Leaves Yellowing

[Luketheduke]

Problem: Leaves on 3 of my G18s are slowly turning yellow.

Medium/grow method: Happy Frog mixed w extra perlite. Some in 3.5 gal plastic and one in Fabric smart pot.

Feed: and supplements used: At this point they can go about 48 hours before they need more water. For supplements they are on Fox Farm trio. Big Bloom, Grow Big then Tiger Bloom. They just got their first feed of Grow big-2 Tsp and CalMag-1 Tsp mixed into a gallon of water and PH down to 6

water source: Well Water being PH adjusted to 6

Strain/age: G18. Starting week 4.

light used: Mars Hydro TS1000w at 100% at around 17 " above tallest canopy. (Was 22 but theyve closed the distance)


Climate: Grow tent in garage. Temp daily between 71°-83° F. RH is between 40-60%

Additional info: pics attached. Yellowing only on higher leaves. Just watered yesterday.

 

[Luketheduke]

Anyone please help! Its getting worse. I dont want my girls suffering

 

[CDN88]

I'm not one to look to for advise, too new to this, only on my second grow and first autoflower grow. But my first photo period looked like yours and I added more Cal/Mag and it greened right up. However, I'm having even worse issues that you on my auto Bruce Banner at the moment, so don't just listen to me lol. But I don't think a little extra Cal Mag would hurt.

 

[Arthur]

Why are you running a pH of 6 in soil? That's pretty low, more like hydro #s... It should be somewhere 6.3 to 6.7. (Lower early on, higher in flower)
If it was in my tent, I'd do a slurry test and pin down the pH of the soil. Haven't run for a couple years, had issues with the pH sliding in mid-flower. Would drop into the mid 5s. With your low pH feeds, that would be my knee jerk reaction.

 

[Luketheduke]

Why are you running a pH of 6 in soil? That's pretty low, more like hydro #s... It should be somewhere 6.3 to 6.7. (Lower early on, higher in flower)
If it was in my tent, I'd do a slurry test and pin down the pH of the soil. Haven't run for a couple years, had issues with the pH sliding in mid-flower. Would drop into the mid 5s. With your low pH feeds, that would be my knee jerk reaction.

My ph hasnt ever been below 6.2 and never above 6 5 w the water i put in. Slurry test put my ph at 6.27

 

[Arthur]

Sorry, your first post says pH'd to 6 in 2 spots. Assumed you were pH'g to 6.

Going into flower I'd be trying to move that soil pH up some. Girls going to want more Phosphorus than available in the low 6s.

 

[Luketheduke]

Sorry, your first post says pH'd to 6 in 2 spots. Assumed you were pH'g to 6.

Going into flower I'd be trying to move that soil pH up some. Girls going to want more Phosphorus than available in the low 6s.View attachment 1279931

When I water tomorrow should I ph to 6.6 or so since my soils currently in the 6.2 area?

 

[Arthur]

I probably would. I kinda think the interveinal lightness might be low mg, looking at the charts, that has you down in low uptake area, a small bump might care of it.
I try and stay around 6.2 to 6.4 thru vegetation provided my slurry tests follow along. About the time the stretch starts and I'm moving towards flowering, I'm feeding between 6.5 & 6.7, again looking for the slurry to follow along. Kinda a pain checking, but overall, if things are running fine 3 times is plenty, prior to planting, transitioning to flower, and mid flower.

 

[Luketheduke]

I probably would. I kinda think the interveinal lightness might be low mg, looking at the charts, that has you down in low uptake area, a small bump might care of it.
I try and stay around 6.2 to 6.4 thru vegetation provided my slurry tests follow along. About the time the stretch starts and I'm moving towards flowering, I'm feeding between 6.5 & 6.7, again looking for the slurry to follow along. Kinda a pain checking, but overall, if things are running fine 3 times is plenty, prior to planting, transitioning to flower, and mid flower.

I bumped it to 6.6 this time w no nutes today when i watered. Im hoping that will help get the soil back in the 6.3-6.4 range since it was around 6.2 w/ my last slurry.

The yellowing/oranging/browning has either stopped entirely or slowed so much I cant tell its advancing anymore. One of the other G18s is now starting to have the same issue. At least I know it wont progress as far now. The last G18 I have is still perfectly fine. No issues. But im going to keep them all on water for another few weeks I think.

 

[Luketheduke]

I went to check on the plant this morning. Its drooped and wilted. Leaves and stems that hold them falling over. A bunch of affected leaves are now super dry and crunchy. Some never bothered changing color before they got this dry.

At the base of each leaf (where they meet the stem) is flimsy and has browned. Some of the stems are like limp noodles.

What the fudge just happened. Yesterday she was perfectly fine and seemed to be recovering. The soil was dry so I watered with 1 liter phd at 6.6 like we discussed w/ no nutes at all. And today its like this....

@Arthur
@Mañ'O'Green