Yellowing leaves!

mastergreenerey · Oct 23, 2020

Hi guys,

Just transplanted 3 and half week clones from 12l into 20l pots. Using plain coco. I gave them a good soaking with nute solution after transplant, and i fed them as normal the following day 2l each.

I have 2 wedding cake 2 alien cookies.
Alien cookies have always been slower than WC not sure why seemed to be showing mag def after a week of having them upped nutes and they got better. After transplant however i have noticed a few yellowing leaves on only alien cookies. Transplant went smooth as ever didnt stress much at all so not sure if its another mag def i have upped cal mag in todays feed. Can anyone tell me what this could possibly be? Pics below

mastergreenerey · Oct 24, 2020

Guys yellowing leaves now developing brown spots and curling upwards??? Helppp

013 · Oct 26, 2020

Straight up... I suck at coco, but let’s get you bumped back up top for the others to see this. Have the symptoms gotten better or worse since you posted this on Saturday?

potassium deficiency maybe?

please wait to see what other replies come in.

mastergreenerey · Oct 26, 2020

013 said:
Straight up... I suck at coco, but let’s get you bumped back up top for the others to see this. Have the symptoms gotten better or worse since you posted this on Saturday?

potassium deficiency maybe?

please wait to see what other replies come in.

I am thinking potassium def myself and i feel as if its getting worse. Curling leaves which are yellowing at tips. I have upped AnB nutes last 2 feeds

013 · Oct 26, 2020

Do you feed to runoff? What strength is your nute solution?

mastergreenerey · Oct 26, 2020

Yeah been getting around 20 to 15% runoff. Last nute solution 11.5ml per 10l AandB, calmag 9ml per 10l, rhizo 10ml per 10l. Feeding 2l each per day

013 · Oct 26, 2020

Roger that! My understanding is since it’s coco it should be fed 1/4 strength nutes and has to be fed or fertigated every day or 2 X per day.

mastergreenerey · Oct 26, 2020

All my measurents are around 1/4 strength so not sure what else it could be, i normally feed 2l everyday should i maybe feed less more often?

013 · Oct 26, 2020

I’m soil grower so not my area, but my understanding is that once a plant gets bigger most go to 2 X per day and later in flower some do 3 X per day. Hopefully one of the knowledgable hydro growers will drop in

PE636 · Oct 26, 2020

I find it hard to believe you're getting 15-20 percent runoff by giving 2L to a 20L container.. (side note that's an awfully big container in the coco world.. I'd recommend 3 gallon/11L fabric pots for beginning coco growers). Not sure where this 1/4 strength nutes rule for coco ever came from even though it seems to get repeated a lot around here.... I would suspect not enough of your main nutrients and far too much calmag. Too much calcium will lock out potassium. Personally I'd drop the calmag completely unless the plant shows that it needs more than its getting from the base nutrients.. You need to get substantial runoff pretty regularly(daily) , the plant doesn't take up everything and the leftovers will build up over time and throw off the ratios.. I see no mention of ph.. You need to adjust the ph of the nutrient solution to between 5.8 and 6.2. I aim for 6.0 on mine. Hope this helps.

013 · Oct 26, 2020

Awwe shit - you are right PE636.... totally my bad - the 25% strength is for hempy or Dutch buckets.

See what I mean MasterGreenerey... I suck at all forms of hydro! I jumped in here mainly because your question sat open since Saturday

mastergreenerey · Oct 26, 2020

PE636 said:
I find it hard to believe you're getting 15-20 percent runoff by giving 2L to a 20L container.. (side note that's an awfully big container in the coco world.. I'd recommend 3 gallon/11L fabric pots for beginning coco growers). Not sure where this 1/4 strength nutes rule for coco ever came from even though it seems to get repeated a lot around here.... I would suspect not enough of your main nutrients and far too much calmag. Too much calcium will lock out potassium. Personally I'd drop the calmag completely unless the plant shows that it needs more than its getting from the base nutrients.. You need to get substantial runoff pretty regularly(daily) , the plant doesn't take up everything and the leftovers will build up over time and throw off the ratios.. I see no mention of ph.. You need to adjust the ph of the nutrient solution to between 5.8 and 6.2. I aim for 6.0 on mine. Hope this helps.

Thanks for reply, I had them in 12l and transplanted about 5 days ago.. 2 of 4 plants not showing any issues.. how many litres would u give to 20l? Ill drop calmag tomorrows feed and at what strenth would u recommend A n B?i normally ph to 5.8 and i also callibrated PH pen today was showing 7.5 in ph7 buffer. But sorted now. My temps hover between 23 and 27 with lights on and around 18-20 lights off. RH is between 50 and 60%.

PE636 · Oct 27, 2020

mastergreenerey said:
Thanks for reply, I had them in 12l and transplanted about 5 days ago.. 2 of 4 plants not showing any issues.. how many litres would u give to 20l? Ill drop calmag tomorrows feed and at what strenth would u recommend A n B?i normally ph to 5.8 and i also callibrated PH pen today was showing 7.5 in ph7 buffer. But sorted now. My temps hover between 23 and 27 with lights on and around 18-20 lights off. RH is between 50 and 60%.

What brand are your nutrients and what are the n-p-k numbers on the bottles? What do their instructions say? I'd probably be aiming around half of their recommended full
strength for now... What is the Rhizo you mentioned?
Are you using well water /municipal water /RO or what? Do you know it's starting ppm or anything about it? Most other than RO has some mineral content to begin with (read some calmag already present). You'll have to watch the overall green colour of the plants and clues like burnt tips or clawing leaf tips to figure out the exact right dose. Wish I could be more specific but it's one of those half science half art deals, and even individual plants can be a little different in what they like.
So if your ph pen was saying 5.8 you were really feeding around 5.3 correct? That in itself is a bit of an issue, definitely keep your pen calibrated. Not sure what pen you have but if your budget allows you might consider picking up one of the more expensive pens, I use an Apera PH60 which is by far more stable and reliable than some of the cheap 20 dollar ones I've had before..
I'd be inclined to give them a very slow and thorough rinse with the half strength nutes to wash out any weirdness you've got going on, maybe 5 or 6L each to get some good runoff... How much you'll need daily going forward will depend on how much the plants are drinking /is evaporating.. Water slowly, don't just dump it in. And keep going until you get some good steady dripping. You can't really use too much as the coco will only hold so much, and the extra will drain out. For example mine in 3g/11L pots are getting 4L daily per pot to get a maybe a liter each of runoff. Ocasionally I'll use less if I am rushed but the next day is a full amount with lots of runoff again to clean things out. Be sure to elevate the pots somehow for good drainage if you're not already, don't let them sit in the runoff.

mastergreenerey · Oct 27, 2020

PE636 said:
What brand are your nutrients and what are the n-p-k numbers on the bottles? What do their instructions say? I'd probably be aiming around half of their recommended full
strength for now... What is the Rhizo you mentioned?
Are you using well water /municipal water /RO or what? Do you know it's starting ppm or anything about it? Most other than RO has some mineral content to begin with (read some calmag already present). You'll have to watch the overall green colour of the plants and clues like burnt tips or clawing leaf tips to figure out the exact right dose. Wish I could be more specific but it's one of those half science half art deals, and even individual plants can be a little different in what they like.
So if your ph pen was saying 5.8 you were really feeding around 5.3 correct? That in itself is a bit of an issue, definitely keep your pen calibrated. Not sure what pen you have but if your budget allows you might consider picking up one of the more expensive pens, I use an Apera PH60 which is by far more stable and reliable than some of the cheap 20 dollar ones I've had before..
I'd be inclined to give them a very slow and thorough rinse with the half strength nutes to wash out any weirdness you've got going on, maybe 5 or 6L each to get some good runoff... How much you'll need daily going forward will depend on how much the plants are drinking /is evaporating.. Water slowly, don't just dump it in. And keep going until you get some good steady dripping. You can't really use too much as the coco will only hold so much, and the extra will drain out. For example mine in 3g/11L pots are getting 4L daily per pot to get a maybe a liter each of runoff. Ocasionally I'll use less if I am rushed but the next day is a full amount with lots of runoff again to clean things out. Be sure to elevate the pots somehow for good drainage if you're not already, don't let them sit in the runoff.

So im using canna brand A B- bottle says 40ml per 10l Canna rhizotonic bottle says 40ml per 10l , and shogun calmag bottle says 1ml per litre.NPK i will check.Im using normal tap water no ppm meter but i have checked and we have soft water. Ph pen was showing 5.8 but in reality was 6.3 have not calibrated for over a month so will do more regularly. When u say rinse with half strength are we talking bottle recommendations or what i am currently giving? Im going to brew todays feed in a few hours so ill prepare for 5l each should i not add calmag in this feed? Or small amount?
Thanks for the help btw.

PE636 · Oct 27, 2020

mastergreenerey said:
So im using canna brand A B- bottle says 40ml per 10l Canna rhizotonic bottle says 40ml per 10l , and shogun calmag bottle says 1ml per litre.NPK i will check.Im using normal tap water no ppm meter but i have checked and we have soft water. Ph pen was showing 5.8 but in reality was 6.3 have not calibrated for over a month so will do more regularly. When u say rinse with half strength are we talking bottle recommendations or what i am currently giving? Im going to brew todays feed in a few hours so ill prepare for 5l each should i not add calmag in this feed? Or small amount?
Thanks for the help btw.

I'm confused. If the pen was saying 7.5 in the 7 solution it's reading high. So if it was saying 5.8 it was really 5.3 no?... I meant half of what the bottle says so 20ml of each part in 10L water. I'd skip the calmag, I suspect your water and the base nutrients have plenty to begin with. Best to keep it simple when having issues, more is not always better. I'd even skip the rhizotonic for now or just use a tiny bit if you can't resist. Their website says the maintenance dose of rhizo is only 5ml per 10L water.

mastergreenerey · Oct 27, 2020

PE636 said:
I'm confused. If the pen was saying 7.5 in the 7 solution it's reading high. So if it was saying 5.8 it was really 5.3 no?... I meant half of what the bottle says so 20ml of each part in 10L water. I'd skip the calmag, I suspect your water and the base nutrients have plenty to begin with. Best to keep it simple when having issues, more is not always better. I'd even skip the rhizotonic for now or just use a tiny bit if you can't resist. Their website says the maintenance dose of rhizo is only 5ml per 10L water.

Sorry your right its 5.3 my mistake. Thanks i have just done todays feed just under half strength and only 5ml rhizo in 16l. My rhizo on bottle says 40ml per 10l . And see below pics for NPK values