1. B Plus Growkit — 1200 cc
A 1200 cc kit of B+, the strain with the widest environmental tolerance in cubensis cultivation. It produces large, heavy fruit bodies with notably thick stems, and it keeps going in conditions that stop most other strains outright.
The number that matters: B+ continues to develop at temperatures as low as 15 °C. That is well below where any other kit on this page functions, and it is why B+ is the answer for a cold flat, an unheated spare room or a winter grow.
In the box: the colonised substrate container, a micro-filter grow bag and two paperclips. That is the complete list, and it is all you need. No syringes, no sterilising equipment, nothing to buy separately.
Legal status: Mushroom grow kits are sold legally in the Netherlands. Cultivating or possessing psilocybin mushrooms is illegal in many other countries, including Germany and the United Kingdom. We ship these kits as cultivation and study equipment; what you may legally do with one depends entirely on where you live, and that is your responsibility to check before ordering.
2. Specifications
| Specification | Detail |
|---|---|
| Strain | Psilocybe cubensis (B+) |
| Substrate volume | 1200 cc |
| Substrate | Fully colonised cased grain (rye), vermiculite and perlite |
| Price | €37.95 |
| Optimal colonisation | 24 °C to 27 °C |
| Optimal fruiting | 21 °C to 23 °C |
| Lower tolerance | Continues developing down to about 15 °C |
| Fruit bodies | Large and heavy, with thick robust stems |
| Character | The widest environmental tolerance of any strain we stock |
| Included | Grow box, micro-filter grow bag, 2 paperclips |
| Age restriction | 18+ only |
3. Tolerance
Every kit listing claims to be forgiving. B+ is the one where the claim is specific and testable, so here it is against the rest of our range:
| Strain | Where it stops |
|---|---|
| B+ | Keeps developing down to around 15 °C — slowly, but it keeps going. |
| Ecuadorian | Tolerates dips to about 18 °C. |
| Golden Teacher | Wants 23 to 25 °C; resilient to contamination rather than to cold. |
| Colombian | Stalls outright below 20 °C. |
| Thai | Prefers the warm end entirely — 21 to 26 °C for fruiting. |
3.1 What to do with that headroom
- Do not treat 15 °C as a target. It is the floor, not the plan. Colonisation still wants 24 to 27 °C and fruiting 21 to 23 °C for a good result.
- Expect it to be slower at the bottom of the range. Cold does not kill the mycelium, it stretches the timeline. Patience rather than intervention.
- The real benefit is overnight dips. Most flats fall several degrees at night, and B+ shrugs at that where other strains sulk.
- It also means fewer heat mats and fewer gadgets. One of the more genuinely beginner-friendly aspects of this strain is that it needs less equipment, not more.
The other thing B+ is known for is the fruit itself: large, dense mushrooms with thick stems, which makes a flush look substantial and handle well. Between the wide tolerance and the sturdy fruits, it is the kit we would suggest to anyone growing somewhere they cannot properly heat.
4. Setting it up
- Clean surface, clean hands, still air. Do this properly once rather than troubleshooting later.
- Twelve-hour cold soak with the box filled to the top and the lid back on.
- Drain it completely, lid held ajar, until it stops dripping.
- Into the filter bag upright, top rolled down twice and clipped.
- Warm, stable, indirect light. Nothing about this needs a windowsill.
- One short daily airing, then closed again.
4.1 Harvesting and later flushes
- Veil break is the harvest cue. It is the best trade between size and potency loss to spore production.
- Twist gently at the base of the stem.
- Take the entire flush in one session.
- Then re-soak for the next: cold water for twelve hours, drained completely.
4.2 If something goes wrong
- Mould shows as coloured patches — green, blue-green or grey. Once it is visible the substrate is lost; seal the bag and dispose of it without opening it near another kit.
- Bacterial contamination announces itself by smell, sour or ammoniac, often before you see anything.
- A soft grey web over the fruits is cobweb mould, and increasing air exchange straight away sometimes saves the flush.
- Blue marks on handled stems are oxidation, not infection, and are entirely normal.
5. Before you use them
5.1 Preparation
- Someone stays sober and stays with you. They need to know what you took and roughly how much.
- Be seated or lying down before the first effects. Postural control is not reliable.
- Make the space safe first. No flames, no sharp or breakable objects, no stairs, no open windows.
- Keep a trip stopper to hand. Most are never opened; having one still helps.
- Nothing combined with it. No alcohol, no cannabis, no other substance, prescribed or otherwise.
5.2 Do not use these if
- You must be over 18.
- Do not use if pregnant or breastfeeding.
- Do not use if there is psychosis, schizophrenia or bipolar disorder in your own history or in your close family. Psychedelics are capable of precipitating episodes in people already predisposed to them, and this is the caution we would least like you to skip.
- Do not combine with alcohol, cannabis, antidepressants, MAOIs or any prescription medicine without asking a doctor.
- Do not drive or use machinery for the rest of the day.
- The law varies from country to country and has changed repeatedly. Check yours.
Fifteen degrees is a floor, not a target. What it buys you is a kit that shrugs off the overnight dip in an ordinary flat.
- A 1200 cc B+ kit — the widest environmental tolerance of any strain we stock.
- Keeps developing down to around 15 °C, well below any other kit on this page.
- Colonisation 24 to 27 °C; fruiting 21 to 23 °C for the best results.
- Large, heavy fruit bodies with thick, robust stems.
- The sensible choice for a cold flat, an unheated room, or a winter grow.
- Kits are legal in the Netherlands; cultivation is illegal in many other countries. 18+ only.
- Order before 16:00 on weekdays for same-day dispatch in plain, unmarked packaging.
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