As a first time outdoor grower, let me tell you what I have found/discovered in only a few days. I grew my plants from seed and everything went just fine. Decided way back that I wasn't going to bother with PH since I figured I would be okay with just assuming everything was good. I decided a few days ago to get the PH droplet kit that comes with the little testing vial. Best thing I've done yet. I am watering with creek water right beside my plants. It's fast moving, well aerated, and I assumed healthy. Put my plants in the ground and watered with the creek water with 1/4 strength ferts, THEN went and bought the PH kit and a few other things. Took a sample of the creek water home and it had a PH that was 8+! Went back out today and the plants looked okay but the new growths on the tops were "off looking" and seemed kinda wrinkly and the tips were burned. The leaves were all curved upwards also. Took a few gallons of the creek water and PH'd it to 6.5 or close to and flushed the plants out. I'll check on them in a few days but I bet they look better. I am using the Fox farm trio along with Pro-mix BX, Marine Cuisine (I know it's time release), coir, and perlite. Don't really know where I"m going with this, other that just to say that I am thankful I decided against my initial thoughts and bought the cheap little PH droplet kit. Having said that, I am only PH'ing with feeding water (plain water and water with ferts added) and I am not PH'ing runoff since I'm growing in beds in the ground. I don't know the soil PH other than most of the soil is stuff I added witch should be fine. IMO, in the very least, PH your feeding water.