I think it is actually under watering as in "not enough water when you water" by your description but also they need food. You shouldn't swing your pH around between using just water and when feeding though so hopefully you have a pH meter, if not that's a shame because we don't have time right now. You need quality soil nutrients at this point and I will recommend Botanicare Pure Blend Pro Grow for Soil along with Botanicare Cal Mag Plus. Hopefully you have a local hydro shop you can go buy that now if you don't have a soil nutrient already. You shouldn't swing pH around so if you can set your pH as close to the pH of your water but remain between 6.0 and 7.0 pH. So for example if pH of your water is 7.3 then set your nutrient solution to 7.0. Then you need to water slowly until water is dripping from the bottom. You do this by wetting the entire soil on the top of the planter until there is 1/4th inch of water or so there then wait until it soaks in, wait a little longer at first, then do it again. It will take a lot of times to get water to drip if you are doing this correctly and if your soil is being watered correctly. Then you wait until the pot is extremely light and do it again. When your planter is completely light / almost bone dry you still have a day before it will even droop. That's when I water when I can feel almost no water left but it isn't completely dry obviously.
More on pH
We need the pH more acidic actually 6.5 pH is what most nutrients I've used is buffered at. But abrupt pH changes cause noticeable stress "wrinklied and twisted leaves, odd growth problems". We therefore try to move pH slowly a tenth at a time. 7.0 with nutrients, 6.9 just water and pH down, 6.8 with nutrients again.
Organic vs Chemical
You have a choice to go organic still even if you use chemicals now you can flush them out really well later. I don't know how to get your plants corrected using organic stuff though. If they weren't in such bad shape I could do it but I'm just not organic savvy enough to trust it. That miracle gro always needed to be flushed for organics so it isn't as if by using these nutrients we are ruining your organics because you have none.
P.S. Check for spider mites I've had bad luck with miracle gro, not using it to grow with for that it is great. House plants and stuff not pot