HOW TO WATER COCO FOR BEST RESULTS.

[Madmax]

Yeah i cant feed over that.day 26 in flower im feeding between 550-600ppm at 500 scale.

 

[Kgunge]

I feel like it should be said that if you have big pots of coco and no perlite watering is going to work out differently.

Hey Aqua , what do you mean by this. How would watering be different ? I’m assuming less frequency since bigger container.
We’re in 20gal pots and feeding once a day 3gal at a time until a bit of runoff.
70/30 coco perlite with a bit of worm castings, will be trying out a few plants with vermiculite next run as it seems my plant is getting to dry according to this threads standards.
this goes against everything man but Damn if you guys really vouch for feeding and keeping saturation points at 70-90% even in early veg.... I’ll trust in the threads experience

 

[Aqua Man]

Hey Aqua , what do you mean by this. How would watering be different ? I’m assuming less frequency since bigger container.
We’re in 20gal pots and feeding once a day 3gal at a time until a bit of runoff.
70/30 coco perlite with a bit of worm castings, will be trying out a few plants with vermiculite next run as it seems my plant is getting to dry according to this threads standards.
this goes against everything man but Damn if you guys really vouch for feeding and keeping saturation points at 70-90% even in early veg.... I’ll trust in the threads experience

The air exchange becomes less as you go deeper into the media (further from exposure to air) so a large pot benefits for perlite of 50% to ensure this. But that also means more watering. The more compact the media the lower the air holding capacity and gas exchange. Not usually an issue until we get into really fast growing plants or plants driven hard.

In your case 70/30 in large pots you may want to keep closer to 70-80% saturation since you have less than 50% perlite and added worm castings both will increase the eater table and water to air ratio. More perlite will lower the water table and increase air to water ratio.

But if you say add 20% vermiculite to the mix and drop the worm castings you can likely run high fertigation without issue.

There are stages of growth where you may want to reduce watering a bit if starting small plants in big pots. Like once the tap root hits the bottom until the roots are growing above the water table.

What I would do is get some clear containers with drainage and take your current mix, a mix with 50% vermiculite, a mix with 30% perlite/ 20% verm and saturate them all then give a few hrs to drain and see where the water table is for each. This will give you a good idea of how to adjust your watering at what stages. If your using amended coco.

Also slow pour and measure how much water it takes to saturate before getting runoff.. do the slowly. You will be able to see which media is holding the most water and where the water table sits

It is possible to create a media that holds more water with an equal water table height. This would benefit you by watering less often and still having a high air holding capacity and good gas exchange.

Eg... vermiculite provides good drainage but also holds a good amount of water. Imo you always want to use course verm and perlite.

So you can make a bunch of test mixes to see what gives you a nice low water table and holds a good amount of water.

 

[Aqua Man]

I'm also thinking but have not tried that addition of a surfactants or wetting agents (some of our premixed soils contain) will reduce the water table height by lowering the cohesion effect. Adding this to the other thread.

 

[Kgunge]

Was going to start a new thread on this but thought I'd put this is here seen as this thread is already about watering coco...

Was watching a video on jungle boys talking about very high ec levels. Two days ago I noticed a few of my plants out of my 19 DTW had a run off ec of 3.0 (these plants have been getting a little less run off to the rest because they are a week or two in front of the others so roots system probably bigger) of cause I panicked straight away and started putting a few liters of res nutes through them to bring the ec down to around feed level which was 1.7

After I'd done that I looked at the plants and thought why have the plants not 'told me' the ec was high in the coco from nute burn or whatever reason... In fact they look amazing, after watching them videos jungle boys build the ec up fairly slowly and don't let the the media go dry, they say this is what causes burns when they go dry? Also they say a ec of 3.0 is not a problem in coco?

It seems like the standard go to ec is about 1.4-1.8 this is what I stick to. they do say some strains will do best at 1.6 but some strains won't show full potential until a ec of 3.0+ is reached. So if I was seeing no sign of stress at these high ec run offs is that my plants saying they can handle more?

But then it got me thinking more, if my plants can handle more why is the ec building in the first place? My coco is always wet with little run off every water so salts can't build up from drying out so surely this is the plants saying we don't need all that so we're leaving it behind, but this must also be the same with this guys in their big commercial places, I follow a few guys on IG and nearly all are running ec way over 2.0 with no problems... Also if you look at Athens which a lot of these big guys use, Athens says never let you ec go more than 1 over base, so if you have a base ec of 3.0 and the run of is 3.8 this is fine, and this also seems to correspond with what the guys using it do.

Now obviously I understand these are in purposes built commercial grow rooms sticking to vpd and using co2, but why does that stop us from pushing our plants a little if they can handle it and we have a dialed in room?

What do you guys think?

It also depends if you’re running C02. If you aren’t , you’re maxed out at a certain EC, room temp, and light intensity.
studies have shown with 1500PPM of C02 the most growth / photosynthesis happens at 1100 PAR , 86F , and higher EC.

 

[Kgunge]

Best £180 I've spent in a while! No more chasing runoff numbers it's great

I did a test the other day and this shows how important it is to keep coco around 90%+ saturated (some of mine do drop into the 80's not all plants dry at the same pace) I took a few feeds out from the schedule and let coco dry to around 60% and within 24 hours the ec had jumped from around 2.0 to over 3.0. I didn't flush just added the feeds back in and within 24 hours they was back to my input ec levels.

What I also found is feeding at 1.4-1.7 with little to no runoff I could let the coco dry to around 60% and the ec would drop in the pots, when increased to 2.0 if the coco dropped to 60% buildup would happen. Some might say 1.4-1.7 is a good level to feed at because ec is dropping so they're eating all that's being given, but I'd rather push my plants just that little bit and from what I'm seeing it's working.

It's a brilliant tool I know exactly what's going on in the root zone, I have 3 plants that I'd grown from seed the ec drops so fast in the pots after a feed that Im now having to feed them at 2.8ec and the ec is still dropping slightly, before I had the pulse I thought I was over feeding them because the buds just wasn't really growing, since I've upped the ec for them I've seen a increase in growth

What device / app is this from these screenshots ? What does it do?

 

[Kgunge]

They do because when you suppliment co2 the plant is photosynthesizing more efficiently which lowers transpiration rates. That's part of the reason we run higher temls and a lower humidity to help offset this and make the co2 more effective. Also feed a higher ppm.

Because it slows transpiratiin rates... VPD is designed to regulate transpiration for optimal growth and co2 uptake but an increase in co2 will result in reduced transpiration so we need to run a lower humidity to make up for this.

Another totally new concept that you don’t hear much often... how c02 effects VPD accuracy. Just when you think you heard it all now I have to figure out how this plays LOL all I know is we max out at 1200PPFD in our 80 light room with max C02 @1500ppm. Always wondered why humidity was getting higher as C02 went up

 

[Aqua Man]

Another totally new concept that you don’t hear much often... how c02 effects VPD accuracy. Just when you think you heard it all now I have to figure out how this plays LOL all I know is we max out at 1200PPFD in our 80 light room with max C02 @1500ppm. Always wondered why humidity was getting higher as C02 went up

Your burner also puts off water vapor too.

 

[Kgunge]

I'll have to dig up more articles if you like but just plucked this in 2 sec.

Can CO2 influence plant transpiration and biodiversity?

Guest post by Michael Forster, Edaphic Scientific Pty Ltd Everyone knows that plants need carbon dioxide to grow. But fewer people know that carbon dioxide can also effect plant transpiration and even the water balance of entire ecosystems and catchments. Even fewer people know that carbon...

www.co2meter.com

Fkn wow as I continue to read this whole thread & comments you continue to give us a million dollars worth of game for $9.99

 

[Aqua Man]

Another totally new concept that you don’t hear much often... how c02 effects VPD accuracy. Just when you think you heard it all now I have to figure out how this plays LOL all I know is we max out at 1200PPFD in our 80 light room with max C02 @1500ppm. Always wondered why humidity was getting higher as C02 went up

If going by VPD using true leaf temps (for those not understanding see link at bottom) WITH co2 I find lowering by 5-10%Rh of those values works for me.

VPD (vapor pressure deficit)

Ok i was gonna sit down and write out a whole article but i have been lazy so instead instead I'm going to copy paste because im lazy. This is not my work so let start. You may find this very long but its worth the read. Some may want to skip ahead. I have added here and there to what i feel is...

www.thcfarmer.com

 

[Aqua Man]

Also to be clear like most things there is not one right way... but you can up feed ppm with co2 or increase transpiration.

It's a balancing act. As transpiration also cools the leaves and transports nutrients so while co2 actually improves water efficiency we still need to make sure we are getting a decent transpiration rate for other reasons.

For this reason I run co2 at 1200ppm as I have not seen any benefit to higher yet.

 

[Kgunge]

Also to be clear like most things there is not one right way... but you can up feed ppm with co2 or increase transpiration.

It's a balancing act. As transpiration also cools the leaves and transports nutrients so while co2 actually improves water efficiency we still need to make sure we are getting a decent transpiration rate for other reasons.

For this reason I run co2 at 1200ppm as I have not seen any benefit to higher yet.

I hear you , that’s why I’m trying to wrap my head around transpiration rates and how those rates are affected by other environmental factors.

 

[Frankster]

Ok writing this cause i see this issue often and rather have a thread to link than explain this each time. This is not my work but a collection of info from many members here and I have put into practice myself.

So first off COCO is NOT soil. For best results we want to keep it saturated between 90-100% that does not mean you can't go below this but you may see slower growth or nutrient issues over time if your consistently letting COCO get to dry.

Coco has an amazing gas exchange and air holding capacity when compared to soil. For this reason it is next to impossible to over water. Over watering is NOT to much water... its lack of o2. You will see this in soil with less drainage but because of coco's high drainage, air holding capacity and gas exchange its highly unlikely to see this in coco.

I do suggest if growing in more than 1 gal pots to add perlite if you are seeking faster grow rates. However if you want to water less often then you can eliminate the perlite as this will lower the drainage. As a rule of thumb:

1gal no perlite
2gal 20% perlite
3gal 30% perlite
4gal 40% perlite
5+gal 50% perlite

You can do more or less but it will affect the frequency of watering required. More perlite the more frequent you will have to feed. Personally I feel the better the drainage the faster the growth but its a balancing act and the above ratios i would say are a great place to start.

Coco has a low CEC (cation exchange capacity) so it does not hold onto nutrients as well as something like soil so we feed with every watering to keep a balanced nutrient ratio, ph and ppm in the coco. To do so we also need to flush out some of the last feed with each feeding to prevent a nutrient buildup which can affect all of these. THINK OF COCO AS SOILESS... much closer to hydro and very similar to rockwool.

I won't get into ppm in detail as thing will change quite a bit from grow to grow depending on many factors. But generally speaking start at around 300-400ppm and work up to around 800ppm. Now some may need to alter that as it will depend on your specific grow conditions.

HOW OFTEN DO WE FEED!!!

Ah the always debated subject.. 2 times a day, 1 time every 2 days, 10 times a day????

Forget that nonsense... like I say each grow is different so we need to use a better method. Let the plants tell you!!!!

Ok here is how we calculate it simply to your specific grow conditions, stage of growth, pot size and every other variable. You will never need to wonder am I feeding to much or to little again.

The formula:

1.Feed 5% of the pot size as your nutrient solution.
2. Of that we want 10-20% to come out as run off.
3. If you get more you can lower the frequency.
4. If we get less we need to increase the frequency and for that feed we need to add more to get our run off.

So I will do the calculations up to 5gal below to save you all some time. Feed the amount listed and check to make sure you get runoff of the amount listed from there adjust to dial in the feedings as they will change as the plants grow.

REMEMBER THIS IS A GUIDLINE AND NOT A HARD RULE. Our goal is to get as close as reasonably possible. It's not gonna kill your plants if its not exact.


I'm gonna round up.

1gal. Feed 250ml get 25-50ml of runoff

2gal. Feed 500ml get 50-100ml of runoff.

3gal. Feed 750ml get 75-150ml of runoff.

5 gal Feed 1litre get 100-200ml of runoff.

By doing this your plant will tell you how often you should be watering for best results.

Plant transpiration happens during photosynthesis so we only need to water during the lights on period. But in smaller containers you may find that you need to fertigate once in the middle of lights out if fertigation events are higher. Its unlikely but if your coco is dry before the first feed its not a bad idea to toss one in. Generally feed a couple hrs before lights out for the last time but you want to split the events evenly throughout lights on.

It may sound like you will be watering way to much but when you calculate how much you are feeding and then the frequency its not much more than most already do, just supplied in a manner that provides much greater stability. You will be using much smaller amounts of nutrient solution and by feeding much more frequently it doesn't take much to get your runoff while keeping the rootzone ph, ppm and moisture content ideal.

Yea, I"m noticing about 250ml starting out with my 1 gallons per day, and once the roots seem to fill out, I'm probably going to be around 500 ml. This is all great stuff your putting out with these post, very useful information indeed. Growth is simply exploding right now, I probably need to back of the EC right now, because it's testing in at just under 1200, which is probably too much at this point. I just wanted to see how much it would actually take, without going over. So I think I found the sweet spot.

When I clean them out occasionally with yukka gold surfactant and add in a little more microbes/fungi all over to make sure it's hitting on all cylinders, I give her a bit of that concentrated humic acid, it doesn't take much, but I think that helps burn up/recharge the nutes that accumulate over time.

 

[Aqua Man]

Yea, I"m noticing about 250ml starting out with my 1 gallons per day, and once the roots seem to fill out, I'm probably going to be around 500 ml. This is all great stuff your putting out with these post, very useful information indeed.

I hit 14x a day last grow start to finish in 1 gal pots... Doesn’t seem to matter the pot size as long as the roots have access to a stable PH,nutrients and ample water and o2 for thier size.

Imo more root is not more fruits but there is some truthfulness to that. As it came from a time when most grew in soil. The bigger the roots system the more access it has to those. But being able to do the same thing in smaller pots has kinda changed that in my view.

Now with the exception of organic nutrients that only become available at a certain rate that more roots more fruits would definitely apply as in a small container the would not be enough organics converted into available nutrients to sustain the plants even if fertigation was as described.

That why when I do it I will use a mix of organically derived nutrients (for availability) and slightly larger pots.

 

[Frankster]

Temps, and humidity are going to factor in here somewhere also, accelerating or retarding water evaporation rates. Once I get close to the flowering stages, I really start to dial the humidity levels downward, and I notice a big increase in the amount of water loss by emptying a few gallons from the dehumid unit, everyday. X so many plants, that's got to be a pretty considerable amount of water per/plant.

 

[Sparky1980]

Apologies if this was asked before @Aqua Man, but what is your opinion on adding dry organic nutes to coco + perlite mix and then simply watering with RO water? Some dude on the tube does it with good results. I was thinking of trying.

 

[Aqua Man]

Temps, and humidity are going to factor in here somewhere also, accelerating or retarding water evaporation rates. Once I get close to the flowering stages, I really start to dial the humidity levels downward, and I notice a big increase in the amount of water loss by emptying a few gallons from the dehumid unit, everyday. X so many plants, that's got to be a pretty considerable amount of water per/plant.

The biggest contribution will be the overall leaf surface area. Also the lower your humidity setpoint the more water the plants will expel.

 

[Aqua Man]

Apologies if this was asked before @Aqua Man, but what is your opinion on adding dry organic nutes to coco + perlite mix and then simply watering with RO water? Some dude on the tube does it with good results. I was thinking of trying.

Absolutely doable... I believe you are referring to Mr Canuck?

You will want a slightly larger pot size than say like I used 1 gal and synthetic nutrients.

understanding that organic nutrients are not available to the plants until they are broken down in ionic form (salt form).

If you think of it this way each sq inch of media with organics will have X amount of nutrients that break down into available form slowly over time. So unlike synthetic you need to ensure the media as a whole will provide enough nutrients (with synthetic we just feed more nutrient solution as these are already in ionic salt form) so depending on the size of the plants you intend to grow this needs to be considered.

Also when using organics you do not want to water to runoff as runoff will take some of the available nutrients out of the media... unless you added to much in which case it would help. But ideally we don't want runoff in any media when using organic amendments.

 

[Sparky1980]

Absolutely doable... I believe you are referring to Mr Canuck?

You will want a slightly larger pot size than say like I used 1 gal and synthetic nutrients.

understanding that organic nutrients are not available to the plants until they are broken down in ionic form (salt form).

If you think of it this way each sq inch of media with organics will have X amount of nutrients that break down into available form slowly over time. So unlike synthetic you need to ensure the media as a whole will provide enough nutrients (with synthetic we just feed more nutrient solution as these are already in ionic salt form) so depending on the size of the plants you intend to grow this needs to be considered.

Also when using organics you do not want to water to runoff as runoff will take some of the available nutrients out of the media... unless you added to much in which case it would help. But ideally we don't want runoff in any media when using organic amendments.

Word. That's the detail I needed. Thank you, sir!

 

[Bbonez]

I'm trying this type of grow this run and am happy with the results. I was growing under 2 SE 1000w HPS and 1 Diablo but my 420 sale Diablo came in yesterday so I switched one of the HPS lights out. Everything is looking good but I can't get the runoff under control. I feed @3.0 or 1500PPM & 5.5 PH. I was watering 7 x a day and the runoff kept creeping up. Finally hit 2700 two weeks ago so I started a flush, 1st cut the feed in half, then increased amount of water per feed. Took about a week and I got the runoff down to 1600. I'm only feeding 3x a day now but more per cycle. Anyway as soon as I went to a normal 20% runoff schedule the runoff shot up quick. Plants don't look to have an issue but I want to be proactive if this could lead to a problem, any suggestions?