HELP! Upper leaves browning

[Backyardwidowfarm]

So we noticed this on three of our outdoor plants. Seems to only be affecting the upper leaves and other than this the plants seem fine. Someone suggested calcium deficiency but from our research that doesn’t really happen with outdoor plants. Because it’s summer and they’re in fabric pots we’re having to water every other day. Been using Fox Farm nutrients and Silica Blast. Any help is greatly appreciated.

[Gjourney101]

How hot has it been. I see a lot of signs of heat stress

[Backyardwidowfarm]

Because of the tent it hits over 100 even if it’s only in the 80s outside the tent. Joys of trying to grow in your backyard. First year it was aphids, second year it was spider mites this year’s going to heat I guess. Thank you for the help.

[Canuck147]

It would be nice if people posting would give us a description of their whole grow.

My ESP is not working so good today - I'm feeling you might have a small fan moving air around? If so or if not - get a big fan and get those plants moving.

[Backyardwidowfarm]

It’s an outdoor grow. In a tent. No fans. Tent is sitting on two cinder block all around so there’s a foot and a half of screen that runs around the whole bottom of the tent. FFox Farm Ocean Forest pHd tap water.

[Canuck147]

Your flirting with possibility of mold of some kind if you don't get your air moving in your grow area. You say it's open on the bottom - so have a fan in the shade blowing into the area.

[CaptainWiese91]

So because they are outside they can’t suffer from a cal mag deficiency? Never heard that before.

what is the Ph levels in all those plants ? Could be a good option to start there.
if the PH levels isn’t quite on spot, they will have easily access to get heat stress or sick of any kind.

[Backyardwidowfarm]

Thanks I’ll look into that.

[crucialbunny]

In my opinion it looks more like an excess of calcium rather than a deficiency. Look it up and you'll see what I mean.

[CaptainWiese91]

To much cal mag in the soil ?
Then you are using a really big amount of cal mag in the water feed.
I fed my plants with cal mag in every single watering I gave them, through out the grow. And never in my life I had a cal mag toxicity

[Rwise]

What I see is a sudden PH change/shock.
Why in a tent outside?

[Backyardwidowfarm]

Sorry forgot about this. Turned out to be heat stress from touching the plastic of the tent. Had them in a tent for a bit of privacy but ended up taking the tent down during the last month. Got spider mites and wasn’t going to have enough room in the tent to properly deal with them, and was running out of room in general, so I took the tent down. Made it much easier to take care of everything. We got lucky it ended being our most successful crop.