Yellowing Jack Herer! Sick! 4 Weeks Veg, Help! (Pic)

[MacAztek]

Here is a pic of a Jack Herer growing in Hydro. It has been vegging for 4 weeks, with very low nutrients until today. It has gotten yellow over the past few days. Here are the stats of the room:

Lights: 400w MH Hortilux (18" from tips of Jack Herer), 250w HPS.
PPM: Upped it to 500 today, using Canna Vega Nutrients.
Water: RO Water
pH: running around 5.8-6
Temps: around 75
Airflow: Good

What could be the problem? Is the light too close? Have the nutrients been too low, and maybe it will fix itself after adding them today?

I would rather have less nutrients than more, as I burned my plants last crop and killed them.

Please help, thank you!

 

[ICETOKER]

it needs more Nitrogen. up the dose of ferts in your reservoir. I would go at least to ec 1.6

 

[Levitikuz]

it also looks underwated imo...is that in dripper? is it on 24/7? if not whats ur schedule at? def. up ur nutes tho

ur at 500ppms with a plant that size? i would def. go to atleast 1000...my 2 week old from seed Sadhus were takin 1100 (on accident) and they loved it lol....put ur ppms up to atleast 1000...

 

[MynameStitch]

underwater can look just like over watering at first but when the plant droops more down lower you know it's under watering.

Also what setup are you running?

LEv; you may have a plant that liked higher nutirents; but he may have one that is low tolerance; like the thread starter said; better safe than sorry.

Every strain is different.

But I will agree 500 is low for that size of a plant; I would go to about 800-1000 ppm's

Those stems are very purple; definantly got a deficiency going on; up the ppm's a bit

Phosphorus makes the vigor of the plant weak which would give it the droopy look.

What is your temps and humidity in that room?

Also do you have more than 1 strain hooked up to this setup? Looks like you do...
What are your temps and humidity? how close is that light? Cause your leaves are cupping upwards; that can be caused by either to much nutrients; which in this case is NOT; or heat radiant heat

 

[HeadyPete]

Do the plants perk up and get stiffer after a watering? If not, then they are not being underwatered...tread lightly.

This plant seems to be larger than the others and could very well be just needing more nutes. One dose at higher ppm won't kill them. It should green up. Watch the leaf tips for slight tip burn. This will tell you feeding is optimal.

 

[MacAztek]

Well, I don't think it is overwatering. The plants' roots are in the bottom buckets (this is a WaterFarm setup), and are constantly being soaked. Can they still get underwatered even though they aren't dripping?

We bumped the PPMs to over 700 (to be safe), and set the pH at 5.7.

There is very low humidity, and the temp is <75 in the room.

We have Jack Herer (the plant you see), and Spice, and Garlic. The Spice and Garlic were put into the room about 10 days after the JH, so they are a bit off. They aren't is big, so we have the PPMs in those buckets at around 380.

Is that too low?

 

[MynameStitch]

I would first fix the deficiency issue and then see if the plant still needs fixed because from what I see the plant needs food and it's vigor is weak right now; the leaves cuppingwards like that can be from low humidity too if I remember correctly;
Might have it backwards but I will have to double check..... what is the RH in your room?>

 

[MacAztek]

RH? I am not sure what you mean, Stitch.

The humidity is fairly low, I do know.

PPMs are at about 700-750 currently, with pH at 5.7-5.8

We'll see how things go. I am using Canna Vega A+B Formulas for nutrients, any word on this stuff?

 

[MynameStitch]

Rh means humidity....... Cannabis grows good at 45% to 50%


I have seen canna vega nutrients but I think if I remember right some people had issues with micronutrients but that is strain related; if it is not showing micro nutes then don't do anything untill something is needed.

AS for the ppm part you got that fixed now; if it seems to get better slowly up it a little more because it will take nutrients out of the water and your ppms will go down.
So monitor it everyday or few times a day.