MrStinkyanswered grow question 3 years ago I was sick of not finding accurate watering information, so I'm putting together a side project for myself to figure out average waterings in soil, all the below from my current grow:
Get a small hand sprayer
Watering in week 1 tip: Get a big plastic cup and cover the plants over like a helmet so you dont spray the leaves - I burned my first plant doing that. Do this every day until the plant no longer fits under the cup.
Each watering should be dry in 24hrs and keep your humidity like 70-90%
Week 1 - 100ml per day, increased 20ml per day, sprayed across the surface of the soil and 5-10ml at the bottom of the stem in a gentle trickle every day.
The trickle at the base to give the plants tiny root some water straight away. The spray all across the top to soak into the top few cm of the soil to let the spreader roots rush across the top of the pot to chase the water, you have airpots so it makes sense to encourage lateral growth ASAP
Week 2 - 250ml per day increasing 10ml per day (plant should be too big to fit under cup this week so just soray carefully) and a couple of squirts at the bottom of the stem
Week 3 - 350ml per day
Week 3 mid week - 1 x 1L watering of the whole pot (I am organics) - let half of it dry (weight pot before and after) and then a 250ml watering on top
Week 4 - up to 500ml per day and rising - about 100ml directly at base if stem every watering now
Week4 mid week - 1x 1L water / 2 days dry (almost saturated)
Week 5 - 750ml per day and rising steadily
Continue until they reach max water intake per 24hrs
With the 1L feeds, do it slowly, in 2 x 500ml sessions about 1 hour apart to allow the top of the medium to absorb water, and then the 2nd watering for the water to flow to the lower substrate.
The reason for the 1L feeds is Im on dry organics and 1L almost gives me run off, I cam just feel moisture under the pots (fabric, 11L) so I'm not watering to runoff, but helping the roots lower down in the pot chase a nice big drink. It am hoping it also allows me to build into a constant wet / dry cycle, eventually I hope the pot should synchronize and need a full watering every day(ish).
I try to imagine watering the plant like spring rain showers man, and a bigger plant will definitely suck up more rainwater than a smaller plant.
It helps to know the weight if your pots wet and dry for sure, put them on scales if you need to - I did / do, thats how I know how kuch my girls are drinking on a daily basis 🤣
I also 'roughly' follow VPD charts to allow for maximum transpiration, my temps are also sweet at 20oC-26/27oC
The liquid amounts were kinda based on fractions of the pot too, my 1L feeds are like 10% of the pot, increase or decrease your waterings in proportion based on the size of the pot in the early days, I dont water to runoff cause I'm not synthetic.
Disclaimer: the above post is PURE 100% 2nd-grow bro-science, but it's definitely F working man and I've had no signs of over watering yet