Working it's way up from the bottom. doesn't seem to be starting at the tips, either. what could be wrong with it?
Phosphorus deficiency can cause necrosis in seemingly random spots and can also cause damage to one side of leaf blades.
compared to the other plants that have a little burn to them, this one looks totally different. if you look at the picture, the yellow is way more intense and isn't in the same spots, or as many leaves, as the others. why would this one be having a deficiency? how can I fix it?
Burn always starts at the tips of the lowest & oldest leaves. I'm concerned that the plants you believe are burned may have a totally different problem. Lockout can affect P usage but pH problems show up primarily on new growth. If it's Phosphorus deficient, it hasn't gotten enough useable P. High-P ferts like Bone meal or most Guanos are the best sources of P.
well, I'm using FFOF right now. may switch over to happy frog, but that's for later. I've read the soil pH for FFOF is 6.8 if I'm not mistaken. the only pH tester I own is the water tester with blue dye. only tells you the pH. umm, I've tested the runoff once. was the same as the when I poured it in (figured that was good). got it to around 6.0 - 6.5. now here is where the problem may lie. I do not have access to filtered water. I've been using tap. I live in a crowded city, so bet your ass it has all the hard metals and chlorine in it. I only have a 5 gallon bucket and 9 plants IN 5 gallon pots. when they were babies, I would let the water sit, and feed them nutes once every other watering, using a quarter of the recommended dosage (FF grow big). since they've been in the 5 gal's, I've not been able to let the water sit for obvious reasons. the pH of the sat out tap water was still 8.0, so I would add some pH down to it. their last watering, I had to cut corners, sadly. fed them fresh tap water, no nutes or anything, put a cap full of some pH down to get the pH down to ~6, and that was that (could the ppm play a part?) there isn't anything wrong with the new growth. that all looks beautiful. its only the older leaves doing this. side note: just wrecked them ALL with too much neem oil. could that play a factor?
I've heard similar readings on that soil's pH. Since every pH meter I ever owned went bad, from straight out of the box to after a couple years of use, these days I really only use wide spectrum pH drops. In order to know a meter is good or bad, you have to test it with something that doesn't go bad nearly as easily. So even if you use a meter, you'll still want to have another means of testing anyway. Wide spectrum drops can be found for as little as $5 a bottle. Since you're using the Fox Farms line, the Tiger Bloom is a good source of Phosphorus. While I always have bottled water on hand, activated carbon filters (Brita, etc.) both purify the water and slightly lower its pH (~6.6). If you keep up on filter changing, this water is great for growing. That doesn't look like it was caused by hard water, though.
yea, that's what I have. the wide spectrum drops. that can't test what's IN the water / soil tho, right? so if it's a P deficiency wouldn't I need a meter? and I'm about to look it up, but how much are those filters? I'll def try out that tiger bloom. you think it is a P def.?
