Oh, will stop fertilizing them and see what happens. Thanks.
I don't know if you can reverse what has been done. Maybe one of our experts can help out.
Stop fertilizing for the time being (I agree; they may be ‘burned’) but up your watering to morning and evening; especially if it’s a really hot and/or windy day. Make sure your pots have good drainage, and never let roots sit in water; death to most plants in pots via root rot.
If they start looking better, then I would fertilze every time you water with a diluted liquid or granular fertlizer such as Miracle Grow, or my FAVORITE, Algoflash for tomatoes. You can use that on your basil, too.
If using Miracle Grow or another granular, make a lighter solution than normal (about half what’s recommended) if you’ll be watering 2x a day. With the Algoflash you can water and feed every time at regular strenght; 2 capfuls per 2-gallon watering can.
I cannot recommend that stuff enough, and not just because I sell it, LOL! My tomatoes and peppers have NEVER and I mean EVER looked better. :)