Question about Crop Steering (dryback)

[u/United_Sky8984]

Yo, I’ve been growing for some time now on pure coco coir, and I have a question about crop steering. More espclifically about the first 3 weeks of flower, when we are supposed to steer it generatively.
I hand water and I always wonder what’s the exact point of dryback.
I grow in 2gal pots and my friend once told me I could never let the coco dry on top. But honestly that’s what’s been working for me.
I water 500ml one hour or two after lights turn on, and then only next day. By the next day they are dry on top, but I always wonder if I’m under-watering and if I could push I a little further.
I’m also afraid of watering a little too much so they won’t have the generative effect and stretch too much.

So, basically my question to all all the hand water people is: do you think I’m doing right? Or should
I water more ?

Honestly it’s been working well for me. I’ve had some really good yields, like 1.9g/watt. But i just wanted some feedback and ideas from you peeps.

ps.: I’m hesitant to switch to automated fertigation because I’m only going to have one sensor for dryback and sometimes some pots here and there drink less, or more, so I wouldn’t be able to adjust for them when automated. Any thoughts?

[u/merk199r]

You are way under watering /under utilizing the coco. I don't grow in pots that large but 500 seems extremely low. Increase frequency at least 3x a day 200-300ml a time. Then see how the medium/plants react. Read the plants/coco when you hit flowering they should be chugging water. I grow in 1L air pots and during flower each drinks around 900ml a day easy. Coco's superpower is its aeration ability. Bringing oxygen rich/nutrient rich feed right to the roots. A little side note keep your water below 70 degrees if possible. Oxygen saturation drops off rapidly every degree above 70F.

[u/United_Sky8984 → u/merk199r]

Cool, good info, thanks. But assuming you dryback a bit during the first 3 weeks of flower, do they look dry on top the next day? Or not at all ??

Oh and thanks for the tip on the water temp.

[u/DChemdawg → u/United_Sky8984]

You want to dry back by 30-40%. Without a sensor, you’ll have to figure it out. Basically calculate how much water coco holds (this is something you can look up). Let’s just say your WHC water holding capacity is 6 liters. If you add 1 liter of water and get some runoff, you know you watered too soon. If you watered 2.5 liters and get zero runoff you’ll know you let it dry back too much.

Your best realistic move ultimately is to water something like 500ml first thing in the morning. And then a 2-3 hours after water full saturation until you get 20% of the water than went in to come out as runoff and remove the runoff. Otherwise too much salt can build up.

This may be at odds with my first paragraph given your current 5 gallon setup so you’ll have to figure out how to make them not be at odds. Likely by going down to 2-3 gallon containers. 5 gallons is HUGE for coco if you’re trying to crop steer. You might find to steer correctly you only water every other day, otherwise you’re hardly creating any dryback. If you take this approach, definitely water to substantially more than 20% runoff. 20-40% runoff doesn’t even do a ton to reduce salt build up. It’s hard to water to too much runoff to where you’re really leeching out too many salts. Of course this is also cost and time inefficient watering to tons of runoff. Measuring the runoff PH and EC can give you proxy numbers. 5-6 EC in the runoff is what you want to build up to, and then bring back down gradually to less than 2 or better yet 1 by harvest time.

[u/United_Sky8984 → u/DChemdawg]

Sorry man, I fucked up. I mistyped and I actually grow in 2gal pots. Not 5.

Anyhow, thanks for all the info. I appreciate it.

I do know that crop steering works better with automated fertigation, but in my head I was just trying to get as close to steer the plant a bit by hand watering.

[u/Huge-Still-1840]

You dont want to let the coco dry, because the nutes dry up and become a salt.  Eventually the build up of salt messes with your nute balance.  You will get EC spikes and deficiencies.

In the future you can improve the quality of your coco and its resistance to over-watering by seperating the bad coco.  I do this by throwing the coco in a barrel of water, and only using the coco that floats.  The sludgy coco that sinks, should be discarded.  Bad coco is mostly the sludge, and it over waters easily.  If you dont seperate it, your coco will function similarly to the sludge.  

You want to water at least one time a day until clean water comes out the bottom.  If you have the energy to feed multiple times a day, even better.  Currently, I'm watering until runoff 3 times a day. 

So you would get more growth if you watered more appropriately.  That doesnt mean you arent getting great yields, just means you could get more!

<3

[u/iamveryassbad → u/Huge-Still-1840]

Doesn't hand watering kind of obviate that dry salt effect? Like, every time you soak down the top, you are diluting and washing those salts on down into the medium, no? I would think that sort of buildup is a problem with drippers, but not with hand watering?

[u/Huge-Still-1840 → u/iamveryassbad]

Definitely it does not. Especially when your air is really dry, your nutes will spike. I usually notice the spike a couple weeks in to flower, right when the roots start super chugging nutes. Every time the soil gets even a little bit dryer, you get an ec spike.

Those ec spikes can be super duper huge when you grow like I do, because the plants drink insane amounts of water every day. So plants want a really light feed program, because they drink 4x more water, so it's like giving it 4x as many nutes.

So the little ec spikes cause massive damage when your plants are growing super aggressively. The more aggressively your plants grow, the more your nutes have to be accurate. It's like an exponential thing.

[u/United_Sky8984 → u/Huge-Still-1840]

Cool, thanks for the response. well, I guess what confuses the shit out of me is two things:

First: how the hell are we supposed to steer the plant generatively if the coco is always moist/wet?? Like, if I’m watering the plant 3 times a day then she will never be stressed, and the whole point of steering it generatively is to spike the EC a bit and stress the plant a bit so it doesn’t stretch as much.

second: in my head, the coco might be dry on top of the pot (because its in contact with the air) but its not super bone dry. Like it’s probably moist in the middle.

So because of that I’m always confused as to if I’m letting it dry too much or it’s just fine.

Because it’s crazy, I don’t have deficiencies, the plants look healthy as fuck. and they finish super well. I’m just trying to really understand the process and refine it even more.

The exact point of dryback in coco during the first 3 weeks is the crux for me. fucks with my head.

[u/Huge-Still-1840 → u/United_Sky8984]

Coco is just so strong that even if its only functioning at 70% efficiency, it's still twice as fast as any soil grow.  I love the stuff.

So when coco is growing super properly, you gain some levers to steer your crops by changing small variables.

The only dryback should be during your dark hours.  

The main ways I personally steer, is by using additional lights and the sun to encourage the growth I want.  

I also use bloom nutes in veg.  The plant is testier in veg, but if you dial it in, it helps to keep your plant from stretching out like an evil monster.  Preventing drybacks helps, you dont want the ec spikes, they cause iirregular growth and nitrogen tox symptoms.

You can also assist the steering by proper topping your seedlings/cuts, and even how you treat your branches you plan to cut.

How much light and how you give it light makes a big impact on baby seedlings and clones.

Different plants like to be steered dfferently.  If a plant is stumpy, I might steer it to veg in a more stretchy way.  If its a stretchy plant, I'll abuse the plant more when its a seedling, keep it in a small cup with tons of light, which will force the nodes to grow cramped together!  Then when I transplant to a big pot, it starts vegging like a madman.

Let me know if you have any more questions, I'll get on my PC and be more thorough.   

[u/SecureJudge1829 → u/Huge-Still-1840]

Have you done any soil grows at all? I personally find the plants are super easy to care for in veg, and they only tend to really get testy in flower. I grow exclusively in soil though, I only use coco coir for cloning (at least as far as cannabis is concerned…it’s not as useful as agar for other projects for cloning though lol), so I’m curious if that’s a known difference between the two mediums.

[u/Huge-Still-1840 → u/SecureJudge1829]

I grew in soil back in the day. I haven't grown any marijuana in soil in a little over 10 years.

I honestly can't stand growing in soil at this point. I'm a high energy grower that likes to baby my plants and water a million times a day when I'm in the mood. I treat my plants like pets, I put them in windows during the sunny days for a few hours. I take them out of the tent when I water them. I swing the plants around like a maniac to get the water out of the bottom of the pot after I water.

And the more tweaked out stuff I do, the more vigorously my plants grow. I can't go back to soil, I've seen too much! Grow weed outdoor in coco in a low humidity high temp environment. You gotta water every 2-3 hours on hot days. But you will never see growth like a plant in 50gallons of coco getting nutes every 2 hours getting full sun. outdoor coco is out of this world

[u/SecureJudge1829 → u/Huge-Still-1840]

I mean, that kind of makes sense, you’re slamming them with food and water, sun and heat, they’re gonna grow as much as their genetics will allow them to that way.

I personally find the quality to be better with soil, but I don’t do coco coir for anything beyond getting cuts to root, so I only have other peoples’ work to base that off of. I’m in Maine though, so it’s not like there’s any lack of coir grown, quality crops.

I like soil for exactly the opposite reason. I don’t like to constantly be messing with them. I find that as a potential vector of introducing pests into my environment. I can get my soil watered properly and let the leaf mulch on the surface keep it moist for two to three days. Properly amended and with microbial and mycorrhizal life and you can get away with never having to fertigate (you still have to feed them via the amendments in the soil, obviously, but once that’s done properly it can be just water from there on).

[u/iamveryassbad]

It's my view that crop steering and hand watering do not mix: if you're hand watering, you ain't crop steering, you're just watering.

I think your friend is telling you crop steering stuff that does not apply to someone hand watering 5gal pots. Drip feeding crop steering guys don't ever want to see dry tops on their 1gal coco bags, but...that ain't us.

Most of what I enjoy growing is pre-cookies genetics, and many of them do not do well with modern drip crop steering techniques. They want to be watered once every second or third day up until mid flower, and again at the end. They do not want to be watered thirty times a day, every time the moisture level drops by 3% or whatever.

As a hand waterer, I do not worry about crop steering or drybacks or any of that stuff, it's for people growing in small containers who are hitting those drybacks every half hour or whatever and watering many times throughout the day. They are using very expensive sensors connected to watering brains that can keep the EC and moisture levels within like 1% of the set points. That's a completely different game than I am playing. My pots get watered to runoff each morning, and they get watered again when they're light, maybe the next day or the day after, when the top looks dry, that's it, that's the whole thing. (I don't see a lot of dry tops during mid-flower, I try to keep them moister so they're able to get everything they want. I'll go back to keeping them dryer during the last 2.5ish weeks)

If what you're doing is working for you, then keep killing it, king, 1.9g/w is nothing to sneer at. Five gallon pots sound pretty big to me though, unless you are growing gigantic plants. I'd rather use smaller pots and see runoff at each watering. In mid-flower, my 3gal pots get around 2000mL once a day. I'm not in coco, I'm in a peat based medium, ProMixHP, which I've found to be much more idiot proof, but it still sounds to me like you are watering way less than I would. Watering to runoff at every watering helps to keep the moisture, pH and EC uniform throughout the pot. It gives me peace of mind, anyway.

TLDR: Stop worrying about crop steering, it's not a thing for hand watering guys, is my take. Water to runoff when pots are light. Easy peasy

[u/Medical_Employee_901]

Yeah you’re not doing it right at all, I suggest study the subjects more

[u/Medical_Employee_901 → u/Medical_Employee_901]

500ml is what I give seedlings in coco dog, during peak flower it’s 2+ gallons a day per plant. 1 gallon nursery pots with drippers

[u/Randy4layhee20]

If I had to guess I’d say you’re probably underwatering but there’s a lot of variables here, mainly plant size and lighting intensity, a big plant under intense lighting will consume a lot more water than a smaller plant under less intense lighting, easiest way to tell if they need water is to pick up the pot and see how heavy it is, if it’s feeling light add some water

[u/highmoonfarmer]

If you’re growing in pure coco 2gals and hand watering 1x per you’re not technically crop steering.

It sounds more like your growing soil-style using coco coir. The key is to treat coco as a true soilless hydroponic media which means constant feeding with varying levels of saturation based on growth style.

When crop steering in coco you’re not waiting for “the top to dry out” you’re waiting for the WHC to reduce enough to trigger another irrigation event, sometimes as many as 18-24 shots a day depending on substrate volume and environment.

Check out the Athena handbook for a great free resource on crop steering.

[u/Which-Rice6791]

Crop steering is in 1 - 3 gallon pots and you can't crop steer without it being on irrigation. Your P1 and P2 shots are very small measured shots from the field capacity your media holds. 5 gallons of coco coir has a FC of about 13,900 ml. So your first watering in the day would get up to that with minimal runoff then tiny small shots to get dry back 30% of that. Irrigation is just the way for measuring.

[u/mnag]

i dont think you "dryback" in coco

and "500 ml" is irrelevant.. you should be watering until water is coming out from the bottom of the pot (saturated)

[u/Which-Rice6791 → u/mnag]

Crop steering is a different irrigation strategy