as far as adding epsom salt how much is the recomended dose and does it mess the the chemical compounds of different nutrients thus causing another lockout or is it safe to use with any base nutrient
first coco grow having major problems!!!! help please
- Thread starter aktattoo
- Start date
G
guest1ab
You got to water everyday, too. You know that right?
knna
Member
There is two basic schools of growing in coco coir.
One just translates the parameters of general hydro growing and modify it a little to work fine in coco. It consist on using a ph range 5.8-6.2 and add Epsom Salts (mainly Magnesium Sulphate, MgSO4) to compensate for the higher percentage of Mg vs Ca uptaked on this regime.
The other uses a lower Ph range, that adapts better to coco growing, being 5.8 the average ph used, so the Ph range starts below it and end after it. 5.6-6.0 is usual in this school, but wider ranges are used, up to 5.3-6.3. This regime allows to get a balanced uptake of Ca and Mg, thus it not require aditional Ca/Mg as far as the nute profile used is balanced.
The first school is probably more widely used due its more similar to hydro growing used with other medias. But its more risky of getting a Ca accumulation and a general lock out when used in coco. Requires often flusing while the second school style not, and still the risk of having a "salt lock out", as growers of the first school often call the excess Ca, is way higher.
You not only used a Ph regime of the first school, but added CalMg instead of just Mg, and that lead to the lock out.
Once you have dropped the ph, it will take a while until plants recovering. Ca excess in the media is a slow fixing problem. As greenattick pointed out, ensure waterings are regular enough to keep the coco wet and abundant, so you do an small flush each time you water. Watering with some runoff is other technique that helps avoiding Ca to build up. Without often and abundant watering, its easier to have the problem.
Until fixing the problem, keep ph below 5.8. As it will difficulty Mg uptake, and you already has a deff of Mg due the excess Ca, treat the plants with foliar feeding with Epsom.
One just translates the parameters of general hydro growing and modify it a little to work fine in coco. It consist on using a ph range 5.8-6.2 and add Epsom Salts (mainly Magnesium Sulphate, MgSO4) to compensate for the higher percentage of Mg vs Ca uptaked on this regime.
The other uses a lower Ph range, that adapts better to coco growing, being 5.8 the average ph used, so the Ph range starts below it and end after it. 5.6-6.0 is usual in this school, but wider ranges are used, up to 5.3-6.3. This regime allows to get a balanced uptake of Ca and Mg, thus it not require aditional Ca/Mg as far as the nute profile used is balanced.
The first school is probably more widely used due its more similar to hydro growing used with other medias. But its more risky of getting a Ca accumulation and a general lock out when used in coco. Requires often flusing while the second school style not, and still the risk of having a "salt lock out", as growers of the first school often call the excess Ca, is way higher.
You not only used a Ph regime of the first school, but added CalMg instead of just Mg, and that lead to the lock out.
Once you have dropped the ph, it will take a while until plants recovering. Ca excess in the media is a slow fixing problem. As greenattick pointed out, ensure waterings are regular enough to keep the coco wet and abundant, so you do an small flush each time you water. Watering with some runoff is other technique that helps avoiding Ca to build up. Without often and abundant watering, its easier to have the problem.
Until fixing the problem, keep ph below 5.8. As it will difficulty Mg uptake, and you already has a deff of Mg due the excess Ca, treat the plants with foliar feeding with Epsom.
As the plant uses up the nutrients the ph rises.* Not enough food ph rises, to much food the ph drops. Water till run off everyday,measure your ph and ppm,adjust accordingly.* 5.5 - 6.2 ph is fine. The plant will let you know the ppm,take measurements.....mitsu
Holy Cow!
OK knna, I'm sorry but your giving people some wrong info.
You may have great results, because, you are right, pH is king. Keep that right and not too heavy of nutes and you're good. You're right about it being a Mg def and a possible K def.
The stuff about Ca being restricted at high pH is simply wrong. Ca is more readily absorbed at high pH. Mg starts to lock out at pH below 5.4. Ca locks out at low pH too. K can be deficient at any pH and may be affected by an antagonsim of Excess N, Ca or Mg. In this case not from Mg or Ca. Too much sodium can also reduce availability of K, Ca, Mg and that could be caused by the coco getting too dry and some of the salt ions rebonding into sodium chloride and being taken up instead of Potassium chloride. Cal mag deficiencies are always low pH related unless you're using insufficient nutes.
What's going on is the coco is drying out because of not watering daily and causing nute/salt concentration which in turn lowers the pH inside the root zone. Causing the Mg defs shown in the pic.
to the OP~ have you flushed and put them on a daily schedule already?
Last edited:
yes i flushed and now there getting fed daily
Holy Cow!
OK knna, I'm sorry but your giving people some wrong info.
You may have great results, because, you are right, pH is king. Keep that right and not too heavy of nutes and you're good. You're right about it being a Mg def and a possible K def.
The stuff about Ca being restricted at high pH is simply wrong. Ca is more readily absorbed at high pH. Mg starts to lock out at pH below 5.4. Ca locks out at low pH too. K can be deficient at any pH and may be affected by an antagonsim of Excess N, Ca or Mg. In this case not from Mg or Ca. Too much sodium can also reduce availability of K, Ca, Mg and that could be caused by the coco getting too dry and some of the salt ions rebonding into sodium chloride and being taken up instead of Potassium chloride. Cal mag deficiencies are always low pH related unless you're using insufficient nutes.
What's going on is the coco is drying out because of not watering daily and causing nute/salt concentration which in turn lowers the pH inside the root zone. Causing the Mg defs shown in the pic.
to the OP~ have you flushed and put them on a daily schedule already?
knna
Member
Hazy, Im glad you chime in to debate this issue.
Ive seem many times the same thing on the boards related with coco growing. You may be right, and my explanation of what is happennig is wrong.
As you pointed out, it works for me and for many people that I suggested this way of action. So I suppoused Im right, and its a mere coincidence that the suggested treatment works although the actual cause of the problem is different.
As we agree in the actual deffs showing, but disagree on what causes it, and treatment must be related to the cause I think having a good debate about it definitively worth
I think the cause is excess Ca in the medium, that lock out Mg uptake and difficulties K uptake.
In some way, you agree with that, as you say insufficient watering has caused build up of nutes on the media, raising its EC and dropping Ph, that in turn locks out Ca and Mg. I say it agrees partially with my explanation in the sense of Ca accumulation in the media.
And I agree with you in that not enough often watering has aggravated the problem (mi point) or created it (yours).
But Ca depends of water uptake for being absorbed. And its the element with the slower uptake rate. I think that if the cause is alone insufficient watering and ph of the media dropping so much, it should have let to a Ca defficiency too.
About Ca and Mg being locked out by low ph, its only true for soil. Things change on other medias, where that general rule must me matized. I have tried to find any accurate table of element uptake by Ph for coco, but I have been unable to find it. When I was starting growing I found this table:
This a simplified table, and as with any other resource on the net, accuracy is unkown. I would like to ask the author about the data that back it up, but I suppouse its not a random invention. The change in Ca uptake range is very significant. And notice many of the other change too, but only on the scale, not in the "position" within the table.
Anyway, I was aware of this being a simplified table that dont show at what ph uptake is higher or any reference about relative uptake.
So Ive looking for more reliable charts that shows the difference between ranges of absortion and solubility in soil and hydro. Coco is a almost inert media (at least, new one), as others hidro medias, but organic, as peat, having a very high CEC. I know CEC of the sustrate affects solubility (for example, if Ca++ ions are bonded to negative colloids, and there is many of them, likely bonding with PO4- ions is less probable.
Ive found some:
You can notice how Ca and P avalaibility changes between medias. P range is almost opposite for both. Its avalaibility starts to be good at 6.0 in soil, but its the end on the good range in soiless. Ca have a very wider uptake range in soiless than in soil. Although I was right with Ca being more avalaible below 5.8, difference is very small. It depends little of Ph, its uptaked well over ph5.
This chart is a little more clear for the soiless part:
I must admit that although I didnt state that Ca is bad absorbed at ph over 5.8, but that relative uptake of Ca/mg change, I was wrong. Although I have read it, I cant find any info supporting this change in the direction of the relative uptake between Ca and Mg.
On the other hand, insuffient watering and dropping of Ph should have let to Ca deff aswell.
In this situation, the advice of dropping ph has worked many times. So I think we have to find another explanation for this issue.
Maybe it may be explained by the continous add of CalMg, providing more Ca than the plant can uptake, so although there is not Ca deff, it has accumulated in the media and its locking out Mg and K.
Anyway, the treatment I suggest for this issue has been abundant and often waterings, hot temps, lower humidity (measures for increasing transpiration and water uptake) and lower ph. And it has worked many times. So maybe suggested for wrong reasons, but works. I still think there is an excess of Ca in the coco.
Ive seem many times the same thing on the boards related with coco growing. You may be right, and my explanation of what is happennig is wrong.
As you pointed out, it works for me and for many people that I suggested this way of action. So I suppoused Im right, and its a mere coincidence that the suggested treatment works although the actual cause of the problem is different.
As we agree in the actual deffs showing, but disagree on what causes it, and treatment must be related to the cause I think having a good debate about it definitively worth
I think the cause is excess Ca in the medium, that lock out Mg uptake and difficulties K uptake.
In some way, you agree with that, as you say insufficient watering has caused build up of nutes on the media, raising its EC and dropping Ph, that in turn locks out Ca and Mg. I say it agrees partially with my explanation in the sense of Ca accumulation in the media.
And I agree with you in that not enough often watering has aggravated the problem (mi point) or created it (yours).
But Ca depends of water uptake for being absorbed. And its the element with the slower uptake rate. I think that if the cause is alone insufficient watering and ph of the media dropping so much, it should have let to a Ca defficiency too.
About Ca and Mg being locked out by low ph, its only true for soil. Things change on other medias, where that general rule must me matized. I have tried to find any accurate table of element uptake by Ph for coco, but I have been unable to find it. When I was starting growing I found this table:
This a simplified table, and as with any other resource on the net, accuracy is unkown. I would like to ask the author about the data that back it up, but I suppouse its not a random invention. The change in Ca uptake range is very significant. And notice many of the other change too, but only on the scale, not in the "position" within the table.
Anyway, I was aware of this being a simplified table that dont show at what ph uptake is higher or any reference about relative uptake.
So Ive looking for more reliable charts that shows the difference between ranges of absortion and solubility in soil and hydro. Coco is a almost inert media (at least, new one), as others hidro medias, but organic, as peat, having a very high CEC. I know CEC of the sustrate affects solubility (for example, if Ca++ ions are bonded to negative colloids, and there is many of them, likely bonding with PO4- ions is less probable.
Ive found some:
You can notice how Ca and P avalaibility changes between medias. P range is almost opposite for both. Its avalaibility starts to be good at 6.0 in soil, but its the end on the good range in soiless. Ca have a very wider uptake range in soiless than in soil. Although I was right with Ca being more avalaible below 5.8, difference is very small. It depends little of Ph, its uptaked well over ph5.
This chart is a little more clear for the soiless part:
I must admit that although I didnt state that Ca is bad absorbed at ph over 5.8, but that relative uptake of Ca/mg change, I was wrong. Although I have read it, I cant find any info supporting this change in the direction of the relative uptake between Ca and Mg.
On the other hand, insuffient watering and dropping of Ph should have let to Ca deff aswell.
In this situation, the advice of dropping ph has worked many times. So I think we have to find another explanation for this issue.
Maybe it may be explained by the continous add of CalMg, providing more Ca than the plant can uptake, so although there is not Ca deff, it has accumulated in the media and its locking out Mg and K.
Anyway, the treatment I suggest for this issue has been abundant and often waterings, hot temps, lower humidity (measures for increasing transpiration and water uptake) and lower ph. And it has worked many times. So maybe suggested for wrong reasons, but works. I still think there is an excess of Ca in the coco.
Attachments
I think that first chart is not reliable.
I think the other ones, which are the standard ones that float around, are close, though not perfect. Coco's another thing too. I use the lucas formula modified to 6/9 for coco with a little magnesium sulphate. Sometimes i do add a little calcium. My water is rock hard and full of Calcium so I use gh's hardwater micro. My water's pH is 8+, but is brought down to about 5.8 with nutes. My runoff hovers at 6.2 pH. My plants look great, so I think the chart can only be a guide.
Truly though, if pH can be kept good(5.6-6.2) all should be good.
I think the other ones, which are the standard ones that float around, are close, though not perfect. Coco's another thing too. I use the lucas formula modified to 6/9 for coco with a little magnesium sulphate. Sometimes i do add a little calcium. My water is rock hard and full of Calcium so I use gh's hardwater micro. My water's pH is 8+, but is brought down to about 5.8 with nutes. My runoff hovers at 6.2 pH. My plants look great, so I think the chart can only be a guide.
Truly though, if pH can be kept good(5.6-6.2) all should be good.
ok so its been awhile since ive updated the status of my garden. I have done a bunch of research on the topic of watering and exactly what canna recommends as far as source water and i finally received an e-mail back from them stating that there nutrients are specifically designed to be used with tap water with an average ppm for 250. They also stated that they have done several studies of municipal tap water supplies and the all have sufficient amounts of calcium and mag. Also they stated that without that initial source of ca and mg in the water source that suplements have to be used but they specificly stated that use of cal-mag or cal-max contain additional trace elements, sometimes in excess. Like cal-mag plus containd iron and sulfur wich cause major problems when mixing with A&b by causing an array of nutrient lockouts and root zone ph instabillity. Also the great debate wheather to water everyday has been solved they say to water at 50% depletion whitch means not every day in the size pots we use. This is my first time using coco and i chose it for its ability to be re-used but there is definitely a learning curve to it, and trust me im learning, this crop has been severly stunted by my lack of knowledge and the time it took them to get me the facts but now I know and my next round is ganna be off the hook. Thanks for everyone's input it helped alot
E
EvilTwin
Mornin' AK,
Glad you're getting a handle on things. I went through all that several years ago when there weren't as many coco growers and not as much info available.
I wanted to suggest to you to stick with the same coco since differ brands have different grinds and that alters water holding. It comes from really fine which can almost get muddy if you water it too much vs the coarser grinds for hydro which can require multiple feedings daily...sort of like hydroton.
When you get around to re-using your coco...be sure to flush well and pre-charge with a mild nutrient solution. Canna does all that for you for the first run...but then it's on you to prepare it properly.
Also as it's aged and used a few times...then you can start getting some excess K issues. You can't re-use it forever but I've re-used 3 times with no difficulty.
Oh, awhile back you had asked about Epsom salt doses. Sounds like you may not need to use it, but if so, use around 1/4tsp/gal as a starting/maintenance dose and 2 or 3 times that if you have a deficiency.
Peace,
ET
Glad you're getting a handle on things. I went through all that several years ago when there weren't as many coco growers and not as much info available.
I wanted to suggest to you to stick with the same coco since differ brands have different grinds and that alters water holding. It comes from really fine which can almost get muddy if you water it too much vs the coarser grinds for hydro which can require multiple feedings daily...sort of like hydroton.
When you get around to re-using your coco...be sure to flush well and pre-charge with a mild nutrient solution. Canna does all that for you for the first run...but then it's on you to prepare it properly.
Also as it's aged and used a few times...then you can start getting some excess K issues. You can't re-use it forever but I've re-used 3 times with no difficulty.
Oh, awhile back you had asked about Epsom salt doses. Sounds like you may not need to use it, but if so, use around 1/4tsp/gal as a starting/maintenance dose and 2 or 3 times that if you have a deficiency.
Peace,
ET
C
Carl Carlson
water pH vs medium pH when growing in coco
water pH vs medium pH when growing in coco
I look at the range in irrigation water pH used by many successful growers using coco only. 5.5, 5.6-6.2, 5.8, 5.8-6.2, 5.3-6.3, etc. and ask how this is possible if water pH is so important?
Yes, pH is important, but it's not king in a coco grow. I'm convinced that people put way too much emphasis on the water pH because they assume coco is like rockwool, perlite or clay balls and the water pH can change the coco pH on the fly. And they confirm this by measuring the runoff immediately after feeding (back to that later). Part of the reason for the confusion is that because of it's other physical properties, coco can be used in hydro systems, but it is still much more like peat in terms of pH and EC mgmt. than it is like rockwool, perlite or clay balls. The Cation Exchange capacity of the latter three is much lower if anything (?).
I've found and think most other coco growers will agree that the pH of really good coco is very stable throughout a grow. I started out growing in coco only by keeping the fertigation water pH in a tight range - 5.6 -6.2. But than I did one grow where it was 5.8 the whole time and that worked out fine too.
I think the pH of runoff that is a direct result of feeding is higher than the pH of the water+nutes fed because there is an exchange of ions going on. To test the coco solution pH and EC or ppms, use the NCState pour through method. Instead of testing runoff, test with distilled or r.o. that is poured through after feeding with nutes to saturation.
water pH vs medium pH when growing in coco
I look at the range in irrigation water pH used by many successful growers using coco only. 5.5, 5.6-6.2, 5.8, 5.8-6.2, 5.3-6.3, etc. and ask how this is possible if water pH is so important?
Yes, pH is important, but it's not king in a coco grow. I'm convinced that people put way too much emphasis on the water pH because they assume coco is like rockwool, perlite or clay balls and the water pH can change the coco pH on the fly. And they confirm this by measuring the runoff immediately after feeding (back to that later). Part of the reason for the confusion is that because of it's other physical properties, coco can be used in hydro systems, but it is still much more like peat in terms of pH and EC mgmt. than it is like rockwool, perlite or clay balls. The Cation Exchange capacity of the latter three is much lower if anything (?).
I've found and think most other coco growers will agree that the pH of really good coco is very stable throughout a grow. I started out growing in coco only by keeping the fertigation water pH in a tight range - 5.6 -6.2. But than I did one grow where it was 5.8 the whole time and that worked out fine too.
I think the pH of runoff that is a direct result of feeding is higher than the pH of the water+nutes fed because there is an exchange of ions going on. To test the coco solution pH and EC or ppms, use the NCState pour through method. Instead of testing runoff, test with distilled or r.o. that is poured through after feeding with nutes to saturation.
G
guest1ab
boy I don't think I helped AK one bit. 
OrganicMonkey
Member
It looks like fertilizer burn, perhaps that plant doesn't require as many waterings/feedings. That is a large pot and I doubt that plant has rooted into it all that much. I'd test to see where she wilts at (just a tiny wilt), so you have a better indication of when she needs watering not feeding.
Coca does retain nutrients, water evaporates although people do get away with it but these usually aren't classic sativa's plants. That clone doesn't look like OG x Cheese, unless it's a very Thai OG.
I'd bet if the run off was tested, you would see the PPM higher than what you were adding. Plus coca holds water nicely, not always needing more moisture.
Coca does retain nutrients, water evaporates although people do get away with it but these usually aren't classic sativa's plants. That clone doesn't look like OG x Cheese, unless it's a very Thai OG.
I'd bet if the run off was tested, you would see the PPM higher than what you were adding. Plus coca holds water nicely, not always needing more moisture.
it looks like light bleaching to me. had a few leaves just recently that looked just like that. I found it was lights being to close.
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