Tag Archives: cannabis grow

The Fridgegrow – closed loop growing with co2 support

Weed in a fridge

Flowering cannabis in a fridge
Cannabis that was grown in a fridge using the fridge grow

So when people think about starting to grow weed, they usually look at it from the beneficial side: It would cost less than the shady park vendor or the dispensary in nearly every case, especially when quality is taken into account. The overall quality is more controllable. Plus: In a world with PGRs, terpene spray, brix or artifical cannabinoids its still recommended by me to rather grow at home, than buying stuff simply because the packaging looks shiny.

The fridgegrow controller tries to fill a gap in the homegrow segment. Its not a fullblown all-in-one closet where you have little to no options in terms of light or nutrition, but its also not a tent, where you usually have to deal with environmental values as they come. When the door to the fridge is closed, its not possible to exchange air or even water from inside the fridge. (disclaimer: this is only half-true, but for simplicity we will assume this for that article.) You will have to bring some ingenuity into the operation!

The fridgegrow setup uses a few key elements to keep the environmental values in check:

The fridge

A fridge is able to lower the temperature inside its volume, without exchanging air inside the fridge. Lowering the temperature lowers the possible maximum of moisture the air can hold, water will condense on the cold backwall of the fridge and trickle down…
The fridges total power has to “work” against the grow lights total power, and therefore should be able to “outfreeze” the heat.
The fridge is not included in the system. I recommend to buy a beverage fridge for commercial usage with a closed front. You want to keep the light out. Make sure, that the fridge has as much power as you can get. Its easier to hold the values this way. Heres a fridge from amazon with a clear front, that has to be masked first.

A small heating element

A heater is able to work against the fridge to keep the relative humidity up. In a perfectly dialed in fridgegrow setup the heater will almost never run during the light-on phases, because light and fridge should cancel each other out AND holding onto certain humidity levels while doing so. This is also dependend on the total amount of water inside the fridge chamber.

The perfect light – crescience modular fluXengine LED built

There is no reasoning here for anything else than a high efficient LED setup. No asian amazon light or HPS light will be acceptable if your plan is to grow cannabis in here. Make sure you are able to remove the driver and try to place it outside the fridge. One thing I love about that built is, that I get to chose the light, and its not prebuilt in here!

LED grow light and flowering cannabis in a fridge
Crescience DIY LED setup -3x fluXengine board-style repping the Samsung LM301B chips aswell as a Meanwell – ELG-150-24A

For my fridge I have chosen a modular LED solution by Crescience. Crescience is known for their modularity and compatibilty to standardsized aluminium-framing. Its super-easy to build and you can actually achieve tailored photon-outputs for every system ever.
I am running 3 of their fluxEngines (link goes to the updated lm301h version) powered by a Meanwell ELG-150-24-A Driver.

Some thoughts about the fridge-light-interaction

The principle of continuity says: What goes in has to come out. This is true for everything that has a flow to it. In the case of the fridge one puts energy as heat into the system via the grow light and the heating element. The vapor-compression element on the back of the fridge is able to get heat out of the system and will transport it away through the heatpipes on the back of the fridge. Thats also the reason a fridge is hot in the back and cold inside. Our limiting factor for our light is the fridges compressor efficiency. If our fridge cant transport the heat away through its compressor the inside of the fridge will heat up endlessly, which will result in darkness since the controller will always try to save the plants, no matter if its “daytime” or “nighttime”. This means we need the most efficient and cool running light setup in here. A commercial beverage fridge for business will have a power draw between 90 and 150W from the wall. The light you use should draw a bit less than that.

Air circulation

Small fans directed at the back of the fridge are also an important element in this setup. It keeps the watercycle running smooth and steady. I have chosen Arctic 120mm PC-Fans . I connected them via a 4-way 3-pin fan-connector in parallel and a 12V/2A powersupply. If you are not sure about that, ask an electrician how to wire it.

fans in front of a fridge grow
Arctic PC-Coolers keep the air circulation going in the fridgegrow.

vertical nets or other vertical scrog systems

Keeps your growth in check! I had a few leafs touching the backwall of the fridge keeping the water from dripping down. This results in considerable pieces of ice in there, although its almost 30°C while the lights are on! Ice is bad. It binds water and takes it out of the waterloop.
I gave my plants only 4 glasses of water – in 67 days of growing. And this is a problem.

Scrog in a fridge
Basket-ScrOG system – the grow-space is very limited, so you have to expose as much buds as possible to direct light.

Feeding plants in a closed loop system

While a small windowsill plant doesnt need much to stay green and vital, cannabis under a blasting sun-replacement will transpire significantly more and will therefore have a much increased need of moisture. The trick is to catch the condensing droplets from the back of fridge and guide them back into the pots. Even if youre not able to do that perfectly, the water will still stay in the system, because of the fridges isolation. All you need to do is to close the small hole in the lower back of the fridge, where drops usually get vaporized through the compressor on the back. We dont want that, so we close the loop with a sheet of metal, guiding it back into the pots. This also has disadvantages: Im used to give diluted water-nutrition solution to my plants. Bio Bizz usually is diluted in a way that about 1-5ml of nutritional concentrate gets mixed with one liter of water. This is of course only true for system where the soil can dry out a bit and this wont happen in a fridge setup. You have to put in higher concentration (same amount of nutrition but on a glass of water) or you go for solid nutrition like greenhouse feeding or pre-grow formulas like Biotabs Organics.

I hold my plants in 3 gal smart-pots. Pathological amounts of greenhouse bio bloom and some biobizz was given, but i wasnt really able to conquer the ramping deficiencies my plants developed.

nutrient defincency on cannabis plant in fridge
Leaf discoloration and washed out leaf-tips: this plant was craving for nutrition.

Controlling CO2 – hacking sodamax/sodastream bottles

This is the first setup I was able to make use of extra CO2 inside a grow room. You first need to buy a CO2 bottle, that gets usually used for gassing up beverages mixed together in the kitchen. This bottle is under a standard pressure of about 6 Bar. The first connection has to go to a pressure-bottle adaptor. This adaptor is then connected to a pressure-reducer unit. The reason for that is the next element: its the actual CO2 valve that lets CO2 flow into the system: The CO2-magnet-valve that can be controlled electrical by the fridge-grow controller.

pressure limiter system
CO2 pressure-reducer: left you can see that the bottle-pressure is below 1BAR, so it will have to be replaced soon! On the left is the pressure measured, that lies between the magnetic-valve and the pressure-reducer: theres still CO2 available! But a second bottle would come in handy…

The Fridgegrow-Controller

This is the heart of the system. Its basically a mixture between a server (with a UI to check data and setup the environment ) and a controller. In principle the controller is just turning bluetooth-powerplugs on and off whenever temperature, humidity needs to be dialed in, lights to be turned on and off, or to open and close the CO2 valve. The system is pretty much plug and play and can be setup even if youre not really techsavvy.

fridgegrow controller
The fridgegrow-controller . In the back you can see the droplets of water that will eventually flow back into the soil. On the right-hand-side of the controller is the casing for the temperture and humidity sensor.

The controller will react to different parameters that are more or less dependent on each other. It will find a more or less stable cycle dependent on set values and the amount of water in the system.

Fridge-control

The fridge reacts to two central reading: humidity and temperature. It will turn ON when ever the current humidity rises above the set value AND the temperature is high enough.
In this case that means that the temperature is at its set level or at max. 2x below the set hysteresis. A hystersis-value is the margin a value can go above or beyond.
So if you setup the fridge to hold a temperature between 24°C and 28°C (Thats 26°C with a hysteresis of 2°C) and relative humidity between 65% and 75% (set 70% with a hysteresis of 5%) the fridge will only start running when the humidity exceeds 75% while the fridge is between 22°C and 26°C.
The fridge will turn off when values below 70% relative humidity are reached or the temp drops below 22°C which is 2x the hysteresis. You can see easily that reaching the right relative humidity is dependent on the amount of water in the system. The fridge will never get below certain values if theres too much water to condensate.

Light control

This one seems easy: It just switches on and off at set-times.
But the system is also inhibitng fail-save measurements to save the plant. And heres the tricky part. The fridge can actually overheat while its trying to find a cycle, and thats a nono for the controller. It will turn of any heatsource that exceeds the global temperature limit. And thats the set-tempreature plus 2x the set-hysteresis. So in a running system with a 26°C ± 2°C the light will go out when ever the system breaks the 30°C limit to save the plants.
This can actually happen when theres not enough water around to keep humidity high: the heater will run longer to increase the amount of water in the air and will hit the temp-limit before the humidity levels can be reached. This will perodically lead to on/off cycles of the lights! So be aware of your cycles!

CO2 and Heating

CO2 is kind of entangled from the rest. The gas wont interfere with temperature and humidity and will be dialed in by the controller according to the set value and hysteresis.
The heater is your last bastion to figure out your values/moisture levels in the system. If the controller thinks, that a the heater needs to run WHILE the lights are on you have one of two problems:You need less water in the system!

LESS WATER or MORE LIGHT
The heater only reacts to temperature, so it will only go on, while the temperature drops too low. This can only be the case when the fridge runs too long against the light, trying to reduce the humidity. If you can dial up the light to create more evaporation the fridge will have a harder time reducing the temps, keeping the heater off.
If theres no use to it, and the humidity levels wont fall of with a constantly running fridge and a constantly running light, you have too much water in the system, so try to remove some. But this is basically the equilibium you want to achive: Running heater only when the lights are off, trying to get a stable water-humidity-temp equilibrium going.

The fridgegrow-app

One last word about the fridgegrow-app. To set everything up you need to be connected to the controller via the app or the controllers local webiste. If you dont connect the controller to your local wifi (which i recommend for safety concerns) you have to use the internal wifi from the controller. The controller guides you through the first setup of the remote-power plugs and is pretty easy to use with a standard UI and graphs of the sensor-data. Perfect for a nerd-grower like I am! In the graphic below you can see that i turned on three graphs, temp, hum and CO2. In the graphic you can see the exact moment when I opened the fridge at 19:15 or 7:15pm. the humidity and CO2 drops significantly as I pulled everything out of it, when I opened the door. The CO2 controller will turn on immediatly while you can also see the heating element tries to work against the fridge to keep the temp low.

screenshot of fridgegrow app
View through the fridgegrow app – setup your controller, check your values – remotely

Wrap-up: Should you buy a fridge grow?

For the beginners: Yes, its possible to just watch and learn with this system. Its really an accomplishment and a good amount of work to have it running stable for the first time, but you will be given a system were you have full control of every aspect of a run, while still be able to hold smell and noise in place.

Its for the nerd who grew weed in the past, but maybe dont want to have the whole fan/tent etc. infrastructure in his family home anymore. Maybe you want to get most of a limited space? This system got you definetly covered. I will try to harvest 100g dry regurlary out of there, and this should be enought to supply a single consumer out there and I am convinced that this system is working since I got my first 60g of Humboldt Seeds OGKZ out of there and it was a more than decent smoking experience. Welcome to the 21 century growers!

The Farm – Perpetual cannabis growing at home

If you are growing at home for you personal use, you most likely own a single tent, a light (or two if you swap between veg and flower), some pots, soil etc. A single grow can be seperated into five different stages (0-4), and all of these stages take place inside that single tent. What if you manage to give every stage its own small room? This is called a perpetual grow. You swap tents respective to the stage your plant is currently in. Maximize your space and grow more efficiently.

View of a room with tents
I filled about half a room of my apartment with the tents and equipment.

Stage Zero: Cloning – The Greenhouse

For rooting cuts have a small greenhouse on the side. In this stage plants do not need ungodly amounts of light. I shine a small photolight or a desklight on them, to keep the clones from flowering. The rest of time I wait until I see roots emerging from the side and keep them moist. Not every new plant undergoes this stage, but seedlings can also be kept here if needed. Its also perfectly fine to put the greenhouse into a tent, if it has sufficient size.

indoor greenhouse with cloned plants
Some clones in a VERY DIRTY greenhouse thats really not suitable to show off online. Shame on me.

Stage One: Clones, mothers, early veg – The Living Collection

The real first step into perpertual growing is seperating veg and flower. My clone tent happens to be a 2×2 tent for me with a cheap blurple light to keep things alive. In this tent I let my clones root through their pots and keep mother plants. Not much is happening here. Keeping everything green and vital is hard enough. The lights are on 18 hours a day.

blurple light in a tent with clones and mothers
The collection: This tent is always a bit chaotic. Everything that has to be kept alive is in here.

Stage Two: Vegetative tent – The Gym

Here it gets interesting: This is also a 2×2 tent, but with a much better light. I am using my Lien-Tec Dual Quantum Cube in here to get the plants used to the amount they will receive in the flowering tent. I also repot them into a 20l (5gal) pot, once they filled out their initial pot and let them root through. In this tent most of the plant manipulation takes place. The plants will be in here for about 4-6 weeks until they move on into the flowering tent. They get topped and LSTd, pruned and schwazzed in here, whatever you feel like doing to them.
My personal strategy: Get them to fill out their respective space twice, then cut away all but a single node on top of every branch three days prior to the flowering period and swap over new plants from the Stage-One-Tent.

veg tent with vegging plants
Vegging plants in different stages. While the plants in the back are getting ready for flowering, the ones in the front just got transplanted.

Stage Three: Flowering – The Sunhouse

Where the magic happens: Every plant going in here is fully vegged, trained and ready to go. No timeloss here, everything is running at a 12 hour light cycle forever – no darkness periods or whatsoever. The plants in here most get spread abit with gardening wires or hooks. They also get the day 21 and day 42 defoliation and of course: water. But thats also basically it. Keep the tent clean! You will not have off-periods after a harvest to do that. So once a month, take everything out, get your antibacterials in here and clean your garden.

My current flowering tent runs on 6x CXB 3950 Cree COBs condensed into 2x Pro Emit Sunbars 150-B and 2x HLG QB288 V2. Totalling about 570W this tent is packed with light.

flowering tent with plants, lights and a fan
The beginning of a perpetual grow: Emptyness in the flowering tent. The number of plants will rise with time.

Stage Four: Drying – The Barn

This is more or less a small darkroom where 3-4 plants should fit in, drying. You are used to hang every thing from a tent inside said tent for the initial drying period. This is a huge off-time where your tent is blocked for veg/flowering purposes! My small IKEA-hack (article is pending…) involves a kitchen cabinet with wheels and a big hole on top to connect to one of the tents. This way you get a suction airflow, thats perfect for drying bud initially. The room does not have to be as big, since you only harvest 2-3 plants at once using that method. To dial everything in, you will need about 3-4 month of planning. In the first iteration you can even stat mulitple plants in each of the stages and cumulate them after a while in the flowering tent. This is your last step to perpetual grow: get drying out of the flowering area.

Useful tricks

Plan ahead

So with one single tent you have plenty of time to choose new genetics. In this operation you have to choose genetics about every two weeks, so be prepared! Work out a plan for several month ahead and stick to it. You will learn how the system dials in, and how long each plant can veg etc…

picture of a calendar
You can print out sheets of these calendar-pages to keep track of every plant. You can find them here.

Maintain a journal of everything

Once you gro perpetual, you will handle much more plants in every possible stage at once. They all have different needs. Keep track in what stage every plant is at the moment. Write down things like date of germination, date of switching stages, how many days they were in each stage, etc. Keep track!

Have fun!

With this perpetual grow method you should be able to not only keep more genetics in your operation but also have a steady refill of your stash instead of a massive haul every 3rd to 4th months.

The Pro grows: El Patron by Royal Queen Seeds

El Patrin main bud close up
This is what you get – El Patron main bud by Royal Queen Seeds, grown by Homegrow Pro.

Back to square one – from a Royal Queen Seeds veteran

Growing El Patron felt like I was going back in time. Royal Queen Seeds was the first breeder I bought seeds from – Amnesia Haze Automatics being the first. And also the feeling not really to know what I’m doing wrong was there again.

One year after my last run with RQS Critical – my last RQS run until El Patron – I have now a lot more experience under my belt and equipment in the closet.

Items and Tools that I used for that grow

The Grow Room – Setting up

I had the opportunity to test out Lien-Tecs very own interpretation of a Samsung Lm301b chipboard including the now commonly used photo- as well as far-red LED chips on a passively cooled fixture. The system came with an LCD display with a dimmer attached to set the power as desired. In the 2’x2’ (60 cm x 60 cm) tent area I dimmed the light down to values between 120 W (seedling, veg) and 160 W (early and mid flower).

Lientec LED screen to setup the power of the led and monitor current and voltage
Lien-Tec LED: This model features a very convenient screen and power adjuster!


For air circulation I used one low powered static fan inside the tent and an AC Infinity Cloudline T6 for filtering and air-exchange. I aimed to grow four plants total in 3 gal smart pots filled with my go to soil: BioBizz Light Mix. Not too hard on the seedlings and cool for the first weeks alone, while also (usually) easy to maintain when combined with the BioBizz nutrition line, which I also did.

Seedling and Vegetation Stage

small seedling coming out of the soil
El Patron – cracking the soils surface

El Patron had a rough summer to germinate in. I got my four favorites and started the run, at first separated under two different grow lights, but altogether after a brief time of three weeks.

Right after germination I recognized the first problems: All four plants seem to “forgot” to develop one of the second-set branches, resulting in a weird triangle shape. Cannabis plants usually retain a decent symmetry for a longer time after sprouting – especially under LED lights. Followed by the first signs of nutritional malady they grew okay in veg. Longer internodial distances and a vague signs of nitrogen deficiencies were always visible. “I had it worse…” – I thought and wanted to let them go vital before switching to flower.

small cannabis plant with a weird shape
El Patrons shape is very unique (or weird) in the first weeks of the grow. All four plants showed this feature.

For training I’ve chosen my favourite LST method with the metal hooks you can read about on my website here.

Flowering

flowering cannabis
In the tent: El Patron does not like to stretch a lot, flowering was uniform and easy to manage in terms of stretching and structure.

I switched to flower rising the power usage of the light to 160 W from the wall, while I reduced the hours of light per day to 12 hours. I also raised usage of the nitrogen source in order to get ready for the flowering stretch. Up to three weeks into 12/12 the plant is still creating large amounts of green material such as branches and sun leafs and grows exponentially, raising its height by up to 300%!  In the same time I increased usage of the potassium (K) and phosphorus (P) parts of my nutrition plan and let it buffer up in the soil to be ready to use mid flower, where a plant is the hungriest.

Cannabis mid flowering
El Patron in mid flower: Shes stacking up nicely but always showed a bunch of nutrition problems. Maybe the pH was off….

El Patron is a late stacker. You have to wait to the very end until she abruptly stops pushing out bud volume. I was greeted with medium to medium-high yields of bud. Was the quality worth all the hassle?

cannabis ready to harvest
El Patron short before harvest: The leafs are dry and curled upwards. This picture was taken 18 days after the one above.

The Product – taste, potency, flavor and smell

To answer that question: For me, definetly. I am a taste/personal use grower, so yield is not the first aspect when it comes to growing. I want new tastes, flavors, structures, views and colors. While the colors were nothing special in this run (although I tried – running sub 20°C in the nights) the initial smell is mesmerizing. The first thing I thought was: ”Oh, it’s just like Lemon Haze! “, which is very commonly the first distinct terpene variety you experience as a rookie cannabis consumer. If you squeeze it you get whiffs of cookies and cream as well as parsnips, without being too dominant. Smoking it reminds me of oldschool Amnesia taste, also no surpise due to the AMG lineage.

This strain is covered in trichomes! So frosty – its unreal!

The high drops in hard and head-heavy: I got talky as usual and was in urgent need to eat a lot of food in a short time. I also got pretty much useless doing tasks that involve a lot of different steps at the same time, so I went and did another round of macro shots of the now dried out plant. The buds were exceptionally dense (apart from that one pheno that didn’t) and became rock-hard in the initial drying phase. There will be some remoisturization going on, burping and curing her, but at a first inspection – very grindable and enjoyable material! Should also be very good for extracts like hash or rosin.

If you are a hazelover who needs head-high in the afternoon to clean up the living room (very slowly!) – here you go! El Patron by Royal Queen Seeds – Thanks again for the opportunity to grow a new variety. Its a great experiment to set “new grounds” for a new strain!

Trichome closeup: There is also plant material in this picture – believe it, or not.

DIY 130 W LED light Feat. The crescience FLUxEngine

Video with build instructions

This article will cover how to build a solderless LED light thats scalable and very easy to set up. Check out why LEDs are superior.

The build shown here is beginner friendly. You dont have to drill into metal and the boards do not need active or passive cooling, since the framing will be sufficient to do that. If youre more into COBs, check out my 310W COB growlight guide!

This article will cover how to build a solderless LED light thats scalable and very easy to set up. Read more about how LEDs are superior.

Disclaimer: This piece of electronic is a potential fire hazard and should only be put together by electricians or persons with similar know-how. Please refrain from putting in self-made electronics into the wallplug. Dont die!

Itemlist

For this build you can either buy the whole kit from the LED builders website, or you look for a bunch of groove profiles from metal dealer thats suitable for you. Mind that I cant give an amazon link for that, since the orders are most likely to be custom made.

Groove Profile – use these, so you dont have to drill into metal!

I used 30 cm and 38 cm long profiles with a 4cmx4cm crosssection, so you can build a square-shape out of it.

You also need a bunch of metal sliders. Make sure, that the sliders fit the profiles.

Metal sliders that are needed as holes for the screws.

Every slider needs a fitting screw aswell. To connect the framepieces You will also need some angles. There has to be one on the side where you will buy the framing that fits the profile. It should look somewhat like that:

Angle connector for the frame.

For this particular build I used 4 FLUXengines to achieve a total power of 130 W for the 2×2 tent its used in. Be aware, that these boards might require screws with a smaller head, so you dont drill onto the LED modules.

FLUXengine with the power connector in the front and the Samsung lm301b chips on board.

The ELG-150-24A driver is the connection between the wallplug and the boards. You will need one of these. The boards are connected in parallel.

The driver!

You will also need about 50 cm to 1 m of single core copper cables to connect every board with the driver. I suggest you buy two different colors: one for plus, and one for minus. The cross-section of the wire should be between 0.14 mm² and 0.5 mm². Mind that once you used 0.5mm² cables on the connectors, you will not be able to switcht to the smaller ones.

Single core copper cables are easy to clamp!

For further connections and cable collection you will also need to buy WAGO clamps. Two 5-way clamps to connect all the boards in parallel to the driver, and three 2-ways to connect the driver to plug cable for the wall.

Wago Clamps for cable connection.

Last but not least its important to hang the lights from the top of the tent. Get four hook screws in order to do that.

Use these to hang your light!

Take some measurements first

Lay down your frames in front of you and put the boards on top in a symmetrical way. After that you estimate the cable lengths and cut them. Strip the isolation and connect the cables color-coded to + and to the boards and guide them throught the aluminum profiles. Its better to take longer cut here, hust to be save.

After that you take your metal sliders and also guide them through the profiles. You can now screw the boards tightly to the to the frames, and the framepieces to each other. Before you screw together the frame pieces, make sure to have all sliders in the back installed aswell. You wont be able to access the shorter parts anymore or you have to unscrew everything…

Connecting the cables

The schematic shows how its done. Collect all minus and plus cables together and put them into a 5-way WAGO clamp each. The voltage delivered by the driver stays constant while the current gets forced to a maximum output of about 6.3 A.

All cables are connected, the light is hanging safely – time to grow!

Testing and mounting

Four Crescience FLUXengine modules haning in the tent

When everything is connected nice and tight, you can now plug it in and look if it runs. Dont look directly into the light.

Done! This light should draw around 130 W at the wall and is able to light up a 60cm x 60cm grow tent (2’x2′).

Scale up!

The four modules can also be connected to a bigger drivers. Each module is able to put out 60W of light, so if you have the ability to hold down temps, you can also use ELG 240-42 running at 5710 mA to reach about 230 W with this setup. Mind that these chips run hotter and less efficient in this configuration, but will still crush any blurple or HPS lights in comparison.

Topping

Topping is an invasive training method. Contrary to Low Stress Training a plant needs a significantly longer recovery time from an amputation, which sounds reasonable.

Timelapse of a topped cannabis plant

As you can see, the plant is developing more than one main branch. This happens due to the amputation.

The right moment to top – mainline or spreading

How to top cannabis plants
The topped plant has already established very noticable side nodes. These will be the new main Branches

The right moment to cut of the head of a young cannabis plant is to choose carefully. What to you want to achieve? If you want to spread out her sideshoots you can wait until two weeks before flowering to cut off the main. The plant will distribute more energy and growth into the sidebranches which will develop much better after that. So you end up with more thicker branches at even height which will also optimize growth overall. Growers who do that, like to top a bit later into the vegstate (after the 5th node) and refrain from low stress training in the way to let the shoots go upwards.

Example of a topped autoflowering plant
Autoflower that got topped without mainline. source

Mainlining your plant has a different approach: Its more of an artform and maintops will be developed in a more symmetrical manner. The topping has to happen much earlier in is my favourite approach to HST or high intensity stress training. It combines HST with LST very early on in the life cycle and gives you the ability to guide the growth of the plant in a more detailed fashion. It also let the plant stay small and bonsaiesque which is favorable for small grow spaces with low heights.

Mainline branches
Plant that got topped and put under LST at least twice. This results in 2^2=4 shoots.

Mainlined plants are split up immediatly with next to no internodial growth. That results in a distinct number of tops: If you cut away the mainshoot n times you will end up with 2^n mains.

triple mainline
A plant that got topped a third time, resulting in 8 main shoots.

Pros and Cons of topping

First of all topping costs time. Flowers need to heal up of that for about two weeks before you can think of switchting them to flower and establish a healthy branch structure again. You will end up with a more even canopy, can bring the light lower and will ultimately get more yield since more buds are in close proximity to the light source. Mainlining takes even more time than just a single top, but you will be able to shape your plant in various ways because all fresh branches are still young and flexible.

My recommendation: Take your time and let her veg for 2-4 weeks longer. You wont be disappointed in the end.

Topping Autoflowers

Yes, topping autoflowers is definetly possible. The best strains to try this in are the ones with a longer life cycle like most sativa dominant strains. The moment of the amputation has to be crucially timed tho. If you think the plant is already about to strech or shows early signs of sex, you should refrain from it. The time window to properly top an auto is pretty thin. Be careful here. But as I said: Its worth it in the end.

A mighty cannabis flower
If done right you will end up with a massive canopy of donkey dicks! (This is not an autoflower.)

The Pro Grows: Lemon Zkittle by Dutch Passion

Why you should grow Lemon Zkittle

With the on-going legalization in the US and Canada many awesome crosses have emerged from the vast number of varieties developed in that part of the world. Next to OG Kush, Cookies or modern strains like all the Gelatos there is one name to be heard all the time: Zkittlez.

Lemon Zkittle by Dutch Passion is a derivate from Las Vegas Lemon Skunk and cupwinning Zkittlez relative. Her THC content exceeds the 20% as all modern strains seem to do. The phenotype I have grown shows some differences to the given description by Dutch Passion due to the conditions she was in. I grew her in winter, so at lights-off the ambient temp in the tent could drop somewhat under 20°C which gave her a little purple shade in the end. I also used prefertilized soil by Kanamu Pacha and solid nutrition in the form of the GreenHouse Feeding Bio Line. So no bottled nutes were used this time, only organic material that has to interact with the medium and water.
The resin production of the Strain is outstanding, and you will end up with a carpet of trichomes on the leaves and flowers.

Mature cannabis plant
Lemon Zkittle seven days before harvest showing amazing resin production.

Items and Tools

TL;DR – Lemon Zkittle

  • Strain: Lemon Zkittle by Dutch Passion
  • From seed to weed: 143 days (veg 76 days, flower 67 days)
  • Wet harvest weight (wet trimmed): n.a.
  • Final dry yield: 188 gr (6.6 oz)
  • Effect: extreme strong, head heavy, paranoid, numb/dry mouth, long lasting
  • Taste: Due to some fuckups by me on the hay side, subtly lemony, next to no Zkittles flavor

Grow it…
…if you like US resin coated sugar strains.
…if you like lemon flavours.

Don’t grow it…
…if you like to mainline your plants.

The Grow

Germination and seedling stage

I used my usual method to germinate two seeds in a paper towel. I used pH-regulated water (pH of 5.7 to 6.0) and let it soak in water until saturation.

items for germination
Items im using for germination: Bowl with water, paper towel, seeds (in the middle), a jamglass lid, pH-meter
seeds on a papertowel
Put the seeds on the paper…
wet papertowel in a jar lid
Let the paper soak in water as much as it can, and add some additional water to the lid.

This way, the seeds start with a lot of moisture. Put the ghetto-petri dish in a warm (around 27°C is perfect, but not necessary) and dark place and check it every 24 – 48 hrs. After 3-7 days the seed should be ready to pot when the inital root is between 0.5 cm and 1 cm long. The soil should be at least a bit moist at this point, but not dripping wet. Make the root look for the moisture and stretch to it. Place it about 1.5 cm deep and put some loose soil above it.

cannabis seedling in soil
Lemon Zkittle Seedling looking through the soil.

After a couple of days the seedling should break through the soil. In this stage the seedling is most vulnerable. I recommend to just let it be, and keep the area around the plant moist. I use a water sprayer for that. In this time I wet the soil every day. The stem and roots are not strong enough to keep the plant standing if the soil is too wet, so prevent that. Its not lethal if it happens tho. After some days the stem will be strong enough to use my flood watering method again. Since the roots need time to grow through the soil, you can take 5l of waters for the 30l of soil and you will need to water only once a week for starters.

Vegetative Stage: Training!

14 days after germination the plant was ready for the first top at the forth node. I wanted to achieve a mainline of four branches going in perpendicular direction and keep the secondary branches coming out of them for a massive bush.

topped cannabis plant
Cut of the main top of the plant on day 14 after gemination.

The mainline was done via the metal stakes im using for a while now. The branches keep growing horitontally while second nodes develop more heavy since the plant wants to compensate for the hassle of the main branches. I will never

LST applied on cannabis plant
3 days after the top, the plant was ready for LST.
LST reaction from the plant
Lemon Zkittles reaction to LST

The LST is applied everytime the plant grows back pointing upwards. This can take a lot of time, since i wanted to fill up as much area as possible.

reaction of the plant due to LST
A new round of LST is applied (left). After only three days the plant is ready for the next round.

This method will result in a great amount of nodes and leaves. Its your job to decide which node you keep and which one to cut away. Usually I keep mine for a week or two to determine if the plant is distributing energy to it. This will be adressed later when it comes to lollypopping in flowering.

bonsai cannabis
LST keeps the plant flat in check.
LST and clear bottom of plant
Keep the lower branches clear, to reduce larf/popcorn growth in the flowering stage.
stalk of cannabis plant
The stem will grow to a big stalk the longer you veg, and the more room there is for the roots.

Flowering Stage

When the plant uses up most of the grow area its time to send her to the flowering stage. Note that this is only possible if you are using regular or feminized plants and not autoflowering ones.

cannabis plant in full scale
Lemon Zkittle in early flowering filling up the space.

This plant was in veg-stage for 51 days before flowering. In the first 21 days of flowering I let her stretch out and removed some leaves here and there, but nothing major.

stretching plant
Stretch of the Lemon Zkittle is pretty moderate. The mainlined tops are clearly outstanding in height.

On day 21 I removed a lot of fan leafs and cut away some poorly developed tops. The reason for this is, that I want to have well developed main tops instead of a massive amount of larf. From that point on there will still be a fan leaf found casting a shadow over a bud once in a while. Rule for removing leafs: If a leaf keeps direct light away from a bud, it has to go.

Rule for removing entire tops: If its way below canopy level and poorly developed, it has to go. Disclaimer: I should have cut more on that plant. The plant has about 50-60 tops in the end, and the pot was way too little to distribute energy to every single one of them properly.

cannabis in early flowering
Bud development on the numerous tops I left for flowering.

After day 21 i basically just sit and watch the plant thrive. Keep her fed and watered and watch out for deficiencies. This plant was grown fully organically and i stopped actively giving nutrition around week 5 of 9.

cannabis maturing in flowering
Trichomes are highly reflective and look very frosty in the middle of the grow.
single cola of cannabis plant
Lemon Zkittle cola in flowering. This structure with no space in between buds is a very desireable property.

In the course of the grow the Lemon Zkittle developes an amazing trichome density. This is always a good sign! The trichomes start with clear appearence.

macro shot of cannabis plant
Macroshot in the middle of flowering. The trichome denisty is top notch. The trichomes are mostly clear and the pistils are pointing upwards. Maturity is still far from reached.

After seven weeks, the plant shows visible signs of deficiency. Since the life cycle would be over after week 9 to 10 and im using organic nutrition I refrained to use more of that on her and let her fade.

full scale flowering plant
Late flowering: The leaves turn yellow
macro shot of trichomes
Mature flower: The trichome start to change from cloudy to amber. Its time!

After 8 weeks the trichomes were mostly cloud, while a good portion already started the transition to amber. I had her in the closet for another week and harvested her on point after 63 days of flowering.

Harvest and curing

Harvesting such a large plant is not always easy. She had such a large number of tops that I had to do the whole ordeal in two days. I let her dry off about 10 days as a whole plant before I went to dry trim and curing. I aimed for 300+ gramm but only came out about 60% of that. Thats fine for a single plant, but I think I screwd up the training process and was a bit less patient for the flowering switch to happen. I cured her for about a week with burping and paying close attention to the feel of the product. After that I used the C-Vault and Boveda Packs to further store the goods in a perfect environtment. In the end I would like to encourage you to tryout that strain. The trichome density and frost of the flower is extreme and the effect is equivalent to this.

Cheers.

Defoliation – Make way for the light

Buds tent to develop best, when hit by direct light. If a bud is overshadowed by big green fan leafs the bud will develop not as good. Defoliation is the key to make the most of your plant and maximize flower development.
This grow tech requires a bit of experience and knowledge of a Cannabis plants structure. I do not recommend this if this is your first grow. After a full run, without removing leafs you will know exactly what to look out for the next time.

There are growers out there removing nearly every fan leaf that a plant grows after 21 days and after 42 days of flowering. This is called schwazzing and a rather extreme manipulation technique. The other extreme is to remove nothing. My way of defoliation will remove a lot of leafs in the process, but will leave a lot of leafs for the plant. Its kind of a middle way.

The Pros way: Moderate or selective Defoliation

Not every plant needs to be defoliated the same amount. There also no godly plan to defoliation for all the plants.

Defoliation in the vegetative state

If you have a very bushy indica dominant strain or applied a lot of LST to your plant it will potentially grow very bushy. In extreme scenarios only a few leafs on the top of the plant will be necessary to build up a full canopy.
This is not good if you want to encourage branches under there to develop!
Remove the big fan leafs from the top of the plant to make sure that budsites below get direct light aswell.

freshly defoliated plant
Freshly cut plant: Fan leafs from the top of the plant got removed
recovered from defoliation, new growth is visible
New growth after three days: The gaps have been closed by new branches taking the spot.

How to check if a certain fan leaf should be removed:

  • If the fan leaf creating a shadow to budsites below remove it.
  • If the fan leaf is growing “inwards” or growing bigger and bigger, remove it.
  • If the fan leaf grows at the edge from the plant away, it can stay.

This way you will remove the leafs very selectively and keep the plant not as stressed out. Its also not feasable to potentially stun the plant because you removed so much.

Defoliation in the vegetative stage can be tedious since it could be applied about every third day from a certain plant size on.

Defoliation in the flowering process

This is pretty similar to the vegetative state. Since the plant will still grow new green material, remove the leafs that steal light from buds. Just look closely at every bud and check if there is a leaf above. Remove all the leafs. From about week 3-5 the green development of the plant will be reduced because the plant packs more supply into the flowers. Your work is pretty much done then regarding defoliation.

Extreme Defoliation: Schwazzing

Widely in use by certain industrial grow operation schwazzing is the process of removing nearly every fan leaf that grow on a plant at the beginning of the flowering stage, leaving only the top of every budsite intact. This method also involves some kind of lollypopping since every side branch is pretty much removed as well. Just leave the first 2 to 3 nodes from every branch intact.

Timelapse video of schwazzing in an industrial grow setup. These operation have a lot more light power per squaremeter than a common homegrow. The lights can penetrate much deeper! Schwazzing a plant makes sense here.

Chocolope that got alot of nodes removed, leaving up only the top of the plants, sortly before flowering.
The same plant in flowering: Branches full of buds!

Additional notes

I would not recommend schwazzing for every strain out there. There are alot of cannabis varieties that are able to put on serious weight on the side branches where you would harm more than you do good if you remove too much. Branchy indica type plants are very much content with selective defoliation while some other plants like to be cut more heavily. I suggest you.

Lemon Zkittle that got exposed to defoliation: You can see through the branching to the other side of the pot.
Alot of Budsites are directly visible from the topview, since the light now got a free way down there.
Areas that wont get direct light will be cut most.

Defoliation is a pretty harmless tech, since a plant will develop way more fan leafs than needed to survive. A grow tent is also an environment where the plant is enclosed and save enough so that it can deal with this harm without having to fight pests or difficult weather patterns while at it.