HELP!! New growth tips yellowing

[Educatedbystoned]

I’m using a szhlux 400w light at 4 feet distance,
Ph water to 6.0-6.4
No nutrients feed yet
Soil-> recipe 420 topped with happy frog soil

What could the yellow be? Do they need nutrients about now? They sprouted 7/27/24

 

[ArtfulCodger]

The yellow tips look like a touch of minor nute burn, but I wouldn't worry about it. You might have caught a hot bag of Happy Frog. The plants are looking over-watered (speed bumps and thickness of the leaves), and a little over-lit (edge curl), so I might back off the watering frequency and light intensity a bit. The need for feeding or transplant will show up first in yellowing in the lower growth, as the tops borrow mobile nutrients. Or, if you have a ppm/EC meter, you could check your runoff to get an idea of how much is left in the pots. In Happy Frog, I feed or transplant when the runoff falls below 1,000 ppms/2 EC.

 

[Educatedbystoned]

The yellow tips look like a touch of minor nute burn, but I wouldn't worry about it. You might have caught a hot bag of Happy Frog. The plants are looking over-watered (speed bumps and thickness of the leaves), and a little over-lit (edge curl), so I might back off the watering frequency and light intensity a bit. The need for feeding or transplant will show up first in yellowing in the lower growth, as the tops borrow mobile nutrients. Or, if you have a ppm/EC meter, you could check your runoff to get an idea of how much is left in the pots. In Happy Frog, I feed or transplant when the runoff falls below 1,000 ppms/2 EC.

Honestly surprised they are over watered since I’ve only watered them twice to far. I do have a ppm meter but I’m going to wait until my next watering to measure the out water

 

[RootFarmer]

You're in soil. Forget testing run off. All that will tell you is how much of the nutrients you're wasting by washing them out of your soil. Don't water to run off in organic soil like you're using. Bring your soil pH up to around 6.6-7.0 because your plant will struggling to access primary and secondary macronutrients at a pH lower than 6.5.

 

[BackwoodsCultivation]

I've got one plant out of 4 currently that developed similar tip burn on a few leaves. I did absolutely nothing and it evened out. Leaves grew out fines just without the tips. I say let it ride, looks great otherwise!

 

[Phyto]

I’m using a szhlux 400w light at 4 feet distance,
Ph water to 6.0-6.4
No nutrients feed yet
Soil-> recipe 420 topped with happy frog soil

What could the yellow be? Do they need nutrients about now? They sprouted 7/27/24

I wouldn’t sweat that. Starting mild nutes would be fine.

 

[LoveGrowingIt]

@Educatedbystoned - Dry air can cause yellowing of the leaflet tips. What are your temperature and humidity?

 

[fishmon]

I wouldn't sweat the tip burn. I'd venture nutes are a tad high but should be fine. I'm more wondering how to keep photons in check when she starts getting some height. Not seeing a dimmer on that model.

 

[Farmville]

Get the Photone app and use it to make sure your ppfd is in the right range. You have yellowing at the tips of one plant. If it was yellowing on every leaf tip I would suspect nutrient burn or to little watering. Since it’s just this top I would say your light is turned to high and to little water is being fed. When the light goes up everything else must ramp up with the plant as well. Otherwise a bottleneck effect will happen. To little water for a plant with speedy growth will cause leaf damage similar to light burn.

Since plants grow outside under 2000ppfd at times it’s nearly impossible to burn your lights with led lights. That doesn’t mean you can’t be having to much light.

 

[Educatedbystoned]

Get the Photone app and use it to make sure your ppfd is in the right range. You have yellowing at the tips of one plant. If it was yellowing on every leaf tip I would suspect nutrient burn or to little watering. Since it’s just this top I would say your light is turned to high and to little water is being fed. When the light goes up everything else must ramp up with the plant as well. Otherwise a bottleneck effect will happen. To little water for a plant with speedy growth will cause leaf damage similar to light burn.

Since plants grow outside under 2000ppfd at times it’s nearly impossible to burn your lights with led lights. That doesn’t mean you can’t be having to much light.

I’m still trying to figure out what it is. I did raise my light and dimmed it from 300w to 200w. They were about 300-400 par on the app. The yellowing is still happening on the new growths. Couple new nodes came up but it’s still yellowing on the tips. I haven’t fed it or anything. Just ph water with silica and calmag

 

[Farmville]

Recipe 420 is a hot soil that probably caused your yellowing on that one plant since your pods is good. Some people go to 600 in veg. So you are fine there. Is it the organic 420 you are using or the Bhang version?

 

[Educatedbystoned]

Recipe 420 is a hot soil that probably caused your yellowing on that one plant since your pods is good. Some people go to 600 in veg. So you are fine there. Is it the organic 420 you are using or the Bhang version?

It’s the normal red label organic bag

 

[Farmville]

It’s the normal red label organic bag

Okay I would say you need a calcium-magnesium bottle to add to the soil during days you don’t feed a light veg nutrient line probably a few weeks into the regiment I would skip into.

If you are low on calcium magnesium in your soil it will lock out the uptake of your nutrients that are in your good soil

 

[HerbalEdu]

What could the yellow be?

i have had slight yellow tips happen rather often depending phenotypes, never seen it spread afterward ...

 

[Educatedbystoned]

I wouldn't sweat the tip burn. I'd venture nutes are a tad high but should be fine. I'm more wondering how to keep photons in check when she starts getting some height. Not seeing a dimmer on that model.

It’s a different type of dimming, you can active it at 1/3 power with only turning on 4 of the 9 light strips. I bought the ppfd meter app on phone. It reads about 300-400 par at max high with only 4 bars on

 

[fishmon]

Ah ok. Just a heads up, calibration to your specific light is important for the the app to render best results. Refer to manufacturer par map at given distance, set light output at max, test app against map, then calibrate app to map PAR if needed. I'd recommend becoming familiar with DLI (daily light integral). PAR is a photon measurement per second (micromols/s). DLI takes into account the seconds per day and returns total photons per day (in mols/d). The photone app allows selection for hrs per day. I've used this chart for general reference and seems to work fairly well but keeping an eye on node spacing may indicate tweaking. Nodes too tight=dial light intensity down. Nodes too far apart (stretching), increase light. More light drives more photosynthesis which equals more water, more nutrients, etc. I personally dont push plants to the max and get satisfactory results cruising about 35 DLI from mid/late veg on through flower. Note DLI will get adjusted when changing to 12 hr cycle.