well is this 2 foot plant flowering or vegging? what is it in? 1 gallon 5 gallon bucket?
I think you should mix 2/3-1 gallon of solution and get it moist. If she is thirsty and the soil is nice & dry the next day (you check this by sticking your fingers in the topsoil) then you can continue this routine on a daily process. Most likely @ 2 ft, it will prob want a nice big feed one day, and then the next you can either let it be and continue to absorb/soil dry, or if you feel a good bit of the moisture has been absorbed but you still want to allow some time for oxygen to pass throughout the soil & let the roots breathe, then you can have a quart or so of liquid nearby and just use that as a light feed.
It's all about getting in sync with your plants and learning the rates of which they absorb what you give them. Every strain is different, too. So just remember that MODERATION is key in everything! Whether water, nutes, pruning, ...
Hope this helps!
200ml per day until the last 7-10 days of flowering, then up it to 400ml for the remainder
It really can vary on enviornmental conditions tho. If you were indoors and in constant 75 degrees start to finish, you could get technical and say it's this many MLs at this point in time and why. But it can have a lot to do with your enviornmental conditions as well. If you're indoors and have lots of fans on your babies, running dehumidifiers 24/7, and maybe have some heat fluctuations, there's a good chance your plants will increase in respiration as a way to cool and stay comfortable in their climate. With this increased release of water vapor, your plants will now require a more frequent or larger dose to account for this.
So with that said, you should really learn what to look for in soil and plants as signs of how their feeding. Watch them for a bit after feeding them check back in a few hours and make notes in a grow journal about the differences you see in the soil and how they are starting to absorb. Write down how much you used and how strong, so if you find the soil is too wet or they are burned, you'll know maybe you need to reduce feed amount or maybe lower the PPM strength of your solution. Always stay on top of your PH levels, as well! And that goes at least double for hydro, as it tends to fluctuate much more than soil grows.
good to note, the temps are about 85-90 with light on and 75-80 with light off in 12/12. humidity is low during the on period around 40-50% usually and 60-70% at night. theres 4 fans circulating air 24/7 all creating cross drafts and not blowing directly on the plants. ppm right now is about 1800 but i will slowly dilute it to 1500 by adding water as it gets used. ph levels are right around 6.4 and i test any time i make a change to the reservoir.
p.s. thanks for all the help guys.