Increased Cannabis Yields – When To Harvest Part 3

Would you like a surefire way for increased cannabis yields? Harvesting at the right time can result in increased potency and even a 20% yield increase. So how do you know when to harvest?

Harvesting For Increased Cannabis Yields – Here’s The Worst Way!

The absolute worst way to harvest your weed is going by the breeders days to harvest! Remember breeders want to sell seeds so they tend to give earliest days to harvest possible. Now the weed may be OK to harvest but that doesn’t mean it will provide the best yield.

Even if they are not trying to mislead anyone every grow is different because every grow room is different. Lighting is different and temperatures and humidity vary. This has a profound effect on when a crop is actually ready to harvest.

When To Harvest For Maximum Yield

You can follow this grow at: https://420grower.org/death-bubba-grow-journal/

When Should You Harvest Your Weed?

Everyone looks forward to harvest. But we often take our plants too early because of the anticipation and excitement. In doing so yield and potency are often sacrificed. So how do we avoid this? The three most common ways we measure maturity are by brown hairs, trichomes and fading.

Brown Hairs

Harvesting when the hairs turn brown is most likely to cause a loss in yield. It is not a reliable way to determine maturity because buds continue to grow and swell even after the hairs are brown.

Checking Trichomes

Checking trichomes is a better way to gauge maturity but it’s not perfect either. You are only looking at the outer layer of trichomes and not the ones in the bud itself. You will notice top buds matured and bottom ones needing more time with this method. Also some strains do not make amber trichomes and they can be harder to see and % amber is really just a guess.

Waiting For The Fade

Fading is one of the best ways to determine maturity. Hairs should be brown and trichomes turning at this point so really no need to check them. You want a complete fade. If the top leaves are turning and the lowers are still green they are not ready. Sorry.

Some people will tell you that all plants will not fade. These are usually the impatient ones. All plants will fade when they are done. If you over fed them it will obviously take longer to get everything out.

The importance of a good flush that removes all nutrients from the pot can not be overstated. But there are still 2 to 3 weeks of nutrients inside the plant that the growing buds will use up.

So you really should start to flush while the plants still have some white hairs and are actively growing. With nothing for the roots to take up the plants will draw on the stored reserves in the leaves. This is how to get a complete fade and know your plants are done.

The Easy Way To Increased Cannabis Yields

If all this seems to complicated here is the simplest and easiest way to increase your yield: Wait until you think your plants are done. Then wait another week before you harvest them! Trust me, you will get more bud and higher potency.

SUB IRRIGATED PLANTER BED INVITE

I would like to invite my subscribers and anyone interested to check out my new YouTube channel Sub Irrigated Planter and new website http://subirrigatedplanter.com

To say I have been really impressed with how well my recirculating SIP system is working would be an understatement! Frankly I did not expect this!

I have grown in many systems including: aeroponics, flood and drain, top feed drip and even hand watering. Nothing is as simple or effective at watering than a SIP. When I first tried it I thought it would work or I would not have tried it in the first place. But I thought something this simple would have severe limitations and I love to prove myself wrong LOL!

I want to share it with everyone whether they grow cannabis or are just a gardener growing veggies.

End Over Or Under Watering With A Sub Irrigated Planter Bed

Did you know over watering is a huge problem? It can ruin many crops just as quick as under watering. The problem is the symptoms are much less obvious. So while a plant may look OK its roots can be suffocating from lack of oxygen. Over watering can cause nutrient lock outs and sometimes the symptoms even look like under watering.

By using capillary action plants take up or wick water as they need it just like how a plant grows in nature.

Here is a recent article on this site explaining what a sub irrigated planter bed or SIP is and how to make one https://420grower.org/diy-sip-grow-system-for-cannabis/

So I am still 420 Grower and I am not abandoning my channel or other websites. I just felt this method deserves more exposure especially with home gardeners. So I am broadening my horizons a bit.

Thank you all for your support!

MORE INFO AT:
http://subirrigatedplanter.com/

ON YOUTUBE:
https://www.youtube.com/channel/UClQ3kokj6CzBH4uUXB5VPlg?

DIY SIP Grow System For Cannabis

Check out my DIY SIP grow system for cannabis. SIP stands for sub irrigated planter and it can grow just about anything but cannabis is my favorite plant so here goes!

First let me say I did not invent this. It came out of reading about and watching videos about diy self watering planter beds. Most of them were about growing vegetables and I adapted it to growing cannabis in smart pots.

The SIP growing system is a great way to water because it eliminates over or under watering. One of the biggest problems many growers face is getting watering right. If plants dont get enough they can shrivel and die. If they get too much the roots dont get enough oxygen and plants are stunted.

So how about trying an easy to build sub irrigated planter that gets watering right each and every time?

Not only is it a really easy DIY project but it is also inexpensive to set up. These diy self watering planter beds can easily be automated if you want to. But they can also be run totally passive with no pumps or electricity needed.

My DIY SIP Grow System

In the video below I show my system at work. It is a bit more complex and not passive but it is giving great results. The great thing is even if it were totally passive it would still give the same great results.

How To Set Up A SIP Growing System

Have you ever cleaned up a spill with a paper towel? Then you know it wicks and soaks up water by capillary action. Water is pulled into the napkin and this is the principle that makes a SIP work.

Capillary action (sometimes capillarity, capillary motion, capillary effect, or wicking) is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to, external forces like gravity.https://en.wikipedia.org/wiki/Capillary_action

Water moves from a wet medium and is wicked up by the bottom of a smart pot. You dont even need to understand how it works because it just does it.

There are just 2 things to keep in mind building a SIP. First you need a porous medium like hydroton or perlite. River rocks, gravel or pebbles wont wick well so dont use them. Besides they are really heavy.

Second your smart pot needs to be above water or your plants will drown. It will all make sense once I explain how to build one.

What You Need For Your DIY Sub Irrigated Planter

You will need a container. It can be a tote, cat litter box or mixing tote like the ones I use in the video. It needs to be deep enough to add a layer of grow media for your wicking bed. And it needs to be water tight because we are going to fill it part way up the medium with water.

Get yourself a smart pot and medium to fill it with. 2 or 3 gallon smart pots will grow big plants when filled with coco or a coco mix and there is no need for anything larger unless you are really growing trees. You can use straight coco or you can mix it with some perlite. You dont want to use anything like garden soil because it is too heavy and will compact when watered.

Sub Irrigated Planters Are Simple! Dont Overthink it!

That is all you need to build a basic SIP that is hand watered! You probably will want to add some automation so you are not always hand watering. This can be from a gravity fed reservoir and float valve or a flood and drain type system like I am using.

Here is a good starter thread I found online: https://forum.grasscity.com/threads/noobwannbs-self-wicking-smartpot-ghetto-setup.1151159/

DIY Recirculating Smart Pot SIP System

Most Sip systems I have seen are hand watered or at best fed through a reservoir with a float valve. Also most of the systems I have seen use organically amended soil of some type and generally are not fertilized beyond that.

The most common systems seem to be made with double buckets and use a cup for a wick. A few growers started experimenting with smart pots and I really feel this is the way to go.

Why A Smart Pot SIP System And Why Recirculate?

Smart pots naturally wick moisture and they can breathe. They also root prune and yield more than a similarly sized hard plastic pot or bucket. They are the ideal container for a SIP system.

Since I am an old hydro guy the idea of still water scares me. I want my water to be moving and I also want my water to supply nutrients. Moving water carries oxygen while still water is anaerobic and stagnant water carries a risk of pythium and other diseases.

Roots are going to eventually make it out the bottom of the smart pot. Since it is not laying on a hard surface there wont be much root pruning. Roots sitting in stagnant water is unhealthy and never a good thing. This is probably the best and most important reason to recirculate your nutrients.

Flood And Drain SIP?

If you watched the video above you can see that I have built a recirculating SIP system and that I am using 3 gallon smart pots. I used 20 gallon mixing totes that I bought at Home Depot for about $13 each. They are about 2′ x 3′ and I used 3 in my system. There are 2 for my plants and the third is placed below them as a reservoir.

Some Recirculating SIP Pictures

The planter totes have been fitted with ebb and flow fittings. This system can be used quite readily on flood and drain tables but since it runs continually there is no ebb and flow.

I use the 3/4″ fitting for a drain and the 1/2″ to fill the totes. Inside the reservoir I have a 400 gph Ecoplus pump which cost around $25. I installed the included 1/2  output fitting with a short piece of tubing that went to a tee and connected the tee to 2 short pieces of tubing that connect to the flood fittings.

If you are only running one tub it is much simpler to hook up of course.

Make sure you get the with the screw in plastic screens.

One screen keeps the water from spraying all over and the other will keep the perlite or hydroton you will be using out of your reservoir.

I allow my drain to fall into the reservoir below to add some aeration but if you dont like the sound of water running you can put some tubing from the end of the fitting into the reservoir. Personally I find the sound very relaxing.

You want the totes to be on a level surface so water will spread throughout the tote and you dont have any high or low spots that could result in uneven watering. After you run the pump and make sure everything is level and nothing leaks it is time to fill your tote.

Filling Your SIP And Smart Pots

You will want to add about 2-3 inches of medium. I used growstones but unfortunately they no longer make them. I recommend using chunky perlite if you can it just because smaller pieces could clog your drain screen.

Your fitting should have come with some straight extensions to adjust flood depth. You may want to use them but I did not need to. What you are after is a water level that stays about an inch or two below the surface of your fill medium.

This is important! You do not want your smart pots to sit in water! Your pots should sit on top of the perlite and the stones will allow the pots to wick water from them. The water should be below the surface.

Use Smart Pots For Your Sip

Smart parts are the natural choice for a sip grow system because they wick water. You can use plastic pots if the bottom holes are placed in the medium. But you wont have to worry about placement with a smart pot because the whole pot is a natural wick.

Smart pots filled with coco can grow really big plants. I cant see using anything bigger than a 5 gallon pot and for most grows 2 or 3 gallon pots are plenty big enough for anything short of an actual tree.

Use Coco! Avoid Peat And Potting Soil Mixes

I recommend using coco instead of peat based mixes. Peat is very acidic and they buffer it with lime which leaches out over time and it becomes way to acidic to grow healthy plants. Coco on the other hand naturally is around a  6.2 pH which is great for growing. It also doesn’t compact like peat.

My “soil” is what is called a chow mix. It is about 50% coco and 50% growstones. You can use straight coco but I prefer a bit lighter of a mix. Once you fill your pots place them on top of the medium and make sure they have good firm contact with it.

What Size Plants In Your DIY Self Watering Planter Beds?

It depends on whether you are going to be vegging in your SIP or are getting ready to flower. You can do either. If you are planning to flower you want well vegged plants, preferably they are already in your final smart pot. However you can transplant easily into coco from a smaller pot.

You can plant seedlings or rooted clones in your smart pots too. Because they have a limited root system you will need to top water them for a few weeks until their roots get to the bottom of your pot. From then on it is best not to water from above anymore.

Also, water sparingly around the stem to encourage roots to go deeper searching for water. If you over water you will have a wet pot with a  plant too small to take it all up. Not a good or healthy situation for any plant.

Timer or Not?

When I first started running my SIP I was running my pump on a timer. One hour on and 3 off but I found the system worked better running full time. Your pots should feel moist on the bottom and dry higher up.

You may notice the top of your pots starting to look dry. Stick your finger in and make sure it is moist below the top few inches. You want your soil to be at what we farmers call field capacity. This is when soil has the right air and moisture level. It will be moist enough to hold some shape when you squeeze it but there should not be any water running out when you do.

Originally I had plug flats on the tote bottoms filled with media to raise the smart pots up but I have removed them as they really were not needed. I was not sure if I would have the pots too close to the stones but it turned out they can just rest directly on the media without getting too wet.

Feeding Your Smart Pot SIP System

You can use any good nutrient mix or dry salt based nutrients depending on what you like. I use and recommend Green Planet nutrients

.

They also make an organic certified one part called Medi One people are getting great results with.

 

 

 

 

 

 

Canna would be another good choice. I like their coco specific nutes but their Aqua Vega and Flores works great in recirculating systems.

For salts Maxigro and Maxi Bloom are very popular powders a lot of people use and like.

What ever you choose please bear in mind that your nutrients will be passing through your media continually. So you dont want to use anything with heavy organics in it like bat guano, fish or blood meal or other things that will get funky in your reservoir or planting bed. You can use lighter mixes like the Medi One and you can certainly add microbes but dont use heavy organics in this system. Even if you are hand watering they will create problems in a SIP.

 Problems With Sub Irrigation Planters?

I really dont expect to have any major problems with my SIP grow system and you should not either. The only thing that comes to mind is the possibility of algae building up on the irrigation bed itself. Coco is fairly resistant to this unless it is kept over watered.

But the perlite media is in the light and has nutrients running through it so it could start to grow algae. While it is not really harmful it is unpleasant to look at. If it develops I will cut some pieces of panda film to cover it. Landscape cloth is another possibility that breathes and wont let much light through.

I will continue to update this post as my grow progresses. I usually do grow updates weekly so you might want to bookmark it and check back.

DIY SIP Grow System – Weed Wars – Revenge Of The SIPS – Day 14

Everything has been doing great and I am really starting to get excited about this SIP system. Today is day 14 and the plants have begun to flower. PPMs, pH, and temps have remained very stable and the plants are off to a great start. I have not had to water at all and that is a really nice change. Sometimes simpler is better.

Revenge Of The SIPS – Day 21 Flowering Is Full On

I have to say that my SIP planters are working even better than I expected! Everything is in full flower. The Death Bubba and Black Banana are already starting to show trichomes. The rest of the plants wont be far behind.

Day 28 Recirculating SIP Planter

Everything is working great. Plants are healthy and watering is on point. They are praying and putting on trichomes.

SIP DAY 35 GROWING CANNABIS IN SELF WATERING PLANTERS

Everything is looking great! Plants are stacked well and getting frosty. My self watering planter bed is working perfectly! Even watering and not too wet or too dry!

Revenge Of The SIPs Day 42 Plants Are Rocking!

Plants are looking fantastic on day 42. Everything looks the best I have ever seen it. Watering is on point and the Green Planet nutes are doing a great job.

SIP Update Day 42

I have been running this system for a while now and I feel it is important to update how things are going. The system works great and plants are doing very well. But I am going to make a revision.

The large growstones work great but the smaller ones are problematic. They tend to clog the drain. They dont totally block it because I have a screen over it. But they restrict flow to the point where the water level rises too high.

After several attempts to rectify the problem I decided to remove them entirely. Since large growstones are no longer available I recommend using hydroton instead. I know I recommended perlite as an alternative. I think using perlite would cause the same problems, so do not use it. Even the chunky stuff will have a lot of small particles in it and perlite breaks and can crumble easily.

I will be unveiling a system that avoids the use of any kind of stones at all. Before I do I need to test it though. Unfortunately I can not do it while this grow is going on.

If you look at the pics below you can see the small stones are gone. The plants are sitting on top of seed flats and above the water level. As a temporary wick I placed a 2 gallon smart pot under the plants and submerged the other end in the tote. This works well enough for the meantime. If you look you can see the flood and drain fittings in the tote.

Simply raising the plants up to do this was hard on the tops above the net so any other adjustments will have to wait until the crop is done in about a month.

Day 49 Flushing Begins

Day 54 Flushing Death Bubba, Black Banana, Biker Kush, Tropicanna Cookies

Flushing continues and plants are starting to fade. I turned my DIY SIP Grow System off because I decided to flush from the top manually. There is no way to get a proper flush running a bottom feed system.

I think these girls will be finished by day 63. There are still white hairs growing but also a lot going brown too. They have had 2 heavy flushes and run off was at 90 ppm. Since my tap water is 30 ppm so there is not much left in the pots.

Now it is time to get out what is in the plant itself. Usually there are a couple of weeks stored reserves. The plants should still be making some fresh white hairs when you flush. That way they can use up what the plant has stored.

DIY SIP Grow System Day 61 The End Is Near

Today is day 61 and the end is near. Not for my DIY SIP Grow System but for these plants. My system has performed above and beyond my expectations!

The only glitch was using stones that were too small in one of my totes. This is easily corrected and the next run will have larger stones in it. Other than that everything got just the right amount of water throughout the grow. There was no under or over watering and that was what I hoped to accomplish with my DIY SIP Grow System.

My plants will be taken a bit longer because I want to see more fading lower down on them. A good flush really improves quality so a few more days is not a big deal. There are still some white hairs and that means growth is still going on. Waiting a few days at the end can mean more weight at harvest so no need to hurry things up.

I am seeing some purple in the Death Bubba and also the Black Banana. The Tropicanna can go really purple and she is. But I never got much on the Black Banana and this time some buds are really purple. Not sure if better watering is responsible or some other factor.

SIP GROW DAY 66 BEFORE HARVEST FINAL

Here is a video from day 66 and plants were harvested shortly thereafter. I had planned on taking things to day 70 because I wanted a bit more fade on the lower leaves. But the plants were ready and delay can lead to a decrease in quality.

Harvest Bud Shots

Everything turned out really well as you can see from the video below. Some buds were showing more purple coloration than previously. Not sure if even watering in my DIY SIP grow bed had anything to do with it or not.

All in all I would have to say my DIY SIP grow system worked very well. So I am going to continue using it. I did replace the small stones in one tote with larger ones and made sure it was level again. I have just started a new SIP grow in the same closet and you can follow that here: https://420grower.org/animal-cookies-in-new-sip-grow/

How To Control Cannabis Stretching

Here’s how to control cannabis stretching in flower. If your plants are too tall and you dont want to top them you will need a way to stop stretch or at least manage it.

I will share a couple of more traditional techniques to manage the stretch and also some much more radical approaches that can actually stop stretching and may surprise you.

So here is my situation with plants that are too big to flower under an eight foot ceiling. Also my solution. Please dont waste your time giving me your negative comments about leaf stripping until you watch my second video. If this is too extreme for you dont do it but dont knock it unless or until you try it.

If you want to follow the full Death Bubba grow journal you can see it here: https://420grower.org/death-bubba-grow-journal/

How To Prevent Stretching

Plants can get tall for several reasons. Genetics play a huge part in how tall a cannabis plant will get. Sativa strains usually stretch the most but now many strains are hybrids so even mostly indica strains can get tall.

When you veg your plants crowding will result in taller plants. Give them room! When plants start touching each other in your veg room they will start to grow up instead of out.

Plants follow the light. When one plants branches touch another the plants sense shading and a lack of grow space so they react by growing up instead of out.

Sometimes we cant flower when we plan to because the crop in the flower room is taking longer to finish than expected. Sometimes we start our veg too early. I am definitely guilty of doing this!

The best way to prevent stretch starts out in veg. But what do you do when your plants are already too tall? That depends on timing and your comfort level.

How Much And How Long Do Plants Stretch?

Most indica varieties will double in size during the stretch. Sativa stretch can be 300%. Many strains are hybrids and some will get tall like a sativa, others will stay short and still others will be in the middle. It pays to know your strain but this is not always possible.

I would plan on a plant doubling in size. Look at the node spacing. If it is fairly long in veg you will most likely have a very tall plant but even tight node spacing does not guarantee plants will stay short.

How long a plant will stretch is also very strain dependent. Most plants will stretch for 2 weeks but some will stretch for three weeks. Some hazes can stretch even longer than that.

How To Stop Stretch In Flowering

There are 2 common ways to deal with cannabis stretching during flower. They dont stop stretch but they do help control it. The first way is to use a scrog. You spread your branches under a net or screen as they stretch. This can work really well and give excellent yields too.

The second way is similar and commonly called LST or low stress training and involves tying individual branches down. It may be used with a screen but many growers bend and tie branches down to the side of their pot.

This is really more training than stopping stretch but it can help give big lanky plants a lower profile. It really works best when plants are young. Once your plants are big and tall already you are better off using a scrog net IMO.

Now lets talk about ways to stop stretch or actually shut it down.

Leaf Stripping To Control Cannabis Stretching

What I am going to share is a more radical approach to prevent stretch and bring it under control. This is not for everybody or the faint of heart.

I understand some people are adamantly opposed to leaf stripping. That’s fine. Your plants, your choice. But I happen to believe in it. So with that said the normal time for leaf stripping is usually by day 21 which in most cases will be after stretch is done.

However I was faced with the prospect of removing a foot of growth from my plants or looking at other options. I chose leaf stripping over chopping my plants up.

Yes, many growers successfully top in early flower and it definitely will slow down and help control stretch. But I did not spend all this time growing a canopy just to whack it off just before flowering.

Stretch Stopper

Doing a heavy leaf strip on day 1 of flower will stop plants from growing taller. They will spend the first week growing back their leaves instead of stretching. Yes it will slow growth down and also add time to your grow and it should only be done to healthy vigorous plants.

After one week I am seeing significant regrowth and equally as important almost zero stretch! The plants only had 2-3 inches of stretch the first week. Regrowth has been excellent and you cant really tell the plants were leaf stripped.

This worked so well that I am considering using it as a standard practice now. Even though there are 3 different strains it has helped keep the canopy fairly even. The short video below was actually shot at lights on on day 8 but you can see this technique definitely worked to control cannabis stretching.

View this post on Instagram

Death Bubba, GG4 and SFV OG Day 7. Leaf stripped day 1. Worked great to control stretch and ladies are looking great! Grown with Green Planet nutrients under a HLG 550. • @grandmasterlevel @horticulturelightinggroup @nlggrow @greenplanetnutrients @chycannallcgp @growingexpsd @tastiterps @solfiregardens2019 • https://420grower.org/death-bubba-grow-journal/ • #gpgrown #greenplanetnutrients #deathbubba #420grower #420growers #420instagram #420everyday #420nation #mmjlife #weedlove #weedlover #weedofinstagram #mmjgrower #mmjlife #budporn #howtogrowweed #growingweed #420dotcom #closetgrow #howtogrowweedindoors #growyourownmedicine #cobled #growyourownmeds #playingwithfire #greengenesgarden #closetgrower #closetgrown #quantumboards #hlg

A post shared by 420 Grower (@howtogrowweed420) on May 12, 2019 at 6:25am PDT

I expect another week of slightly more aggressive stretching but it should slow down because I am already seeing white hairs which means flowering is close. It looks like any problems with plants getting too tall have been solved and I will continue to update their progress.

How To Get Rid Of Powdery Mildew With An…

Would you like to find out how to get rid of powdery mildew and keep it from coming back? I finally beat my PM issues by dealing with it first in veg and then with an ozone generator to kill any left over spores.

Powdery mildew can be one of the worst things a grower has to deal with, especially if it happens later in flower. If you have struggled with PM and cant seem to shake it or if you have never had it and want to avoid getting it then please watch the video below.

How To Get Rid Of Powdery Mildew Using Ozone

In the video I said the cost about $90 and that is what I paid but right now it is on sale for $70!

Why Is Powdery Mildew So Hard To Get Rid of?

Powdery mildew makes spores. They are everywhere and can easily get into your grow on your shoes, from your clothes or even your pets. They are microscopic and also very hard to kill. The white you see on your leaves is easy to kill or get off but that is not what makes it spread. Trying to kill them by spraying is a lot like throwing a hot dog down a hallway. You will never know if you got them all and even if you did they are hard to kill at this stage.

PM can be so persistent some people think it is systemic. This is absolutely untrue. In the middle ages people believed flies came from rotten meat. They could not see the eggs flies laid only the maggots so they thought flies were created from bad meat. This same faulty kind of observation leads some to believe PM is systemic. They cant see the spores so they think it comes from the plant itself.

You wont be able to get all the spores by spraying or scrubbing and I have tried disinfecting with many products only to have it return. The only thing that worked for me was ozone.

Get This Ozone Generator And Kiss Powdery Mildew Goodbye

Ozone is a gas and as such it can get into places you cant. In addition it is a powerful oxidized and can kill mold spores at high concentrations. The Enerzen Commercial Ozone Generator is light weight, very portable and very easy to use. It has a dial you can turn it on with that also acts as a timer. This unit really puts out the ozone! It can cover up to 4000 square feet and that means most grow rooms unless you are in a warehouse.

You want to avoid breathing ozone. That goes for pets too. Dont run it with plants in your grow. Keep it away from curing weed or you will lose the smell.

This is for sterilizing your grow closet or tent. I put it in my closets and run for a couple of hours. It has a built in fan to spread the ozone around but I recommend running your recirculating fans and even running your exhaust fan if you have one.

Starting Clean With Your Clones And Veg Plants

You can sterilize your grow space until the cows come home but if you keep putting infected plants in you are going nowhere fast.

Below are two products that I know work. One is organic and one has Myclobutanil which is what is in Eagle 20. I really recommend using the because it is systemic and much more effective. Use it only in veg stage, gas your room and you wont need to use anything in flower.

Adding CO2 In A Vented Grow Room

Have you ever though about adding CO2 in a vented grow room? Chances are if you did any research at all you were told co2 is only for sealed rooms. Well that’s just not true! If you are in a grow tent or closet it is absolutely possible. So read on and I will tell you how to add co2 to a vented grow.

The Truth About Adding CO2

Now I am not going to tell you the science behind how CO2 works on a biological level because there is a ton of shit about that online. But I am going to tell you how to run co2 in a vented grow room.

First you need to know co2 is not some magic elixir. You should only think about running co2 in a dialed in grow environment. It cant cure sick or crappy strains, over or under watered or fertilized plants and weak lighting. But if everything is running as it should it can bring you to the next level.

Secondly it is going to cost you some money to get started. Once you have the equipment it is pretty cheap to run co2. Don’t waste money on bags full of compost or mushrooms or whatever they fill them with. They dont work that well and cost more than refilling a CO2 tank.

What To Expect  From CO2 Enrichment

In a properly set up grow tent or closet you can expect a 25% increase in yield along with bigger, frostier and harder buds.

Say you grow 4 crops a year, which is not hard, especially with a separate veg space. Because of the increased 25% yield from growing with co2  you will actually end up with 5 crops! That’s right! ADDING CO2 IS A NO BRAINER BECAUSE YOU GET AN EXTRA GROWS WORTH OF WEED FOR ONLY THE COST OF THE CO2.

Yield increases are great but it’s even better when you can also expect better quality weed too. Buds will be harder,larger and have more trichomes.

But like I said before most people say using CO2 in a vented grow is a waste of money. Well if you run your fans constantly that might be true. But it only cost about $20 to fill a tank and a tank or 2 will probably get you through a grow and then some.

A lot depends on the size or your grow space and how tight it is. It does not need to be air tight but a tent or room wrapped withshould work fine.

My closet is 32 inches wide and 6 feet long. To make things easy I will assume it is 3′. Using 3′ x 6′ by 8′ I come up with 144 cubic feet I need to fill (L x W x H = Cu. Ft.). There are charts that you can use to estimate CO2 usage based on your footage. More on that later. My figures show at 1200 ppm a tank should last about a month but I wont know for sure for a while yet.

So who cares if some gets vented or leaks out as long as we are getting the results we want? Personally I would spend $20 a week for a 25% yield increase wouldn’t you? Think of all the shit we waste money on and get no return from.

How To Add CO2 To Your Grow Tent Or Closet

I shot a video the day after I added co2 to my grow closet and wanted to share it here. It doesn’t cover everything. But dont worry because I will go into more detail later. It does give you a good idea of how this works though.

You can also follow my grow at https://420grower.org/gelato-33-takes-over-the-grow/ That way you will be able to see my co2 grow room setup at work and decide for yourself if co2 supplementation is worth it for your grow closet or tent.

Supplemental CO2 Enrichment Day 7

I have been running CO2 for a week now. It is hard to tell a difference in the plants themselves at this point. What I can see is an increased metabolism which obviously means healthier and happier plants. They are using 5 gallons of water every 2 days and eating over 200 ppm during this time. I would say this is close to double the rate I was seeing before.

Overall adding CO2 has been successful.  So far temperatures have not really been an issue. LEDs need to be run warmer than HPS by at least 5 degrees. They do not put out any infrared so the higher temps compensate for this. Leaf surface temperature or LST is the only accurate way to measure grow room temperature so buy yourself a $20 temperature gun if you dont already have one.

Here’s What You Need To Add CO2 To Your Grow

20# CO2 Tank

At the very minimum you will need a tank and a regulator. I recommend using a 20# co2 tank for a closet or tent. They weigh about 50# full which most people can handle without much difficulty. The larger steel tanks can be over 100 pounds making them impractical for most people to tote around.

You can buy a new tank or possibly find a used one for sale but the 20 pound tanks are hard to find used. You can probably buy one at your hydro store but expect to pay more than a new tank from Amazon.

As far as refilling just about any welding supply store can refill your tank. At the hydro stores you will usually swap an empty tank for a full one. It cost me $20 to refill my tank but it may be more in other areas. You will want to buy a tank with a built on carrying handle too.

CO2 Regulator

You will also need a regulator. This will adjust the flow rate from the tank. It also has a solenoid that can open or close the flow. All regulators look about the same to me although I have a Titan Controls regulator. They range from about $50 to $80 new. You may be able to find a used one on Craigslist or somewhere like that.

You will want the micro tubing that comes with it. This tubing has laser drilled holes in it to allow the CO2 to disperse in your grow. You will hang it over your grow and because co2 is heavier than air it will fall onto your flowers. And you will also need a special fiber washer to install it to the tank. Most regulators come with these.

About Timers For CO2

Because plants only use CO2 during the day you will need a way to turn the solenoid on and off. If you have room on your light timer you can simply plug it into that. Otherwise you will need a separate timer so the solenoid closes at night and comes back on with the lights.

Some people use an interval timer set to run days only if you are going to run CO2 and fans to vent you will need this type of timer.

I will go into how to add CO2 to your grow with this method shortly.

Why You Want A CO2 Controller

Without a controller you will have no way to know exactly how much CO2 you are adding. You could be under or over dosing it. A controller will open and close the solenoid on your co2 regulator based on your settings. It cost a bit more to get started this way but you will get better results and wont be wasting CO2.

CO2 controllers vary a great deal in price depending on what you want them to do. Some act as environmental controllers that can turn on fans or heaters or air conditioners and dehumidifiers.

I am guessing most of you dont want to spend a ton of money for these so I will take a simpler approach. I am going to recommend you at least get a monitor like this:

This is the unit I am currently using. It will give you temperature, humidity and co2 levels. It works well and is nice and compact and not too expensive. But remember it is not a controller just a monitor.

I just purchased the unit below and am waiting for it to arrive. It is basically like the unit above but has a remote sensor and allows you to set a desired ppm level.

Autopilot has a pretty good reputation and I still cant believe how cheap this controller is because everything else I found was pretty much over $200. I am not sure this deal will last so if you want a controller I would jump on it.

Autopilot APC8200 CO2 Controller Review

Here is an unboxing and review for the Autopilot APC8200. You can buy this on Amazon at https://amzn.to/2OXlVXC Cheapest and best basic co2 controller and monitor I have found.

LET ME MAKE ADDING CO2 EASY FOR YOU!

In a hurry and want to add co2 to your grow fast? Dont want to search all over for all the different components? Here is a co2 enrichment kit and a great deal I found on Amazon to get you started .

How To Add CO2 In A Vented Grow Closet Or Tent

Before we start adding co2 we need to decide how we are going to do it. One way is by using intermittent flow and the other is a constant flow method.So there are 2 basic ways to go about it.

The first method involves using a timer for the solenoid and a separate timer for a fan. Generally speaking this is the most often recommended method. You use a chart like the one below to release your co2 as quickly as possible and then the solenoid shuts off. About 45 minutes later your fan, also on a timer kicks on for 15 minutes and then shuts down. Then the cycle starts all over again.

The typical level of CO2 in the air we breathe is 300 PPM. This timing chart will assist with adding an additional 1200 PPM of CO2, bringing your garden area’s CO2 level to 1500 PPM, which is considered ideal for most indoor gardens.

Along the top row of the chart represents cubic feet (CU.FT) of your garden area (length x width x height = CU.FT). The left column represents the Flowmeter setting (CU.FT/HR) which is controlled by the Flow Adjustment Knob. Simply determine your CU.FT/HR and set your Flowmeter. The chart will tell you how long to set your timer to bring your CO2 level to 1500 PPM. EXAMPLE: If you have 800 CU/FT and set your Flowmeter to read 6. It will take 10 minutes to bring the CO2 up to a level of 1500 PPM.

Ideal CO2 enrichment times range from 8-15 minutes. The quicker you can replenish the CO2 in your space the better. CAUTION: Excessive flow rates of CO2 from a tank through a regulator can cause the regulator to freeze and can permanently damage the regulator. Your garden area will determine adjustments made to this timing chart (plant maturity, drafts, leaks, etc. should be considered). Some gardens will require less time than indicated and some gardens will require more. http://sunlightsupply.s3.amazonaws.com/documents/product/702710_Instructions.pdf

This method will work but it could take some fiddling to get the timing just right. Also I think 1200 ppm is plenty and the old recommendation of 1500 may be outdated especially considering ambient co2 levels are now about 400-450 ppms and not 300. Global warming IS saving you money on co2 LOL!

I am using a constant flow. I have my flow adjustment knob set as low as it will go. So the little green ball is setting at .o5. In by closet (3 x 6 x 8) it gives me a level of 1200 ppm. Your results may vary depending on size of area and tightness of the space.

I dont like the idea of dumping it in fast and it seems you have a lot of gas leaking out before the plants can use it.  Instead I want to trickle in a steady level plants can use. I think synching fans with your regulator could drive you crazy and I dont think it is practical if you are using a controller because they are designed to maintain a constant level of co2.

Hooking Everything Up

The main thing you want to watch for is leaks. Make sure your tank is all the way off. To install the regulator you will want to screw the regulator nut onto the tank. Pulling back on the rod will make it easier to thread the fitting on. Dont forget to use the washer or it will leak no matter how much you tighten the fitting.

Once it is installed turn the tank on. Plug in the solenoid and then use the flow adjustment knob until you see the green ball start to float. Then spray the area where the rod comes out of the fitting with some soapy water. If you see any air bubbles you will need to tighten things down until there are none.

The next thing is to install the tubing that came with the regulator. Since CO2 is heavier than air you will want to get as much of it as you can above your crop so co2 rains down on it. If you dont have this tubing you can use 1/4″ airline tubing and run it to the back of an oscillating fan.

Dialing It All In – Controlling Temperature And Humidity

First things first. You want to know where your co2 levels are at. Use a monitor or controller. If you cant afford one you probably should not be running co2 until you can. In a pinch you can go by the chart I provided but you still will only be guessing at your levels. In the long run a controller will save you money on co2 usage and trips to refill your tank.

You are going to need things to run for a bit so you can see what the temperature and humidity are. In my situation my temps run in the upper 80s and humidity is 50-55% but this will vary greatly from grow to grow.

At this point I do not need a dehumidifier or air conditioner but when summer rolls around I will probably run from midnight to noon because overall temperatures will be lowest then.

I wish I could guarantee all this will work without a hitch but I cant. You may still need to run an AC. The good news is an AC will also help control humidity.

For a small space running a mini split is not really an option so what you will need is a portable AC with 2 hoses. This will pull air in and exhaust heat without sucking out your co2. The units by seem to have good reviews. I am not an ac user so I cant help you size one or chose a brand. All I can tell you is make sure it has 2 hoses.

 

Venting Your Grow

At some point you are probably going to need to vent your grow space. First lets deal with heat.

HPS Vs LED

If you are running LEDs heat probably wont be much of an issue except on the hottest days.If you are running HPS you will absolutely need an air cooled grow hood.

Not only that, but you will need to pull air from outside your grow tent. You will also need to exhaust it to the outside. So it is an air flow that is totally separated from what is going on inside your grow room. This is a good practice even if you are not running co2.

Odor Control

If you are going to grow you need to control the smell. Period. Dont think for a second that just because you dont smell anything no one else can either.

With HPS you will need to exhaust through a carbon filter placed outside your tent. If you are running LED lights you can put a fan on top of your filter and pull the air in the room through it. So you will be recirculating everything without needing an external exhaust.

Getting The Temperature Under Control

The good news is that running CO2 allows you to run your temperatures 5-10 degrees higher. Usually about 76 is considered good for HPS. We are talking about leaf surface temperature (LST) here and not room temperature.

For LED grows you want a LST of 82-86 degrees and some research says 86 is optimal for plant photosynthesis. With that in mind heat should not be much of an issue. When I was running an exhaust fan I actually had to add heat most of the year.

I dont know if this can be taken up the same 5-10 degrees like running HPS. So far I have hit 91 with no adverse affects. This usually does not happen until the last few hours of my cycle. For most of the day I am 81-86.

Passive Exhaust

When I first started this experiment I was running a passive exhaust 24/7. I disconnected my exhaust duct and left it open. My fan continued to run sucking through my carbon filter and blowing the air back into the closet. I experimented with running the passive exhaust open and closed off.

It worked fine but I did not see a need to exhaust at all because temps and humidity were pretty good so why exhaust co2 when you dont have to? I may need to go back to this when things warm up this summer and since heat rises and co2 sinks it only seemed to reduce my ppms by 2-300. So instead of being at 1200 I was at 1000 ppms.

This setup might be all you need to control temperature and humidity. Again I just want to say every grow space is different and climates are different too. Since I am in Western Washington temperature and humidity are pretty moderate most of the year. Humidity is low in the winter when the heat is on and low on sunny summer days too.

I run my exhaust fan at night to get odors , temps and humidity down on my off cycle. This works really well. I could probably set it to go on for a few minutes during lights on. I have tried this and it does not seem to remove much co2. My levels only drop about 2-300 ppm over 15 minutes. My fan is on a fan speed controller and I run it low because it is oversized for my closet.

I am just using a pin timer at this time. If you want better control you will want to use a fan speed controller like the Mercury 4 that can be set to turn your fan on and off at a set temperature and can also control fan idle speed.

One final option is to get an environmental controller. These are often run in greenhouses. They can be expensive but they allow you to synch your co2 with fans, heaters, and dehumidifiers too.

Adding CO2 To A Grow Tent Or Closet

Well that’s about it for now. You can add CO2 to a vented grow despite what all the naysayers tell you. I will continue to update this so you be able to follow my progress. If you have questions leave a comment and I will do my best to answer them.

Happy Growing. Stay Green

420 Grower