Hey buddy, what kind of soil are you using? May I suggest a few advice?
First of all, your plant looks very healthy. But, in order to keep them healthy and grow well, you must do several things.
FIRST. Please invest in a good PPM/PH reader. It will save your $$ in the long run.
If soil, please try to keep the ph between 6.3-6.5, that's ideal. Second, your temperature is very low. Seedlings do not like that low temperature. May be you can grow it indoors for the first few weeks and when it gets strong, you can bring it out. Even then, low night temperature like that can stunt your plant very fast.
Autoflowers are like ticking time bomb, you have to make sure you keep that baby healthy all the way because you only have one chance. It doesn't matter what you do, that flowering time is coming! As a grower, you have to focus on good vegetation! One main thing is, you never want autoflower roots to start circling around in a small pot. SO, the idea is to keep it in a big pot to begin with so the roots continue to expand and biggers roots = bigger goods.
Remember this: during vegetation, you want NPK to be - High nitrogen, Low Phosphorous, High potassium. During flowering you want your NPK to be - Low nitrogen, High Phosphorous, High Potassium.
If you remember this, you will have good growth. I also suggest you to look into some beneficial microbes and how these microbes have symbiotic relationship in the cannabis roots.
First time growing anything.. It must be very exciting. But don't let the over excitement fool you and end up overnursing it! I am sorry if I've overwhelmed ya. It is exciting to see a new grower. Cheers and let me know if you have any questions.
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