05/09 - First day in week 9. I am trying not to put stress on the plant not to delay its development, watering every other day and adding silica to improve its health.
07/09 - Continuing with LST and defoliation to give more light to the buds. The plants are drinking like crazy.
09/09 - I have to travel for 5 days. Buy an automatic watering system, I hope this goes well. I added some nutrients to the water and the pH was around 6.2. Set the watering schedule to 1 watering per day, and about 1 liter per plant per day.
Only on one leaf of one plant. Is this some fungus or virus?
It looks a bit like coffee rust, but I couldn't find anything else like it.
How should I proceed?
Thanks in advance!
Pretty certain this is Leaf Spot Fungus otherwise known as Rust Fungus... and you'll need to jump on this quickly as it spreads fast... it spreads by spores that you can't even see so don't think you've got any time to waste here... I won't go into all the details of what you need to do as this article is very thorough.. Do give it a read and get going so you don't lose your entire grow...
https://www.urbanorganicyield.com/rust-spots-on-leaves-during-flowering/
Good luck!