Which of these problems is it?

its not a or b

 

If you are watering at pH 5.9 and your runoff is pH 8, then you really need to bring the pH down. I would start there. Get your pH between 6.5 and 7.

 

I would just flush it for a few days with 6.5 ph water. Also if you have catch pans beneath your pots use a turkey baster to suck out your runoff so the palnt do not get wet feet.

 

I'm agreeing with these guys, ph could be the problem here. Flushing with low ph water will help bring down the medium ph (keep checking runoff). It will naturally start getting lower as salts build up in the soil anyways, but you can also use a low ph water to feed, 5.2 is fine if it comes out 6.5-7.0. You will need to keep a constant eye on this for your entire grow.

Best fix ix to start with good ph'd soil to start. Fox Farms adjusts theirs to 6.3-6.8 out the bag, it's one reason why so many have great success with it. You can adjust any soil though with additives, my fav is compost and/or coco coir. 1 part generic soil + 1 part compost + 1 part perlite makes an awesome soil that will give little ph problems and drain really well (a great help for flushing).

Good luck!

 

...wait for your soil to dry all the way out, then flush it w/ h20 in the 6.3-6.5 pH range. Use 3 gallons of water per gallon of soil....and flush it SLOWLY (water follows the path of less resistance)...make sure it goes through the soil and not down the sides of the pot.

.....use rapid dolomite lime for pH issues in soil. Add 1 Tbls. per gallon of soil as a top dressing, and water it in as you normally water. Lime constantly fights to bring your pH neutral (7)

...you should always wait for your soil to dry all the way out before you flush...if your flushing often.

...the pH of your runoff doesn't give a correct pH reading of your soil...it only reads the free H+ ions in your runoff! Your soil's pH, and your runoff's pH will always be different...your soil's pH changes as it drys. (I've had FFOF freash out of the bag w/ runoffs in the 5's!, but the plants didn't skip a beat, flawless)

...I personally suggest to anyone growing in soil to stick with organic fertilizers (while in soil) Soil is too great of a buffer for salts, and the salts build up quickly, which require you to flush very, very often to maintain an acceptable pH....which in trun causes overwatering!

...It's very hard to overfertilize with organics. Any newbie should start there for good results your 1st time (IMO)

 

In my experience, it is quite the opposite. The more room the roots have to spread and uptake nutrients and water, the quicker the plant will grow. More growth below ground, more growth above ground.