Purple underside of leaves

Hey!
This is my first post here.

I've chosen to register here because of all the good hits from searching on the web.

My case:
Planted some nicely germinated bag-seeds about 11 days ago. I've kept them under 18-6 to 24-0 CFL light.
Temperatures have been around 20+C(68+F) to 27+C (80+F). I live about 600 meters above sea level, and the outdoor temp is around 5-C (23 F). This generally makes the air very dry.

When I place them in total darkness, I place them in the kitchen cupboard. Over the sink there are some lights, which makes it somewhat tempered inside.


Over the last 2-3 days one of my plants have gotten this very purple color on the underside of the leaves. (See pic)

Has this something to do with the strain, which for me is a uknown one, or is it me treating it bad?

I also think the stem is quite thin. The flower seems heavy for the stem. Is this something to worry about?

If something is not so clear, just ask. And sorry for any typos, or any bad use of English.


Regards
Just another first time grower

No one?

1stTimeEvr said:

No one?

Click to expand...

Not enough info to tell if it is a problem or genetics

the 68 degrees could cause it in some strains

"purple color on the underside of the leaves
Has this something to do with the strain" no leafs are green

" I place them in the kitchen cupboard." you need air movement
" purple color " on stem i use Epsom salt in water to clear up
"I also think the stem is quite thin. The flower seems heavy for the stem. Is this something to worry about" maybe
need pic of plant

I had purp under the leaves
What genetics you running..
all the plants in this cross,had this going on..

68 degrees is cold enough to turn any strain purple, its called cold stress.

its ok bro its normal i just had 15 little ones do this no worries

Thanks for replying.

Terry, I'll check up on the air in the cupboard. It's plenty enough air there for 4-6 hours, but I'll put a fan in there to circulate the air.

It's the first time ever doing this, and I'm fascinated by the speed of the growth. The attached pictures may differ a bit, they're about 36 hours old.

I found this if it helps.

Purpling: accumulation of anthocyanin pigments; causes an overall dark green color with a purple, red, or blue tint, and is the common sign of phosphate deficiency. Some plant species and varieties respond to phosphate deficiency by yellowing instead of purpling. Purpling is natural to some healthy ornamentals.

Your plant looks good. I doubt it's a P deficiency this early on. P deficiencies, for me anyway, usually start at the leaf edges and work inward. I'm thinking cold stress here as well. When I forget and leave the window open my plants will go a bit purple on me too.

Don't worry about it, you are looking good. The stem is a little stretched but nothing bad and you can always pot up that stem. Make sure your substrate has good drainage and good luck.

Hey start preparing a plan for when the plant gets bigger. You won't be able to put it in a cabinet for much longer. But welcome to the grow world, it's addicting and a lot of fun. You picked a helpful community to ask. Goodluck

Wat is the temp of ur water when u water? Cold water can induce purple'n too.

" they're about 36 hours old." that's fast
mine took 7 days to get this size lemon haze this one real slow even to pop a root took a week also

you are going to need a bigger cupboard lol
also small fan on low will make stem stronger

Guys! Thank you for answers.

Sorry for bailing on this thread, but I've been a bit busy. I've switched from putting them in the cupboard to letting them stand in their box when darkened. (Much better airflow).
Even though the temperatures reach as low as 62 degrees indoors when I'm out, I can manage too keep it around 72 degrees with the lights on. The reason for the cold is the freezing outside (8-9 degrees).

Also - I water my plants with cold water from the sink. Plug the sink, fill some water, put the plants in there, and let them absorb water until soil on top is moist.

I see that my worries about the leaves apparently was for no reason.

So here's an update and another request for guidance:
Plan:
Re-pot and change the soil of the two ones who have grown to be largest.
Two others still growing in size (planted 1,5 weeks after the two first ones).
___________________

Took plant 1 out of the pot, and checked the roots - they filled the 8cm small pot I used.
I know I ripped some roots, but it was still plenty left. I guess it's going to be ok?

Plant 1 (the biggest one): All pictures taken before changing soil/pot

First picture:
Can anyone determine gender on this one, or is it too soon? I also see the stem is "changing it's skin". It looks like the baby-skin got too small and peeled off.



Second picture:
Does anyone know what's starting to happen to this leaf right here?



Third picture:
Just for a size comparison (2,5 inch HDD)



Plant 2

First and second picture:
Can gender be determined on this one?



Third picture:
Size comparison just like plant 1:

Is anyone feeling like replying to my last post?