Is Dry Back in coco really that damn important?

calvin.m16

calvin.m16

Well-Known Member
I notice a lot of professional and hobby growers either fail to mention or overtly mention Dry Back of the root zone.

Reading some stuff people swear Coco needs to be 100% saturated all the time and others say it needs to dry back to 50% before you water it again.

Not sure who/what to believe as I've tried both methods and honestly notice no difference.

Is this Wacky bro science or is there some valid reason to let the rootzone dry back substantially between waterings particularly in coco?
 
Hook Daddy

Hook Daddy

Well-Known Member
The roots also need oxygen. I believe the more perlite you add with the coco, the more you can water, and at 50/50 you can just about water continuously without drowning the roots. Coco holds water well, so with no perlite you water to waste, then wait to dry some, but never actually dry.
 
Hollatchaboy

Hollatchaboy

Well-Known Member
Wizzlebiz said:
People say don't let it dry out.

I dont think I ever saw anyone say keep it saturated at all times.
Click to expand...
I've heard it before too......

"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."

That was from a Google search.
 
calvin.m16

calvin.m16

Well-Known Member
Hollatchaboy said:
I've heard it before too......

"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."

That was from a Google search.
Click to expand...
This is what I have noticed. Athena for example says in coco on their feed chart allow 50% dryback but when letting plants do that they seem stunted. If I fully saturate they seem to be blowing up.

I'm running 70% Coco 30% Perlite blend with Jacks 12-4-16 RO but plan to switch nutrients soon cause it goes way faster than they advertise.
 
coreywebster

coreywebster

Well-Known Member
It's a thing from some other real gardening method isn't it?

I'd not heard of it until the last few years.
Not sure where it spung up from.

I water several times a day in flower .

But for a lot of years I treated it like soil and watered every 2 or 3 days.

I don't think my weed now Is better or worse than back then but I don't have the local ability to test it outside of customer feedback.

One thing I know is I am less likely to run into problems, lockouts ect now I don't allow it to dry out.

Anybody want to explain the importance of the concept?
 
calvin.m16

calvin.m16

Well-Known Member
coreywebster said:
It's a thing from some other real gardening method isn't it?

I'd not heard of it until the last few years.
Not sure where it spung up from.

I water several times a day in flower .

But for a lot of years I treated it like soil and watered every 2 or 3 days.

I don't think my weed now Is better or worse than back then but I don't have the local ability to test it outside of customer feedback.

One thing I know is I am less likely to run into problems, lockouts ect now I don't allow it to dry out.

Anybody want to explain the importance of the concept?
Click to expand...

blog.growlink.com

Dry Back Percentages Explained | Irrigation Tips | Growlink

Learn about the growth strategy that uses dry backs as a way to stress plants into a generative or vegetative growth stage to increase harvests.
blog.growlink.com blog.growlink.com
.

Seems like Growlink explains it but of course they sell products so I kinda take their information like nutrient companies. Hard to believe stuff when there's sales involved. Not gunna lie though their system seems pretty nifty, you can monitor EC, temp, moisture of multiple plants and have their computer automatically apply the crop steering and dry backs. Looks like it costs a pretty $1,000+ for their full system though. :shock:

I think I'll save $1,980 and use my cycle timer and tinker with that to get the right moisture content I'm looking for.

IDK I've tried both watering daily, every other day and just watering every day keeping them pretty much fully saturated other than at nighttime works best.. As you said letting it "dry" at all while running coco and salt based fertilizer just seems like a nono.
 
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Rurumo

Rurumo

Well-Known Member
When coco dries the EC skyrockets. If it dries a little, the EC goes up a little (and vice versa)...So some dryback won't be that noticeable. I've been experimenting with this by using 1.5 g, 2 g, and 3 g pots all fed twice per day. The smaller pots get substantially more "dryback" but it's still not enough to derail them...however, they yield less than the bigger pots, simply because the larger root balls are exposed to a more idea concentration of nutrients at the root zone for longer AND also a bigger root ball means more surface area exposed to and collecting nutrients. The whole point of multifeeding in coco is to constantly refresh the nutrient levels at the root/soil interface.

Another factor is the EC you start with. If you run "low ec" (around 1) then you might not notice much tip burn or other leaf issues as you would if you run a "high EC" because the peak EC will be lower if it starts lower to begin with. This is why you can get away with pretty much as much dryback as you want with seedlings being fed very low ECs-letting the pots get light and even visibly dry, doesn't really hurt them because the peak ec at dryback never gets too high, and a wet/dry cycle helps fill the roots out.

As for what is ideal, studies have shown about a 20% increase in yield when going from 2 fertigations per day to 5 fertigations per day. So setting up an automated system and keeping that fully rooted media fertigated 5 times per day does increase yield by keeping an optimum concentration of nutrients in the root zone at all times, BUT...it's 20%. For a commercial grower, it's a nonstarter, I would absolutely keep the media more moist with multifeeds 20% is huge commercially...but at home, I'm happy with 2 feeds per day for plants that have filled out their containers with roots. I never multifeed until a transplant has a full root ball.

Keep in mind fiber length of the coco you use too. Fine fiber coco holds much more water (and much less air) than longer fiber lengths. Fine fiber coco is manufactured to mimic peat much more closely. I see new growers have trouble with seedlings all the time in coco, and it's usually down to overwatering in fine fibered coco. Of course, any difference in how you treat a plant based on the fiber length of your coco disappears once the roots fill out. Perlite makes zero difference if your coco is medium to long fiber already, and with short fiber you could add some perlite and lower it's ability to retain water....but why not just buy different coco in that case or simply make watering adjustments until the root ball forms? Any coco is easy to adjust to once you know it's characteristics.
 
calvin.m16

calvin.m16

Well-Known Member
Rurumo said:
When coco dries the EC skyrockets. If it dries a little, the EC goes up a little (and vice versa)...So some dryback won't be that noticeable. I've been experimenting with this by using 1.5 g, 2 g, and 3 g pots all fed twice per day. The smaller pots get substantially more "dryback" but it's still not enough to derail them...however, they yield less than the bigger pots, simply because the larger root balls are exposed to a more idea concentration of nutrients at the root zone for longer AND also a bigger root ball means more surface area exposed to and collecting nutrients. The whole point of multifeeding in coco is to constantly refresh the nutrient levels at the root/soil interface.

Another factor is the EC you start with. If you run "low ec" (around 1) then you might not notice much tip burn or other leaf issues as you would if you run a "high EC" because the peak EC will be lower if it starts lower to begin with. This is why you can get away with pretty much as much dryback as you want with seedlings being fed very low ECs-letting the pots get light and even visibly dry, doesn't really hurt them because the peak ec at dryback never gets too high, and a wet/dry cycle helps fill the roots out.

As for what is ideal, studies have shown about a 20% increase in yield when going from 2 fertigations per day to 5 fertigations per day. So setting up an automated system and keeping that fully rooted media fertigated 5 times per day does increase yield by keeping an optimum concentration of nutrients in the root zone at all times, BUT...it's 20%. For a commercial grower, it's a nonstarter, I would absolutely keep the media more moist with multifeeds 20% is huge commercially...but at home, I'm happy with 2 feeds per day for plants that have filled out their containers with roots. I never multifeed until a transplant has a full root ball.

Keep in mind fiber length of the coco you use too. Fine fiber coco holds much more water (and much less air) than longer fiber lengths. Fine fiber coco is manufactured to mimic peat much more closely. I see new growers have trouble with seedlings all the time in coco, and it's usually down to overwatering in fine fibered coco. Of course, any difference in how you treat a plant based on the fiber length of your coco disappears once the roots fill out. Perlite makes zero difference if your coco is medium to long fiber already, and with short fiber you could add some perlite and lower it's ability to retain water....but why not just buy different coco in that case or simply make watering adjustments until the root ball forms? Any coco is easy to adjust to once you know it's characteristics.
Click to expand...
Now this makes sense and using my BlueLab Pulse meter I've noticed the lower the moisture content the higher the EC reading. I too have noticed bigger pots simply produce bigger buds & yields. I run 10 gal pots of coco and have found with the pump & water halos I have fertigating with a cycle timer every hour for 10 seconds seems to be the sweet spot. Pots don't get too heavy or over saturated. I have DEFINITELY noticed an increase in yield & growth feeding a steady solution throughout the whole lights on period vs sploshing water on them once or twice a day.

p.s I use Mother Earth 70/30 Coco/Perlite, its definitely more of a coco pith than coco fiber.

Hat off to ya.
1669543334958.png
 
coreywebster

coreywebster

Well-Known Member
. THE IMPORTANCE OF CROP STEERING
When talking about feeding, every strain has its own needs so crop steering is highly important, especially for big commercial growers. Using crop steering allows growers to allow the plants to grow to their full potential and bring out the most of each plant. Independent research conducted in commercial facilities has found that crop steering can increase total terpene, THC, and overall cannabinoid content when achieving specific water content levels and dry back amounts, despite being hard, automating this process can help you bring out the full potential of the strains you’re working with. So by going back and forth between generative and vegetative growth you can ultimately grow plants that aren’t too leafy while producing excellent quality flower and maximizing quantity.

Now, all strains have an optimal balance between leaf and bud growth so for a 12-week grow cycle, it’s vital to be able to regulate the first 3 weeks of plant growth in order to set the plant for the remaining 9 weeks. This happens because the first three weeks of plant growth are essential, if you fail to steer your crop during the initial weeks of plant growth, it might be too late. Remember there’s definitely a limit and you should not push your plants too hard, in case you feel like you’re pushing them too much, you can avoid stress by decreasing the EC or watering with less frequency until you find the sweet spot.



How Often Should I Water My Cannabis Plants
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How Often Should I Water My Cannabis Plants?


There’s the need to experiment in order to find the right balance for each specific cannabis plant genetics, this means that in order to find the right balance you will have to experiment for a couple of grow cycles until you can provide your plant with what it needs to produce the best quality and yields that it can possibly produce. Just keep in mind that you’ll always be limited to the plant's genetic potential, sometimes you will be able to get better yields and sometimes better quality, but at the end of the day, you need to start with good genetics in order for this to work as some strains may produce excellent flower but not the yield you want or produce high yields but not very good in terms of cannabinoid and terpene content
 
klx

klx

Well-Known Member
calvin.m16 said:
I notice a lot of professional and hobby growers either fail to mention or overtly mention Dry Back of the root zone.

Reading some stuff people swear Coco needs to be 100% saturated all the time and others say it needs to dry back to 50% before you water it again.

Not sure who/what to believe as I've tried both methods and honestly notice no difference.

Is this Wacky bro science or is there some valid reason to let the rootzone dry back substantially between waterings particularly in coco?
Click to expand...
If you let it get too dry then the EC will get too high, if you keep it too wet then you will be invaded by an army of gnats. The key is keeping it hydrated just right that you have neither gnats or burnt plants. In my opinion the first feeding of the day should be just before the plants are thirsty. Crop steering is just the latest marketing bullshit to get you to buy a bunch of shit you dont need.
 
Snowback

Snowback

Well-Known Member
calvin.m16 said:
I notice a lot of professional and hobby growers either fail to mention or overtly mention Dry Back of the root zone.

Reading some stuff people swear Coco needs to be 100% saturated all the time and others say it needs to dry back to 50% before you water it again.

Not sure who/what to believe as I've tried both methods and honestly notice no difference.

Is this Wacky bro science or is there some valid reason to let the rootzone dry back substantially between waterings particularly in coco?
Click to expand...
Reading through the articles on the CANNA site, they claim that it should dry out 50%.
 
B

Bud man 43

Well-Known Member
Totally saturated coco/perlite mix with proper drainage is around 20% oxygen- I have had better results keeping it wet.
I feed at least 1 time per day early in veg- move on to twice a day starting 3-4 weeks before going to flower- then giving as much as they will take the first 4 weeks of flower until they stop drinking.
When I started I was letting it dry out 1-2 days in between watering and I experienced herms and lower yields.
Coco is better- wetter, unlike soil you really can’t overwater- overfeed yes- buy it is hard to overwater unless it is not draining properly.
 
I

inth3shadowz

Well-Known Member
All depends on container size for Coco...Im doing 5 gallon 70/30 this round DTW and do every 3 day to runoff in veg and every other in flower. For a smaller pot, you'd obviously need to water daily, but I see absolutely no difference. I'm currently testing a plant with a SIP Grobucket attachment with coco and it seems to really enjoy the bottom feeding with foliage pro. Pour feed water down the hole and keep your coco perfectly watered.
 
VincenzioVonHook

VincenzioVonHook

Well-Known Member
Rurumo said:
When coco dries the EC skyrockets. If it dries a little, the EC goes up a little (and vice versa)...So some dryback won't be that noticeable. I've been experimenting with this by using 1.5 g, 2 g, and 3 g pots all fed twice per day. The smaller pots get substantially more "dryback" but it's still not enough to derail them...however, they yield less than the bigger pots, simply because the larger root balls are exposed to a more idea concentration of nutrients at the root zone for longer AND also a bigger root ball means more surface area exposed to and collecting nutrients. The whole point of multifeeding in coco is to constantly refresh the nutrient levels at the root/soil interface.

Another factor is the EC you start with. If you run "low ec" (around 1) then you might not notice much tip burn or other leaf issues as you would if you run a "high EC" because the peak EC will be lower if it starts lower to begin with. This is why you can get away with pretty much as much dryback as you want with seedlings being fed very low ECs-letting the pots get light and even visibly dry, doesn't really hurt them because the peak ec at dryback never gets too high, and a wet/dry cycle helps fill the roots out.

As for what is ideal, studies have shown about a 20% increase in yield when going from 2 fertigations per day to 5 fertigations per day. So setting up an automated system and keeping that fully rooted media fertigated 5 times per day does increase yield by keeping an optimum concentration of nutrients in the root zone at all times, BUT...it's 20%. For a commercial grower, it's a nonstarter, I would absolutely keep the media more moist with multifeeds 20% is huge commercially...but at home, I'm happy with 2 feeds per day for plants that have filled out their containers with roots. I never multifeed until a transplant has a full root ball.

Keep in mind fiber length of the coco you use too. Fine fiber coco holds much more water (and much less air) than longer fiber lengths. Fine fiber coco is manufactured to mimic peat much more closely. I see new growers have trouble with seedlings all the time in coco, and it's usually down to overwatering in fine fibered coco. Of course, any difference in how you treat a plant based on the fiber length of your coco disappears once the roots fill out. Perlite makes zero difference if your coco is medium to long fiber already, and with short fiber you could add some perlite and lower it's ability to retain water....but why not just buy different coco in that case or simply make watering adjustments until the root ball forms? Any coco is easy to adjust to once you know it's characteristics.
Click to expand...
Exact reason I cut my yard soil (fine sandy loam) with long fibred Coco and pumice. Helps drastically with drainage and oxygenation. I'm in a potting mix (40:40:20 yard soil/Coco/pumice) and manage to feed daily with constant praying to the artificial sun gods. Been watering daily since birth in this mix. At the moment I put through a gallon on Monday to runoff, then Tue/wed gets about a litre with no runoff and then back to a gallon. I never really see the top dry out at all..
IMG_20221126_124435.jpg
I have noticed all the seeding mixes here are overly fine, especially the Coco mixes. They always seems to compact and I have to dig the seedlings out to get them to emerge .
 
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Scuzzman

Scuzzman

Well-Known Member
I grow autos in 3 gallon fabric with 100% med /fine coco coir, I find the issues start with dry back , I feed (hand water)every 10-12 hours each plant will take 3.2 ltrs of water/feed with 5-8% run off- EC spikes really bad mid/late in flower , found when using coco coir 100% pots need to be off the ground with at least a 2 inch air gap for air circulation to help dry out the bottom coco coir in the fab pots or it will stay wet/stodge and the EC really spike creating all sorts of issues ... ( setting up new auto watering system for 4 water/feeds per day)
 
N

nxsov180db

Well-Known Member
Dry backs push the plant into generative growth (flowering) on a small scale. If you don’t have automated irrigation then don’t bother with it. It increases yields (also on a small scale). In a commercial setting it matters, in a tent it doesn’t.
 
Hollatchaboy

Hollatchaboy

Well-Known Member
inth3shadowz said:
All depends on container size for Coco...Im doing 5 gallon 70/30 this round DTW and do every 3 day to runoff in veg and every other in flower. For a smaller pot, you'd obviously need to water daily, but I see absolutely no difference. I'm currently testing a plant with a SIP Grobucket attachment with coco and it seems to really enjoy the bottom feeding with foliage pro. Pour feed water down the hole and keep your coco perfectly watered.
Click to expand...
How do you runoff the waste?
 
I

inth3shadowz

Well-Known Member
Hollatchaboy said:
How do you runoff the waste?
Click to expand...
I bought these plant caddys off Amazon that have water catcher trays at the bottom. I water, smoke a Doobie for 30 min, come back and just empty the trays. Its very simple and very effective lol only downside is you can't use them if you have a low ceiling as they add a few inches to height.
 
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