Leaves turn yellow

[invi]

Hi!

Im doing my first attended indoor grow, but have some problems with the leaves.


What Strain is it?
Caramelo (70% sativa - 30% indica),
Sensi star (10 - 90),
Black russian (20 - 80)
All from Delicious seeds

6 Plants
1 month old - from seeds
Indoor
Soil - compo sana universal potting soil

Pot size: ~2x2x2 inch

Size (Wattage) of Light? How Many? 1x 400w MH
Is it Air Cooled? No
Temperature of Room/Cabinet? 75-85 F
RH of Room/Cabinet? 38-65
PH of Medium or Reservoir? - Not sure please see below
Any Pests? Not yet
How Often are you Watering? every 2 days (outside temp is above 80 usually)
Type and Strength of Fertilizers used? none
Size or Square Footage of Room? 7x8
Water supply is from RO filter (EC 50, PH from 5.5 - 6.5)

Im not sure about PH:
When i measured the runoff, it showed 6.8 (water was 6.5ish, bit lower maybe)
When i mix the soil with water and leave it for 30 mins, the PH will be around 5.5 (using 6.5 PH water)

Is it just heat stress? Or my soil is bad and i have repot in different soil mix?


Pics:

Thanks for any help!

 

[YardDog35]

Re: Leafs turn yellow



Your little ones look good! Looks like they are getting a little hungry, slight nitrogen deficiency showing in the yellowing of the bottom leaves.

It would be a good idea to transplant to larger containers. I'm not sure what soils you have available in your area. You will also need a good nutrient for them shortly after the transplant, depending on what soil you will be using.

 

[Captain Kronic]

Re: Leafs turn yellow

Here is a link to help you figure out how to post those pics in your actual thread invi:
Photo Gallery Guide: How to Resize, Upload & Post Photos

Welcome to 420 Mag!

 

[invi]

Re: Leafs turn yellow

Thanks! (Also for fixing the image links - i couldn't figure out how to edit, did not want to re-post)



Do you think when i transplant i can use the same soil?
Found the label, it says:
PH 5 - 6.5
N 200-450mg
P 200-500mg
K 300-550mg
3% perlite


Also i will recieve some more seeds soon - is it safe to start them in this soil?

 

[invi]

I transplanted them, the yellowing stopped luckily, also got some canna terra & rhizo nutes for next week, i hope they will like it
Thanks for the tip, this plant really grows much faster then the ones im used to.

Unfortunately the weather got really hot now, its 90+ F - im so afraid of sex change... If it's getting any hotter ill open the fridge and put them next to it.

I set the dark period to 20:00 01:00, and in the morning i move them to my room
with all windows open and a fan constantly blowing the air. I put them in the sunlight though - should i put them in the shadow to avoid heat? That would mean quite a few hours less direct light.

What you guys do when it gets so hot? I was thinking of air conditioning, but there is only a few weeks like this during the summer. If it just adds a week or two to the veg phase i can live with that, but if it kills the plants, i would rather get a mobile air conditioner.

 

[invi]

Hey again!

I thought i post some pics, how the girls are doing, and also there are bad signs showing on a leaf - would be happy to hear what you think it is.
For me it seems to be calcuim related, but google can be misleading.
Please help if you can, maybe i can stop it before getting worse..

The damaged leaves:

Some more about them - its just vegging, but still i need to show them to someone sometimes

 

[noobie97]

looking good! yes, that looks like a cal mag deficiency. you said you're using RO water, are you supplementing with cal mag?

 

[invi]

Thanks for the help - it seems the issue was caused by trips.
I could get rid of them for a while, but now they seem to have returned

Can anyone tell me if i can still use neem on them in the 4th week of flowering, or that will spoil the taste completely?
If i treat only the leaves, will that mean that all the pests will move on to the flowers?

Another question regarding the dutch haze - is it normal for this strain to have about 50% brown flowers after the 3rd week? It looks a bit like harvest time but it's supposed to be ready after 9-11 weeks..

Here is the trips (at least i think it is)

My caramelo:

sensi star:

dutch haze:

black russian: