The Zapotecorum Grow Guide
Prepared by: Chan
Date: jun 19 2023 last edite
Table of Contents
1.0 - Description, distribution, habitat 3
2.0 - Strain Selection and Development, and Agar Work 5
Overview
Psilocybe zapotecorum is one of the largest and most potent psilocybin mushrooms in the neotropics. The mushrooms can be over 26 cm tall, with 13cm diameter caps. All parts of the mushroom rapidly bruise deep blue-black when handled.
Cap
The caps are umbonate, conical to convex, and occasionally expand open to planar. The cap margin is scalloped when young, and can become wavy with maturity. The cap is hygrophanous, typically yellow to carmel brown when wet, pale yellow when dry, and with age or poor weather conditions the cap turns black. The texture of the caps is fleshly relative to the stem. The gills start as a creme color when young, giving way to violet as spores develop and mature. The gills can have a sinuate, adnate, or subdecurrent attachment to the stipe.
Stem
Veil remnants are rarely seen on P. zapotecorum, as the veil breaks when the mushrooms are still young and disappears. The most prominent feature of the stem of P. zapotecorum are the pronounced floccules, giving the stems a shaggy appearance. The central cylindrical stem is white when fresh, sometimes with reddish, yellow or tan tones. Cutting the stem reveals a hollow brown inside. The stem texture is quite fibrous compared to other Psilocybe. Sometimes a pseudorhiza can be found at the base of the stem, extending into the substrate.
Organoleptics
The fruit bodies taste and smell cucumber-radish farinaceous, and have a lasting sour taste that is unlike simple organic acids. The sour taste when strong can be felt localized to parts of the palette, like the back-sides of the tongue, and lasts longer than typical sour tastes. While not noted in wild strains or in field guides, the cultivated strain ‘La Martinica’ also has a tropical terpene-like essence combined with the sour taste, lasting for hours after consumption. The strength of the organoleptic profile can vary, and it has been suggested that maybe the taste potency can be correlated to the psychoactive potency, though this has not been explicitly shown.
Microscopic Features
The spores of P. zapotecorum are inequilateral symmetrical and ellipsoid to fusoid in shape, 5.9-6.9 µm long, 3.6-4.1µm wide. By eye the spore color is purple to purple-brown. The spores have truncated germ pores, and acute apiculuses. The cheilocystidia are hyaline, polymorphous, langeniform, ampulliform and sometimes furcate. Pseudocystidia are gray, polymorphous, sublageniform, subventricose, subpyriform, sometimes furcate and sometimes submiliform. They are usually enlarged at the middle, slightly tapered or rounded at the base with a short or long neck to the apex. The pileipellis is hyaline and subgelatinous. The pileus trama mycelium is hyaline. The lamellar trama is regular to subregular.. The pleurocystidia are hyaline, clavate, mucronate and sublecythiform.The basidia are four-spored.
Occurrence
Psilocybe zapotecorum is found across the neotropics, from Mexico to Brazil. Its ecology varies depending on the local region. In Mexico P. zapotecorum is one of the ‘derrumbe’ mushrooms, found fruiting at landslides, washouts, or human disturbances like roads and trails in or near cloud forests. It is typically growing out of clay soil, feeding on buried woody debris. Oftentimes it is found near rivers, streams, or waterfalls, where humidity is high. It can fruit scattered or abundantly, sometimes found in dense caespitose clusters.
Violet brown gills strain Jalisco Elisa (foto: Alan Rockefeller) | characteristic white scaly stipe |
Wild Veracruz
2.0 - Strain Selection and Development, and Agar Work
Three tested and successful strains from different states in Mexico will be compared throughout the grow guide:
- Popocatépetl
- Elisa Jalisco
- La Martinica
In most cases, P. zapotecorum is a slow grower on agar; usually taking around at least 20 days to colonize a 100mm petri dish. In most cases the mycelium turns tan to brown after a few weeks. Some will pigment the agar brown.
It is important to follow the same guidelines of basic mushroom strain selection. Observations have been made that 1 out of around 10 wild clones will fruit in vitro. In most cases wild clones do not fruit well, or at all in controlled conditions with low fae. Although one of the best strains I've seen and tried from Jalisco P Z Elisa is a wild clone and will perform ( not ideally) with low or no fae. That being said it is much more convenient to start from spore. Most spores available are still from wild specimens making it a bit more work. In the near future there will be more stable spores from multiple generations making it easier for the person growing them out.
While a few observations on strain selection are mentioned here, many resources for mushroom strain selection are already in publication that apply to cultivation of P. zapotecorum. For example Growing Gourmet and Medicinals.
All three strains mentioned will pin on agar if left in light at stable temperatures and the media doesn’t dry out. In most cases it’s just a set and forget. This is convenient because Zapotecorum takes a relatively long time to fruit. So running a lot of tests would definitely be more complicated to end up with a viable strain. In the end it’s up to the individual how they want to go about it. As till now observations of pining or fruiting on agar in 3 to 6 months on high nutrient MYA . If in ideal conditions closer to 3. Exact times still to be established. Low nutrients might induce pinning sooner. ( not confirmed)
MYA , PDA , BRF have all shown good growth. Still more research needs to be done. Activated carbon could potentially be a very good ingredient to add to agar and possibly the substrate. Observations have been made of Zapotecorum growing wild in cloud forests in old charcoal pits. ( in contact with clay like forest soil )
Once you have developed or obtained a viable culture you can proceed into the next steps. For this reason, and others, I have come to the conclusion that genetics are one of the most important factors in the success of the cultivator.
Note, sporeless strains, or strains that produce very little spores are common. In most cases it is hard to obtain spores from cultivated Zapotecorum. One reason is, they are hard to grow till maturity, and another is genetic. More research must be done. In either case using swabs is convenient.
ZFC wild clon from Popocatépetl not yet successfully fruited
First agar pin transfer to new media . Then samples were obtained buy new growth.
Classic Zapotecorum mycelium on agar from 3 transfers after first pin clone.
Dikaryon isolated stabilized
Stable Dikaryon consistently producing large pins on MYA
Same agar pin before maturing, Fruit maturing on MYA I believe this particular plate could have had a small amount of some kind of sneaky bacteria. ( possibly having something to do with the large agar fruit ? ) it's hard to know for sure. Although in habitat, in a lot of cases there is a very large amount of soil bacteria and yeasts.
the pin clone got bigger every time, this one even looked like a cubensis.
multiple wild clones from Jalisco being cleaned up and isolate- shout out to Ololiuqui -Damian for taking some clones on his countertop
In almost every case sterilization has been the chosen method, pasteurization has also been used. Bought options work the first is recommended. Even when using soil and sand. It seems to be more about water retention- air and nutrients. Although sterilization is necessary for the wood block method.
It is interesting how contaminant resistant p Zapotecorum are, they will continue to fruit even with molds bacteria and fungus gnats eating the grain spawn out of the wood.
3.0 - Grain Culture
Popcorn was used out of convenience. Many other grains will work as well. Grain preparation is the same basics for all mushrooms.
Fermented Liquid culture broth is of course faster and probably the best option. Standard agar wedge to grain works just fine as well. FLCB recipe in ‘’Growing Gourmets and Medicinals’’ by Paul Stamets.
Colonization was carried out at approximately 75f. Colonization time was around 20 days depending on the method used and inoculation rate. It can be shorter. If using standard agar wedge to grain at least one shake at around 10 days is necessary. They do like being shaked it will speed up colonization.
Sterilized sawdust, wood chips, dowel spawn and or a mix of most wood varieties is a really good option for spawn eliminating the grain completely. Although in some cases it is nice to use high amounts of grain spawn as a supplement.
It can be helpful to add in broth of the final grain and or wood broth to the agar. So there is less leap off time.
Multi spore test on grain. Most commonly observed mycelium type. Note (Popocatépetl strain has growth like this on agar and is a vigorous fruiter)
Wild spore swab directly on grain to test viability. Note the 2 distinct tips of mycelium bottom left more commonly found tomentose. On the top right more rhizomorphic

low teck - A vigorous shake and a little sterile water to disperse the spores. To observe different mycelial growth. Just a test for the viability of germination.
4.0 - Fruiting Substrate
Zapotecorum is very versatile when it comes to choosing substrates. Water retention, nutrition, and strain selection are the most important factors. You can of course, so to say, train or accustom - choose the isolations that adapt best to your substrate of choice or whatever seems most convenient for you.
Bulk substrate of preference would be 50% alder wood chips, 50% alder sawdust. Sterilized just like standard gourmet fruiting blocks. One could even supplement at 10%.
any standard supplement like,bran, gypsum - activated carbon and other npk and basic essential minerals are no doubt beneficial to yield size of fruits and most likely potency.
Cased after colonization, after 60 days.
Pins usually take 16 days after casing and take around 20 to 30 days to mature. If cased immediately after colonización around 20 to 30 days or less depending on inoculation rate and method. The pin set usually takes around 90 days. In ideal casses you could be harvesting in 90 days. In any case It has not been achieved consistently yet.
Casing at 60 days colonization and optimal temperatures around 75 F and around 95% humidity are the only methods found so far to induce pinning a little faster. Much more research must be done. Genetics could be a good way to improve pining time. Strain selection for fast pinning and fruiting strains; as well as more experimentation on environmental conditions. One example is the possibility of flooding or soaking the bags in cold water, something like shiitake blocks.
Since it’s the most easy and local option mesquite chips and sawdust where used instead of alder; many other woods will work. As mentioned in the habitat and distribution section, they are associated with many trees, plants and have a wide range of habitats.
Casing was necessary in the method presented here. With other substrates mentioned, it is not.
Standard casing will work. 40% coco coir powder, 50% vermiculite, 10% dark black potting soil. Another option is to use store bought cactus potting soil that has similar ratios. Trials have been done with pasteurization and sterilization, both options work. Tests were performed with wild spores from Popocatépetl and Eliza Jalisoc wild clone. Just VC also works and probably even just vermiculite.
Jordan Jacobs has had success with a strain obtained from wild spore from Veracruz called La Martinica.
It has been successfully fruited in a modified tub with 50/50 coco coir and vermiculite, spawned with grain. No casing was added except for a small layer of the CV immediately after spawning.
Colonization, pinning and fruit development timings were compared and are just about the same as mentioned. This strain also pins readily on agar and was isolated from an agar fruit-pin.
P. zapotecorum (Eliza strain) Jalisco. Has been fruited on sugar cane by-product sterilized in a grow bag and opened when pins were observed. It also has been fruited on mesquite with casing. This strain reacts and has had around the same timing for colonization, pinning and fruit formation as Popocatépetl. It is a little slower on agar.
note* pining in 45 to 60 days has been observed in a modified tub on either cv or straw-mix substrates from yet another veracruz collection from another friend in the united states mister stabinmecdabin.
Genetics are probably not the only factor for faster pin set. Other methods on P subtropicalis, have been well tested buy a friend in Jamaica and his team. Result in much faster pining for P subtropicalis. I believe these same methods could accelerate the first pin set and flush to a ¼ of the time. Around two weeks. The general concept is once the substrate of choice is colonized it is disrupted and shaken . After shaking and braking it all up it can be cased or layed out in tubs or trays then case immediately. For Zapotecurm this is still in trial method. With high hopes. Considering they like disturbed soils that constantly fall and creat a fluffy mound of highly nutritious substrate and ideal top soil cassing. Also as mentioned above and we all know they like flood areas with well draining soil. To me that indicates they like a high saturation of water. depending on the substrate the soak - shiitake block method, makes sense with a cassing. This could potentially work very well in between flushes. To make sure your substrate dose not dry out. They love water and the mycelium in some cases seems to drink it. In any case p zapotecorum in lower humidity (if not pining or fruiting) – If the humidity does drop, or the substrate seems to dry out in between flushes it must be rehydrated. A mist maker is always convenient

Strain Popocatépetl in a modified tub

Strain Popocatépetl fruited in a small green house
Strain PZE jalisco
Second flush - Popocatépetl fruited in a monotube keeping the sponge-rags wet amd clean
Second flush - Popocatépetl fruited in a small green house with a high mist environment
5.0 - Growth Parameters
Mycelial Types: Finely linear to cottony ; weight with small hints of tan to brownish in color often multi-colored with brownish hues on the mature mycelium. On casing and in less of a degree on grain it will become very rhizomorphic sending up a web like or lightning bolt of mycelium up a grain jar or through the casing. Long strands of rhizomorphic mycelium form and those form hundreds of hyphal knots then fruits and clusters. You will observe this when harvesting in a lot of casses a root like web holding the casing together from the base of a harvested fruit
Spawn media - pop corn - corn - rye - sorghum have been tested with success
Fruiting substrate - mesquite 50% sawdust 50% wood chips
Method of preparation - Stelize bags are inoculated with grain spawn in front of a flow hood or in a glove box then sealed and well shaked
type of casing - cv or cv-soil or sand for best results sterilized it works with pasteurization thin ½” and thicker 1” casing work well
post casing pre pining in bag - substrate temperature 75-81 f
relative humidity 90%
fresh aire exchange 0 per hour
no light
if working with a selected strain that pins with no fae one can place in indirect low light 2 weeks after cassing or when pins are observed. they can be left to mature a little the open the bag to fully mature. In most cases not all the sooner they get aire the thicker they will be. although i believe large thick fruits could potentially be obtained with low fae
Primordia formation- relative humidity 90 to 98 % no les than 85%
air temp 65 to 75 f
co2: 5000 ppm or below
fresh aire exchange around around 2 per hour
light - very indirect low light - highly sensitive to light , pin aborts or fruits turing blue -black and seizing growth may occur with strong or direct light
Cropping - same as primordia formation
Many flushes may be obtained 3 to 4 depending on the substrate if buried in the right fruiting conditions may be prolonged or expanded to more outdoors.
Pg.