Leaves Turning Yellow: Need Advice

[DarkEagle]

First time grower here.

Plants are autoflowers and are in week 5 of 8. Soil is Pro-Mix Organic. Light is a 600W LED and is 18" above plants. Temperature in tent is 75F and humidity is 50. I gave them only water for the first 4 weeks. At the beginning of week 5 I added in 1/8 tsp per gallon of KoolBloom Dry Ripener (half of the recommended dose). 3 days later, yellow leaves began appearing. What could be the cause and what do I do? Thanks.

 

[Barney86]

Don't worry about the bottom stuff mate that's perfectly normal. The higher up stuff might be a cause for concern but need some non blurple pics to see what it is first.

 

[DarkEagle]

Don't worry about the bottom stuff mate that's perfectly normal. The higher up stuff might be a cause for concern but need some non blurple pics to see what it is first.

Here they are in natural light.

 

[Barney86]

Ah yeah looks a bit worse in natural light. It's N def mate. Theyve used all the nitrogen that came with the soil and there's non in the bloom supplement.
The plant will just start eating every leave like that now. If it was just at the bottom it's be normal but you don't want it further up the plant.
You've got 2 options that I can see.
No1, add nitrogen. Which at this stage of the game you don't wanna be doing really. I don't know how you'd go about it in organics iether.
No2 wait it out and hope the plants don't eat themselves before the buds fatten up.
Not an extremely helpful prognosis but because your going organic you can't just add something in.
@Emilya might know something I don't about it though. Seems to know her soil better than most

 

[bluter]

@Emilya might know something I don't about it though. Seems to know her soil better than most

^ this right here. barney pretty much has it sussed. wish i could add something.

 

[Emilya Green]

definitely a macro nutrient deficiency, and one of the mobile elements, since it is starting at the bottom and progressing upwards. Plants do not stop needing nitrogen even while in flower, so they could definitely use some and probably more of the flowering nutes besides.

First time grower here.

Hi @DarkEagle and welcome to the forum!
Plants are autoflowers and are in week 5 of 8. Soil is Pro-Mix Organic. Light is a 600W LED and is 18" above plants. Temperature in tent is 75F and humidity is 50. I gave them only water for the first 4 weeks. At the beginning of week 5 I added in 1/8 tsp per gallon of KoolBloom Dry Ripener (half of the recommended dose). 3 days later, yellow leaves began appearing. What could be the cause and what do I do? Thanks.

First, your plants are not 3 weeks from the end... that 8 weeks is more than likely the time while flowering... and I am guessing that your plants vegged for around 4 or 5 weeks of that. Actually, you are in the first or second week of flowering, and have 5 or 6 left to go.
Since your plants have now entered flowering mode, their nutritional needs have changed, although it was not yet appropriate to give finishing nutes, flowering nutes would be more appropriate. Regarding nutes, it sounds like someone told you that Promix Organic was a water only soil. It is not a super soil, nor is it a mineral rich soil that has everything in it that our plants could need... it is just a typical flower and vegetable potting soil. There are not enough organics in that soil to sustain our plants all the way through bloom. You will need to supply nutrients to finish out this grow, and as your plants are showing you, they are starting to starve due to a lack of several of the 17 elements needed to grow our weed. If your goal is to stay totally organic, let me suggest General Organics and their fine line of nutrients such as the GO Go Box, but if you would rather go more conventional, there are many synthetic nutes available for you to use, both expensive and economical.

 

[DarkEagle]

definitely a macro nutrient deficiency, and one of the mobile elements, since it is starting at the bottom and progressing upwards. Plants do not stop needing nitrogen even while in flower, so they could definitely use some and probably more of the flowering nutes besides.


First, your plants are not 3 weeks from the end... that 8 weeks is more than likely the time while flowering... and I am guessing that your plants vegged for around 4 or 5 weeks of that. Actually, you are in the first or second week of flowering, and have 5 or 6 left to go.
Since your plants have now entered flowering mode, their nutritional needs have changed, although it was not yet appropriate to give finishing nutes, flowering nutes would be more appropriate. Regarding nutes, it sounds like someone told you that Promix Organic was a water only soil. It is not a super soil, nor is it a mineral rich soil that has everything in it that our plants could need... it is just a typical flower and vegetable potting soil. There are not enough organics in that soil to sustain our plants all the way through bloom. You will need to supply nutrients to finish out this grow, and as your plants are showing you, they are starting to starve due to a lack of several of the 17 elements needed to grow our weed. If your goal is to stay totally organic, let me suggest General Organics and their fine line of nutrients such as the GO Go Box, but if you would rather go more conventional, there are many synthetic nutes available for you to use, both expensive and economical.

What would you recommend as an economical option?

 

[Emilya Green]

What would you recommend as an economical option?

Jack's Classic Dynamic Duo 20-20-20 & 10-30-20. This wont be organic, but for $20 you can get enough fertilizer to last you for a year. Growing pot does not have to be expensive.

 

[DarkEagle]

That particular brand doesn't seem to be available in Canada. I assume I should just look for something with the equivalent NPK numbers?

 

[Barney86]

For cheap bottled nutes I'd check out 'ionic'.
I've been using there stuff at various points for various reasons and I'm that impressed that I'm giving up my very expensive dutch pro and switching over.
1 part veg, 1 part bloom, 1 part PK booster.
The hydro version is any way. No idea what the soil version is but they're as cheap as bottled nutes reliably get and the results are awesome!

 

[Emilya Green]

That particular brand doesn't seem to be available in Canada. I assume I should just look for something with the equivalent NPK numbers?

Canada needs to fix their import laws... that is ridiculous. What could possibly be harmful about the cheapest commercial grade nutrients known to man?
Come as close as you can and don't get sucked into the hydro scam... you are growing in soil, don't compromise on some line of nutes that isn't made for soil.

 

[DarkEagle]

Thanks for all your help. This is what I ended up buying: CIL All Purpose Plant Food. Now, should I wait until they need watering again (they were watered yesterday) or feed them right away?

 

[Emilya Green]

always treat the most prominent problem... and that is starvation in this case. This time only , water early just to get as many nutes working as possible and then go back to waiting for them to dry out a little, but not much. When you are in flower, after stretch, it is time to water a lot more often, trying to see how much water you can get them to take. I would give nutes twice in a row, and then go to every other time. Be sure to pH to 6.3.

 

[DarkEagle]

Here is what they're looking like at day 68. Should I harvest now or give them another week? Thanks.

 

[Emilya Green]

68 is just a number... what do the trichomes look like? The lack of new white pistils makes me think that they might be done... but it is all about the trichomes.

 

[DarkEagle]

What exactly am I looking for Emilya? What should the trichomes look like?

 

[Emilya Green]

Pictures on when to harvest - Trichome colours