CH 05 Growing Updated
Why Penis Envy is harder to grow than other cubensis
Why Penis Envy and APE grow slower and drop few spores, what one agar study measured, and how a ready-to-fruit grow bag from the Netherlands changes that.
- APE plate cover, day 25, PDA
- 30.5 %
- B+ plate cover, day 25, PDA
- 100 %
- Fruiting temperature, bag manual
- 23 to 27 °C
- Grow level, shop card
- advanced
Penis Envy is harder to grow for two reasons that growers have described for years and that one study now partly measures. Its caps often stay closed, so it drops few spores and is usually kept going by cloning. And its mycelium grows slowly: in a 2025 agar study, Albino Penis Envy had covered 30.5 percent of a potato dextrose agar plate after 25 days, where B+ had covered the entire plate (Pepe et al., 2025).
This page explains both, and what they mean for a ready-to-fruit grow bag. The legal status of growing differs per country; see the law page before anything else. In the Netherlands, buying a grow bag is legal, and the mushrooms become illegal as soon as they appear.
Few spores
A cubensis normally opens its cap, tears the partial veil and drops a dark spore print. Penis Envy caps stay small and often closed, and the shop card for Dutch-Smart's APE grow bag says plainly that "spore production is limited". The peer reviewers of the 2021 Penis Envy genome paper repeated the grower account of a mutant with "missing partial veil", preserved "via clonal propagation" (McKernan et al., 2021).
For a grower, few spores means few starting points, and grower accounts describe the line as kept mostly by cloning: taking tissue from one fruiting body, which copies that individual. In a ready-colonised grow bag, the producer has already done that work.
Slow mycelium: what was measured
Researchers at the University of Guelph in Canada compared four cultures on several agar media over 25 days: Albino Penis Envy, B+, JMF and the wood-loving species P. allenii. They chose APE because the grower literature calls it "among the slowest growing P. cubensis genotypes", and B+ because it is described as among the fastest (Pepe et al., 2025).
| Culture | Malt extract agar, day 25 | Potato dextrose agar, day 25 |
|---|---|---|
| Albino Penis Envy | 95.8 % | 30.5 % |
| B+ | 100 % (full by day 20) | 100 % (full by day 20) |
| JMF | 64.2 % | 55.4 % |
Share of the plate surface covered, first experimental series. In a second series, APE reached 72.3 percent on potato dextrose agar and failed to colonise one of the other potato dextrose variants at all.
Two conclusions in the paper matter beyond the lab. B+ grew well on almost anything, while APE showed "substantial differences in growth rates between media". Slow genotypes, in other words, are also the picky ones. This was mycelium on agar, not fruiting in a bag; no study has yet timed Penis Envy from colonised bag to harvest.
What a ready-to-fruit bag takes off your hands
A grow bag such as the APE grow bag contains 2,100 g of substrate that the producer has already fully colonised. Spores, cloning, agar, grain spawn and the slow colonisation stage all happen before it ships. What is left is the fruiting stage, and that is where Penis Envy still behaves differently.
The general grow bag manual from Dutch-Smart asks for:
- a bright place with indirect light, never direct sun;
- a constant 23 to 27 °C, never above 27 °C;
- the bag closed until the first pins appear, then a slit at the top for fresh air;
- clean hands and tools at every step;
- harvest before the caps open completely.
The strain card for APE adds that "slow growth does not mean the bag has stalled", that pins appear later than with Golden Teacher or B+, and that you get "fewer, but more compact mushrooms". It advises leaving the setup alone while the mycelium looks healthy and keeping the elastic band on to prevent side pins. Because the caps often stay closed, judging the moment to harvest is harder than with a cultivar that opens its veil on cue.
Contamination
Healthy mycelium is white to yellowish-white. Green, black, red or pink patches are contamination, according to the bag manual, and cannot be saved. The manual warns against opening the bag before pins appear and against handling it more than necessary.
Storage before setting up
The APE strain card advises setting the bag up as soon as it arrives. If that is not possible, it can be kept briefly at 6 to 8 °C, cool and dark, and never frozen.
Which bag to choose
If you have never grown a cubensis, the shop itself points to Golden Teacher or B+ as the easier choice and labels APE "advanced". The grow bag guide compares the options side by side.
