Grim Reefer
DWC & LST
Oh when it comes to Weed, and autos i find i learn something new every day, especially when im growing or surfing the AFN.
Dutch Passion 4xABBs in a scrog under a GN MS0006 rebel
- Thread starter dirty budster
- Start date
South Syder
Quack Master!
Really enjoying this one. Keep it up man. 
I expected a learning curve switching to LED, I just didn't expect it to be this steep. I never really had to deal with any deficiencies before and especially not this early.
Thanks Lewb, ballache is the right word. I'm still struggling a bit with the Mg deficiency.
Really enjoying this one. Keep it up man.
Thanks man!
Grim Reefer
DWC & LST
I think its down to the plant as well as the LED. I got terrible cal/mg in my second grow and it was very early on in the veg stage under a hps. Im also aware of the LED bringing on cal/mg signs earlier than other lights.
Epson salts are better for treating a magnesium deficiency which it looks like you have. Also like others say dolomite lime is good to add to soil so definitely add some next time. Not too much but some is better than none.
As for how to fix your problems right now, Epson salt foliar feed man, get on it pronto. (Any pros feel free to chime in and tell me I'm wrong here.)
But if I were you I'd definitely start spray some plain water with Epson salts diluted in it every day, starting right now. Get your Epson salts from most places sell them, gardening stores, health stores. It's Magnesium Sulphate so it will correct Magnesium and Sulphur issues. Foliar feeding it works VERY quickly. Using it as a soil drench isn't recommended, I would just stick with foliar feeds, easier to not fk up.
Mix half a tea spoon with two litres of warm / hot water and shake it till all the salt crystals are properly dissolved. Spray your plant, soak the thing, especially the underside of the leaves where the somata are that's most important. Also make sure you do it when the temperatures aren't too hot, because if it's too hot the plants stomata close and it's almost pointless. Since you use LED's it's probably not an issue, but if you live in a warm country or use HPS it could be.
Spray them every single day with this solution for 6 days and on the 7th day spray her with plain clean water so she doesn't get a salt build up on her. Then resume spraying her with every 2-3 days with this solution after that as a preventative measure. Foliar feeding Epson salts is the best quickest way to fix a magnesium problem which to me anyway definitely looks like what you have.
Also I'd probably up the Cal-Mag to full strength while you're at it as someone else on here already recommended. Add dolomite lime to the soil next grow. Have your Epson salts to hand and next time you grow as soon as you see yellowing between the viens (but the veins are still dark green) then you know it's magnesium / epsom salts foliar spray time.
Good luck man. Keep going they will bounce back as long as you get on fixing this today. I'm subscribing and will watch your grow. Thanks man.
edit : Couple of extra points. When you're foliar feeding be really careful not to spray your electrics. Because you're spraying the underside of the leaves especially it's easy to spray up onto your lights. What I do is I use a green coloured head lamp and I go in an hour after the lights turn off and spray them then. Or lights all the way up and spray them.
Secondly if you want to add extra power to your foliar feed adding a wetting agent / a surfactant helps. It breaks water surface tension (stops water beading up) and allows a more even wet coverage. Some people use a couple of drops of non-toxic dish washing soap, but I personally just bought Wet Betty from Advanced Nutrients for about $25 for one litre. You only need 1-2ml per litre so it's going to last me years. Or if you find some Yucca Extract that works too but I've never used it or dishwashing soap before so I can't comment or recommend. Anyway I'm sure it doesn't reaaally matter that much. Just foliar spray with Epson Salts solution now and worry about this surfactant issue later, it's no way near as important as foliar feeding epson salts asap. If you had have been feeding them with epson salts and more cal-mag a week ago when this started they'd be green and a couple of inchers taller by now. Ah well, that's the way it goes your next grow will be all the better for it. Keep on keeping on man. In a couple of weeks time they'll be back to looking green and healthy again.
As for how to fix your problems right now, Epson salt foliar feed man, get on it pronto. (Any pros feel free to chime in and tell me I'm wrong here.)
But if I were you I'd definitely start spray some plain water with Epson salts diluted in it every day, starting right now. Get your Epson salts from most places sell them, gardening stores, health stores. It's Magnesium Sulphate so it will correct Magnesium and Sulphur issues. Foliar feeding it works VERY quickly. Using it as a soil drench isn't recommended, I would just stick with foliar feeds, easier to not fk up.
Mix half a tea spoon with two litres of warm / hot water and shake it till all the salt crystals are properly dissolved. Spray your plant, soak the thing, especially the underside of the leaves where the somata are that's most important. Also make sure you do it when the temperatures aren't too hot, because if it's too hot the plants stomata close and it's almost pointless. Since you use LED's it's probably not an issue, but if you live in a warm country or use HPS it could be.
Spray them every single day with this solution for 6 days and on the 7th day spray her with plain clean water so she doesn't get a salt build up on her. Then resume spraying her with every 2-3 days with this solution after that as a preventative measure. Foliar feeding Epson salts is the best quickest way to fix a magnesium problem which to me anyway definitely looks like what you have.
Also I'd probably up the Cal-Mag to full strength while you're at it as someone else on here already recommended. Add dolomite lime to the soil next grow. Have your Epson salts to hand and next time you grow as soon as you see yellowing between the viens (but the veins are still dark green) then you know it's magnesium / epsom salts foliar spray time.
Good luck man. Keep going they will bounce back as long as you get on fixing this today. I'm subscribing and will watch your grow. Thanks man.
edit : Couple of extra points. When you're foliar feeding be really careful not to spray your electrics. Because you're spraying the underside of the leaves especially it's easy to spray up onto your lights. What I do is I use a green coloured head lamp and I go in an hour after the lights turn off and spray them then. Or lights all the way up and spray them.
Secondly if you want to add extra power to your foliar feed adding a wetting agent / a surfactant helps. It breaks water surface tension (stops water beading up) and allows a more even wet coverage. Some people use a couple of drops of non-toxic dish washing soap, but I personally just bought Wet Betty from Advanced Nutrients for about $25 for one litre. You only need 1-2ml per litre so it's going to last me years. Or if you find some Yucca Extract that works too but I've never used it or dishwashing soap before so I can't comment or recommend. Anyway I'm sure it doesn't reaaally matter that much. Just foliar spray with Epson Salts solution now and worry about this surfactant issue later, it's no way near as important as foliar feeding epson salts asap. If you had have been feeding them with epson salts and more cal-mag a week ago when this started they'd be green and a couple of inchers taller by now. Ah well, that's the way it goes your next grow will be all the better for it. Keep on keeping on man. In a couple of weeks time they'll be back to looking green and healthy again.
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Grim Reefer
DWC & LST
Dont forget Happy Hort, most of the time when you have a mg diff it will lock out calcium as well so just make sure your feeding cal as well as mg.
Yip I agree with ya Briain
Hence he should up the Cal-Mag feed. I see in day 10 / 12 photos calcium deficiency started, that's when cal-mag should have been upped and the problem wouldn't be so bad right now.
To fix the problem up the cal-mag feed and supplement with Epson salt solution foliar spray to quickly fix the magnesium deficiency which is the main issue right now. By the time the Epsom salts foliar is working the cal-mag will start kicking in. Then the plant will be back to growing health shoots and leaves again. The grow can still be totally saved. Maybe lose a few grams but definitely savable. I know with photo strains I wouldn't be so worried, but with no real world experience with autos I don't know
Hence he should up the Cal-Mag feed. I see in day 10 / 12 photos calcium deficiency started, that's when cal-mag should have been upped and the problem wouldn't be so bad right now.
To fix the problem up the cal-mag feed and supplement with Epson salt solution foliar spray to quickly fix the magnesium deficiency which is the main issue right now. By the time the Epsom salts foliar is working the cal-mag will start kicking in. Then the plant will be back to growing health shoots and leaves again. The grow can still be totally saved. Maybe lose a few grams but definitely savable. I know with photo strains I wouldn't be so worried, but with no real world experience with autos I don't know
That's a good point Briain, I went back and looked at photos from my previous grows and I think I always had a slight Mg def that was resolved as soon as I started adding nutes.
Thanks for the info Happy, I will keep that in mind for my next grow. I did try foliar feeding with Epsom salt but it left some undissolved crystals on the leaves even though I mixed it in warm water. For the past 4-5 days I've been foliar feeding with cal-mag with a tiny amount of detergent. That seemed to help a bit.
Yip I agree with ya Briain
Hence he should up the Cal-Mag feed. I see in day 10 / 12 photos calcium deficiency started, that's when cal-mag should have been upped and the problem wouldn't be so bad right now.
To fix the problem up the cal-mag feed and supplement with Epson salt solution foliar spray to quickly fix the magnesium deficiency which is the main issue right now. By the time the Epsom salts foliar is working the cal-mag will start kicking in. Then the plant will be back to growing health shoots and leaves again. The grow can still be totally saved. Maybe lose a few grams but definitely savable. I know with photo strains I wouldn't be so worried, but with no real world experience with autos I don't know
Yes you're right, I completely missed it in the early days. I never used cal-mag before so I wasn't sure if it could be added at full strength that early. I'm not sure if that's the only thing that went wrong as also the plants with less severe Mg def have been showing poor growth. I'm wondering if I watered them too often in the seedling stage as I have seen now how long it takes for the pots to dry out. On top of that I also watered them too early trying to get more cal-mag into the soil. I'm wondering if that has caused poor root development.
Over the past days I've let the pots dry out properly and I noticed that there was almost 0 growth during this time as you can see in the pictures. It's now been 6 days since the last watering and they're dry enough for another feeding. I will water them with root stim, 2/5 veg nutes and a full dose of cal-mag. I'm hoping that will help them recover a bit. I'm not sure to what extent the grow can be saved as they're already looking ready to flower. If it weren't for the fact that I wanted to squeeze in another grow before August I might have pulled them and started over.
Thanks Briain and Happy for the help, it's much appreciated.
Day 28
Day 30
As you can see #1 especially has really taken a beating. It also looks like it has a nitrogen deficiency. I'm not expecting too much from this one.
It looks like it's getting ready to go into full flower already.
IF you're getting undissolved crystals you need to use hotter water to get them to dissolve. Maybe mix them in a large glass with some almost boiled water first. I never really had issues with it and the epsom salts foliar feed has saved my ass before believe me. Your magnesium issue hasn't gotten any better in the past two days which is why I'm suggesting rethinking not using the epsom salts foliar. Read up about it on the net if you're unsure you'll see loads of people reitterate what I'm saying. Also I think a plant can have slow / stunted growth even with a mild nutrient deficiency, it doesn't have to have a severe deficiency in order to have slower growth. But that being said could definitely be right about another issue in the root zone.
Would you consider going hydroponic next time? I find it's actually easier than dirt because I can read the numbers and correct issues quicker in hydro than in dirt. You could do something as simple as a dripper system or a flood and drain. One of my first attempts at hydroponics was a simple flood and drain system I built myself and I had a dirt plant next to it (they were my mother plants) and the hydro one grew massive compared to the dirt one. They really grow a lot quicker. If not then you could add more perlite to the dirt to aid aeration and use air pots because as you probably know roots don't die from too much water but from lack of air / suffocation. You can also put an ]airdome at the bottom of your pot or an airstone to help with aeration and avoid any potential root problems.
Finally I'm not sure if 2/5 is enough I would be giving them a higher dose myself. I'd be giving them at least half feed if not more since they're deficient, plus a full feed of cal-mag and epsom foliar feed as cal-mag foliar isn't helping fast enough. Finally I'm not sure if you're base nutes are good enough, I've no experience using them. I've used lots of nutrients and since I use R/O water really the only nutes that seem good enough for me with my R/O water are Advanced Nutrients as it has a high level of secondary and micro nutrients. I still have to add cal-mag because I've been growing in coco (and Advanced Nutrients don't have a coco nutrients range out at least in europe still) but just at half strength for most of the time. I don't use LEDs (yet though) so may probably run them at full strength after a couple of weeks with LEDs possibly. Especially after watching this grow. Scary stuff.
Would you consider going hydroponic next time? I find it's actually easier than dirt because I can read the numbers and correct issues quicker in hydro than in dirt. You could do something as simple as a dripper system or a flood and drain. One of my first attempts at hydroponics was a simple flood and drain system I built myself and I had a dirt plant next to it (they were my mother plants) and the hydro one grew massive compared to the dirt one. They really grow a lot quicker. If not then you could add more perlite to the dirt to aid aeration and use air pots because as you probably know roots don't die from too much water but from lack of air / suffocation. You can also put an ]airdome at the bottom of your pot or an airstone to help with aeration and avoid any potential root problems.
Finally I'm not sure if 2/5 is enough I would be giving them a higher dose myself. I'd be giving them at least half feed if not more since they're deficient, plus a full feed of cal-mag and epsom foliar feed as cal-mag foliar isn't helping fast enough. Finally I'm not sure if you're base nutes are good enough, I've no experience using them. I've used lots of nutrients and since I use R/O water really the only nutes that seem good enough for me with my R/O water are Advanced Nutrients as it has a high level of secondary and micro nutrients. I still have to add cal-mag because I've been growing in coco (and Advanced Nutrients don't have a coco nutrients range out at least in europe still) but just at half strength for most of the time. I don't use LEDs (yet though) so may probably run them at full strength after a couple of weeks with LEDs possibly. Especially after watching this grow. Scary stuff.
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