Sour crack leaves yellowing

andy s said:

yellowing between the veins are also a sign of a calmag def sometimes a ph flux too

Click to expand...

Yellowing of the lower leaves is more an indication of low N or Mg than Ca. If it is low Mg then CalMag is going to help for sure. If you know that your soil has lots of Ca in it from dolomitic lime or horticultural Gypsum etc then adding more Ca with the CalMag can bring on it's own problems with locking out Mg, K, Fe and Mn, (Manganese). So if it is low Mg because it's already locked out then CalMag will just make it worse. What you want is good old Epsom Salts. A tsp in a liter of water foliar sprayed on will help fix it quick and it can be added to the soil at the same rate. No Ca but some sulfur which is great for bud and resin development. The "secret ingredient" in bloom boosters. Hard to OD your plants on S too.

This is one of the best deficiency charts I've found tho still falls short of what I'd consider complete but that's what grow bibles are for right? Lots of clues around each picture of a plant that can lead you to a better diagnosis of what's ailing your plants.



I found a great spot to download FREE POT BOOKS. I downloaded a grow bible first and got lots more. Books look great and complete like the real ones I have here. No web site but just a page of links. Just right click on what you want and then "Save Link As" to download so they don't open first as some are 50+ megs. They got lots. Enjoy.

OldMedUser said:

I've had problems for years with crispy leaves usually starting around week 4 or 5 in flower and sometimes progressing into the tiny bud leaves. Thought it was due to overfeeding N so got 3 part nutes to better control N levels but still had problems. My last grow I just lowered all nutes by half and the plants grew great and had soft leaves as tehy yellowed near the end. Growing in a 50:50 mix of ProMix HP and ProMix potting soil that has organic nutes added. Feeding 3-part AN nutes at lower levels.

RH in my room is often below 20% during the winter and adding with humidifier doesn't help much as my controller kicks in the fan when the heat goes up and all the moist air gets blown out. Would have to have lots of moisture in incoming air to maintain proper RH steady and that would be hard to do. Or run sealed room with CO2 and that's hard to do with such limited funds.

So just going to run lower PPMs for now on. Starting DWC tubs soon and will be experimenting with various levels but likely 500 - 600ppm max where I would go up to 1400 depending on strain. I've done DWC in tubs since 2001 so got all the other bugs worked out.

Did you try bending leaves to see if they broke where they were brown?

Click to expand...

I’m having low humidity problems this year that I don’t remember in recent years are you in uk too? I have been advised to buy a good humidifier for around 500 pounds that can accommodate my setup smaller ones available try maplins they got good reviews. When you got low humidity your plants will suck up extra moisture to try compensate and if your feeding nutes then extra gets sucked up too resulting in nute burn and brown crispy leaves. I have been waiting to flip to flower for a couple weeks now but they just ain’t happy at all and they are beasts already but growth has slowed badly. 2 months ago I suffered some mold for the first time ever in 10 years humidity was so high it affected my biggest buds only so wasn’t so bad as there was minimal waste.but compared to now we got no humidty it’s fucking everyone who ain’t prepared for it in uk right now we got a dry winter it ain’t just you brother

Jimmy the vest uk said:

I’m having low humidity problems this year that I don’t remember in recent years are you in uk too? I have been advised to buy a good humidifier for around 500 pounds that can accommodate my setup smaller ones available try maplins they got good reviews. When you got low humidity your plants will suck up extra moisture to try compensate and if your feeding nutes then extra gets sucked up too resulting in nute burn and brown crispy leaves. I have been waiting to flip to flower for a couple weeks now but they just ain’t happy at all and they are beasts already but growth has slowed badly. 2 months ago I suffered some mold for the first time ever in 10 years humidity was so high it affected my biggest buds only so wasn’t so bad as there was minimal waste.but compared to now we got no humidty it’s fucking everyone who ain’t prepared for it in uk right now we got a dry winter it ain’t just you brother

Click to expand...

It ain’t just you I got the brown crispers popping up too for first time. It’s about lowering nute dose and maybe suffering a low yield or get a humidifier and finish your problems

Jimmy the vest uk said:

It ain’t just you I got the brown crispers popping up too for first time. It’s about lowering nute dose and maybe suffering a low yield or get a humidifier and finish your problems

Click to expand...

Just read back I ain’t teaching you nothing you already said it my bad sorry bro

Jimmy the vest uk said:

It ain’t just you I got the brown crispers popping up too for first time. It’s about lowering nute dose and maybe suffering a low yield or get a humidifier and finish your problems

Click to expand...

You don't get less nutes to your plant by running much lower PPMs because the plant is drawing more of a lower concentration up with all the extra water that equals out to what it should be getting if the RH was at it's proper level. Just have to adjust for the season. AS teh outdoor RH goes up so will teh grow room RH so you want to increase the PPM as transpiration slows. Then lower ppm as the RH goes down and the plants transpire faster. A bit of a balancing act but not all that hard to do.

I'm in northern Alberta around the 60th parallel. Dry as a popcorn fart up here even in the summer.

Jimmy the vest uk said:

Just read back I ain’t teaching you nothing you already said it my bad sorry bro

Click to expand...

No problem. I go off half-cocked sometimes too.

Anothermeduser said:

I said what i think, only ever speak out of experience, alls good.

Click to expand...

right but i didnt say you were wrong my man. just stated in case you didnt know. it seems like when someone has a bad leaf, there literally can be 4 or 5 different reason as to why it looks tht way but only one matters lol you just gotta find which one. one thing i hate about having issues growing pot is just that. you have an issue and youre torn bc it could be this or tht bc it shows the same symptoms lol so once again wasnt tryna call you out just threw a lil your way to add to what you said

andy s said:

right but i didnt say you were wrong my man. just stated in case you didnt know. it seems like when someone has a bad leaf, there literally can be 4 or 5 different reason as to why it looks tht way but only one matters lol you just gotta find which one. one thing i hate about having issues growing pot is just that. you have an issue and youre torn bc it could be this or tht bc it shows the same symptoms lol so once again wasnt tryna call you out just threw a lil your way to add to what you said

Click to expand...

Thank you sir. I am a life long vetran of the war on drugs, been a front line soldier my whole life, i have grown thousands of plants and #.. not many questions left. I have dealt with this problem succesfully and not by backing off. Just sharing , nobody thinks shit of my opinion and that fine..