For a first grow, the sensible choice is a standard, fully colonised kit of a common Psilocybe cubensis strain. Size matters more than the strain name: a larger block gives more per flush, while the name on the label says little you can rely on about strength. Laboratory studies find large differences between strains, but also between single mushrooms of the same strain and between flushes of the same kit.
Kit types side by side
| Type | Block | Suits | Notes |
|---|---|---|---|
| Standard (1200cc) | fully colonised, medium | a first grow | two to four flushes; easiest to keep warm |
| FreshMushrooms XP | fully colonised, no fillers | a first grow | comes with a step-by-step leaflet |
| XXL (2100cc) | fully colonised, large | a second grow | more per flush; needs the same care |
| Hybrid kits | fully colonised | growers who want a specific named cultivar | parentage not documented in scientific literature |
| Copelandia (Hawaiian) | Panaeolus cyanescens, a different genus | experienced growers | stronger per gram than most cubensis, according to the shop |
All of these arrive ready to fruit. Kits that start from a spore syringe or a liquid culture are a different hobby: you prepare and sterilise your own substrate and wait weeks before anything grows. Dutch-Smart sells both, but the rest of this site is about ready-to-grow kits.
Standard kits for a first grow
A 1200cc kit is enough to learn what your room does to temperature and humidity, and it gives a usable harvest when it works. Choose the strain by availability; the section below explains why.
Golden Teacher - 1200cc Mushroom Grow Kit
€33.95Dutch-Smart
Stock ref DS-1574
B+ 1200cc Mushroom Grow Kit
€33.95Dutch-Smart
Stock ref DS-2726
Mazatapec - 1200cc Mushroom Grow Kit
€33.95Dutch-Smart
XXL kits
The XXL kits hold a 2100cc block. Dutch-Smart describes the total yield across all flushes as considerably higher than from a standard kit; it does not give figures, and neither do we. The care is the same as for a small kit, so the step up makes most sense once a standard kit has worked for you.
Golden Teacher XXL - 2100cc Mushroom Grow Kit
€49.95Dutch-Smart
Stock ref DS-2765
McKennaii XXL - 2100cc Mushroom Grow Kit
€49.95Dutch-Smart
Stock ref DS-2925
B+ XXL - 2100cc Mushroom Grow Kit
€49.95Dutch-Smart
What strain names tell you
Almost every mushroom kit in a Dutch smartshop is Psilocybe cubensis. Names such as Golden Teacher, B+, McKennaii, Mazatapec, Thai or Treasure Coast are cultivar names from the growing hobby. Some refer to the place where the original culture is said to come from, some to a person or a look. None of them is a botanical category, and the origin stories are rarely documented.
What the chemistry shows:
- A 2024 study measured five strains with the same method. Total psilocybin plus psilocin ranged from 1.36% of dry weight in Creeper to 0.88% in Thai, with B+ at 1.13% (Goff et al., 2024).
- A 2026 study grew 14 cubensis strains under identical laboratory conditions. Total tryptamines differed more than 7.8-fold between strains, from 2.62 to 20.65 mg per gram, and single mushrooms of the same strain had coefficients of variation of 13 to 23% for psilocybin (Sharchaton et al., 2026).
- An older study followed cultures over repeated flushes. Psilocybin varied by up to a factor of four from flush to flush without a clear upward or downward trend, and psilocin was generally absent in the first flush (Bigwood and Beug, 1982).
So strains do differ, sometimes a lot, but the published studies did not test most of the names you see in shops, and the variation within one strain is large. We found no laboratory measurement of Golden Teacher or McKennaii. Read any claim that one kit is "twice as strong" as another as marketing, and assume every harvest is a little different.
Hybrid kits and Royale Flush
Hybrid kits carry names such as Jack Frost or Marshmallow and are sold as crosses between cubensis cultivars. The same caution applies: the name is a brand, not a measurement. Royale Flush is another line of fully colonised kits with familiar strain names.
Jack Frost - Hybrid Mushroom Grow Kit
€49.95Dutch-Smart
Stock ref DS-4668
Golden Teacher Grow Kit – Royale Flush
€37.95Dutch-Smart
Copelandia: a different species
The Hawaiian Copelandia kit grows Panaeolus cyanescens, which belongs to a different genus than cubensis. In a German study of seized mushrooms, P. cyanescens had the highest psilocybin and psilocin levels of the samples tested (Musshoff et al., 2000). Dutch-Smart lists it for growers who already have experience with standard kits. It forms slimmer, more fragile mushrooms than cubensis.
Questions to ask before you order
- Can you set it up the day it arrives? Fresh kits should not wait. If you are away, order later.
- Where will it stand? Measure the temperature there at night first. A cold room needs a heat mat with a thermostat; see the grow guide.
- Is it legal where you live? Read the legal notes before you order. Shops ship from the Netherlands, but the law that applies is the law where the kit grows.
When the kit is running, the contamination page helps you judge what you see, and harvest and drying covers the end of each flush.