Just going to drop this here as a FYI.
If you have chosen to grow in soil then you should use the attributes your plant receives from that soil, such as the microbes, mycorrhazae, enzymes etc.
Using a basic bag soil even such as FFOF and you put 3 1/2 gallons in a 5 gallon plastic pot and then water with bottled nutrients to run off and then wait until its "Sahara dry" before watering again that is just plain wrong.
First you're doing two things roots hate the most, too wet for a day or two, then too dry for a day or three.
A very dry soil changes the ec, concentrates sodium and nutrients in the soil, kills off root tips and hairs and feeder roots.
You're just begging for problems.
If you want to grow in soil then go with LOS in large 20+ gallon fabric pots, using a Clackamas Coots or similar soil recipe that has lots of aeration.
Plant a cover crop for its many benefits, one of which helps drainage and uses excess water, add worms, also helps keep soil loose and airy.
Then you water EVERYDAY and never ever allow your soil to dry out, not even the top 1/4", you keep a nice thick mulch layer on top and these bright white healthy feeder roots will come to the surface of your soil.
Last few grows I've been watering just a bit everytime I walk into the grow room, just a cupful or so and I have microdoses of various things like coconut water, Fermented Plant Juice, sprouted seed tea of Alfalfa, Ferticell Algae etc. In the water.
The mycorrhazae will flourish and before the plant starts to flower will actually be larger than the plants own root system and feed the plant more than its own roots do.
None of that can happen when you flood poorly aerated soil in a small plastic pot and then wait a week plus for it to dry out bone dry to the point plant wilt, its insanity.
If you wish to use bottled nutrients or you just do not have the space for 20+ gallon pots then you should go with coco and again water EVERYDAY and never ever allow the medium or the roots to dry out.
Or of course could go hydro, needless to say you never let hydro get dry.
Which should prove the point that roots have absolutely zero problems growing in wet conditions because the problem is never the water, the problem is always lack of oxygen.
In a well aerated and constantly "moist" soil especially if you water with highly oxygenated water the roots grow like wildfire.
They stay in that perfect zone of growth 24/7.
Hydro is still much trickier than growing in a proper LOS, the microbes and enzymes in LOS help keep the pathogens away.
I've never seen anything but bright white roots in my pots.
