spore is the better kit if you want 3+ flushes, more species variety, or a 4 lb block that tolerates missed misting days. Back to the Roots is the better kit for total beginners who want cheap, fast, and simple with low setup friction. The misting habits of the person buying it matter more than the brand name.
Side-by-Side Specs
| Spec | North Spore Blue Oyster | Back to the Roots Large Oyster |
|---|---|---|
| Substrate weight | 4 lbs | ~1-1.5 lbs (box format) |
| First-flush yield range | 0.5-2 lbs | 0.25-0.75 lbs (estimated) |
| Guaranteed flushes | 1 (replacement if no fruit in 2 weeks) | Not formally guaranteed |
| Misting sessions/day | 1-2x (2-3x in dry conditions) | 1-2x |
| Amazon price | ~$34.99 | ~$20-25 |
| Price per lb at median yield | ~$35/lb | ~$30-50/lb |
Back to the Roots Organic Oyster Mushroom Grow Kit ...
Compact oyster mushroom kit producing 3-4 servings per crop within 10 days with daily misting, ideal for indoor growing year-round.
~$17.97
North Spore Organic Pink Oyster Mushroom Grow Kit, 4 lbs
4 lb sawdust-based kit produces 0.5-1.5 lbs pink oyster mushrooms in 14-21 days with daily misting on countertops
~$24.99
North Spore Organic Blue Oyster Mushroom Grow Kit, 4 lbs
4 lb blue oyster kit produces 0.5-1.5 lbs of mushrooms in 14-21 days, ideal for indoor cultivation with minimal experience required.
~$24.99
Back to the Roots Organic Mini Mushroom Grow Kit ...
Ready-to-use mushroom kit produces 3-4 servings per crop in 10 days with twice-daily misting, ideal for indoor beginner growers
~$14.99
The price-per-lb math is the uncomfortable part nobody wants to publish. Organic oyster mushrooms at a grocery store run around $8-12 per pound. At 1 lb of yield from a $35 North Spore kit, you’re roughly breaking even. At the lower end of yield (half a pound), you paid $70 per pound of mushrooms. That’s not an argument against grow kits, but it’s worth being honest about. The value is freshness, species you can’t find at stores, and the experience of watching something fruit on your counter. If you’re doing it purely for cost savings, the math doesn’t work in your favor. I extended it across four kits in my price-per-gram breakdown .
The Misting Variable Is the Whole Game
This is the part that separates a good first grow from a frustrating one, and no other comparison article covers it honestly.
Back to the Roots uses a smaller box format with less substrate mass. Less substrate means it dries out faster. When misting gets skipped for two consecutive days, the block surface dries out faster than the mycelium can recover, and pinning just doesn’t happen. With consistent daily misting, success rates climb a lot. That’s not a small difference. It’s the difference between eating mushrooms and wondering why nothing happened.
North Spore’s 4 lb block holds moisture longer. Missing a single day isn’t ideal, but it’s survivable. The block size buys you a little forgiveness that the smaller Back to the Roots format doesn’t have.
Both kits recommend 5-10 sprays once or twice daily. In a dry apartment with AC running in summer, twice daily is the floor, not the ceiling. I run my AeroGarden in the same kitchen, so humidity isn’t terrible, but I’m still misting the blocks morning and evening to be safe.
The honest frame: if your lifestyle involves occasional forgotten tasks, North Spore’s larger block is more tolerant of that. But if you’re the kind of person who’ll mist consistently and this is your first time growing anything, Back to the Roots removes a lot of friction. And if you’re someone who has killed a houseplant by forgetting it existed, that distinction matters more than any spec on the comparison table.
🌿 Best for Serious Growers
North Spore Organic Blue Oyster Mushroom Grow Kit, 4 lbs
4 lb blue oyster kit produces 0.5-1.5 lbs of mushrooms in 14-21 days, ideal for indoor cultivation with minimal experience required.
Check Price on AmazonFlush Count and What That Actually Means
North Spore formally guarantees one flush and offers a replacement kit if nothing fruits within two weeks. Most growers who follow the soak protocol get a second flush, and a third is achievable with patience. Up to five flushes is possible with good technique, though realistically three is a reasonable ceiling for home growers.
Back to the Roots oyster kits typically produce two flushes. That’s consistent across years of grower reports, and it’s a decent outcome for a $20-25 kit. You’re not leaving a lot on the table there.
The soak protocol between flushes matters more than most kit instructions suggest. For North Spore oysters, soak the block cut-side down in water for up to an hour, then pat it dry and return it to the bag. For North Spore lion’s mane (a different kit entirely), the soak is only 10-15 minutes because lion’s mane mycelium is more delicate and doesn’t tolerate prolonged submersion. For Back to the Roots, a few hours of soaking works well before setting it back out. When a block still refuses to fruit afterwards, work through my kit troubleshooting guide .
One thing to know: the Back to the Roots large kit and the Back to the Roots mini kit see on Amazon are different mushroom species, not just different sizes of the same thing. The mini is a different grow experience. Worth knowing before you accidentally buy the wrong one as a gift.
North Spore also sells a Pink Oyster kit check price on Amazon alongside the Blue Oyster. Pink oysters fruit faster and in warmer temperatures, which makes them a better choice for summer growing in a kitchen that doesn’t have aggressive AC. Blue oysters prefer slightly cooler conditions (around 60-75°F), which is where most apartments naturally land.
What to Do With a Spent Block
Nobody covers this. Every comparison article ends at “enjoy your mushrooms” and ignores the brick of used sawdust sitting on your counter afterward.
Three options, in order of effort:
Compost it. A spent block breaks down well in a compost pile. The mycelium has already broken down much of the sawdust into simpler compounds, so it’s actually good compost feedstock.
Bury it outdoors. This one’s legitimately useful if you have any outdoor access, even a small garden bed or a patch of dirt. Growers who’ve buried spent oyster blocks in wet soil under a deck or in a shaded garden bed have gotten additional small flushes for free. The block still has residual nutrition and active mycelium. This isn’t guaranteed, but it costs nothing to try.
Soak and attempt a late flush. If you’re not sure whether the block is truly spent, give it one more long soak (several hours for Back to the Roots, up to an hour for North Spore oysters) and return it to a humid spot. You might get a small final flush that wasn’t worth writing off.
I don’t have outdoor space so composting is my only real option, but the burial trick is clever and worth knowing about if you have a garden. So if you do have a patch of outdoor dirt, don’t skip that option before you toss the block. And if you’re not sure the block is done, a final soak costs you nothing but a few hours of patience before you give up on it.
The White Stuff Question
The most common beginner panic with any mushroom kit is white fuzzy growth appearing on the block. Almost always, it’s mycelium. Oyster mycelium can form a thick, leathery white mat and it looks alarming if you’ve never seen it before. It’s normal. It’s good. It means the block is active.
What you’re actually looking for is color. Black, green, or orange patches on the block indicate potential contamination, and that’s when you’d contact the kit maker with a photo. Healthy blocks smell pleasantly earthy, sometimes described as mushroomy or forest-like. If something smells wrong, trust your nose before your eyes.
Both North Spore and Back to the Roots have reasonably responsive customer service. North Spore offers a replacement guarantee if the kit fails to fruit within two weeks of activation.
This article is part of my Gourmet Mushroom Grow Kits: The Complete Guide , a complete resource for growing gourmet mushrooms on your counter.
Frequently Asked Questions
How much yield can I expect from a mushroom grow kit?
Most kits produce somewhere between 0.75 and 1.5 lbs of fresh mushrooms across multiple flushes, though it varies considerably by species and how well the grow goes. North Spore officially puts first-flush yield at half a pound to 2 lbs. A well-managed block in a typical home environment tends to produce 7-8 oz per flush over two flushes, which is a realistic target to plan around.
Can you reuse the Back to the Roots mushroom kit?
Yes. Soak the block in water for a few hours, then set it back out the same way you started it. The oyster kit supports multiple flushes this way, and most growers get a second harvest without much trouble. There’s enough nutrition in the substrate for at least two flushes, sometimes more if conditions are good.
Are mushroom grow kits worth buying?
Financially, not really. At $8-12 per pound for organic oyster mushrooms at retail, and kits running $20-35, you’re roughly breaking even at best. The actual value is in growing species you can’t find at a regular grocery store (pink oyster, lion’s mane), eating them at peak freshness within an hour of harvest, and the experience of growing something unusual. The common take among people who’ve tried both approaches is that it’s more interesting experiment than cost-saving measure.
When should I harvest oyster mushrooms from a grow kit?
Harvest when the cap edge is still slightly curved under and before caps flatten out or become concave. Oyster mushrooms can double in size daily once they start moving, so check them every morning. Grab the entire cluster at the base and twist gently to pull it free. If you wait until caps are fully flat, they’ll release spores and the white powder all over your counter is harmless but messy.
How often do you mist a mushroom grow kit?
North Spore recommends 5-10 sprays once or twice daily. In a dry apartment or with AC running, lean toward twice daily as the minimum. Consistency matters more than quantity per session. Set a phone reminder if you need to.
My own North Spore blocks are still in the early stages, and I’m tracking everything for a full flush-by-flush post once I have real weights to report. I also break down nutrient and substrate costs for anyone who wants the full financial picture. For now, if someone asked me which kit to buy today: Back to the Roots for a curious first-timer who wants quick and low-stakes, North Spore for anyone who’s actually interested in getting multiple grows out of it. The block size alone justifies the price difference if you’re going to follow through.