Brown spots, guessing ph issue

[Hondo4921]

Hello fellow growers. I have some brown spots popping up on a plant I just moved to my greenhouse 2 days ago. The brown spots were starting in the tent and have continued since being outside. I don't think the change in environment has anything to do with my problem. Growing a berry bomb auto in a 5 gal fabric pot with coast of maine stonington blend. This is my first run with this soil. Still have another plant inside with the same setup just a different strain and noticed I may have one leaf on that plant doing the same thing. Both plants are about 5 weeks old. I suspect it's a ph issue. It's my understanding that I don't need to ph the water with this soil because it is organic but the leaves that show the issue are through the middle and lower areas of the plant. I haven't started giving any nutes yet but plan to in the next week or so. I'll start adjusting ph next watering I guess. Was just hoping for a second opinion or feedback from anybody that has used this soil before. Any help is much appreciated. Happy growing.

[JeffInCanada]

Hi Hondo4921
That plant is looking good. The leaf markings look like a calcium deficiency to me....but that is just a guess. Have a read of the attached page. PHing is important. What kind of soil is it?

[Hondo4921]

I am using Coast of Maine Stonington blend soil. It's organic and they say after a month nutrients should be used. I did read the calcium deficiency tutorial but I thought it looked more like a ph issue to me but I guess trying some cal-mag won't hurt.

[JeffInCanada]

Keep in mind it was only a guess, see if you can figure it out. Another thing you can do is a PH test of the run off water. That Calcium GWE page mentions a low rootzone PH isn't the best for calcium uptake. If you do add Cal/Mag go low & slow. I suggest a good watering with a half strength dose...see what happens.

[Catfish22]

A lot of autos are cal-mag hogs. I would agree with JeffInCanada .

[Hondo4921]

I'll have to give her some on the next feeding. Thanks for the feedback.

[PLreef]

Looks like ph problems but a littlecal/mag can't hurt. How are you testing ph?
I'm using the same soil in my current grow. It's really nice stuff. Organic or not, I still test and adjust my water ph.

[Hondo4921]

Been using a ph pen on my other plant that I have in fox farm ocean forest. The ph of my tap water is usually around 7.0. Guess it can't hurt to test and adjust it. I plan to keep using this soil so I'll just need to start adding nutes after 4 to 5 weeks I guess.