Outdoor Nutrient Burn

I know the common way to fix nutrient burn is to flush the pot with water but my girls are growing directly from the ground. Do I do the same deal and if so how much water?

I'm no expert, but if my girls were burnin' from nutrients
i would flush with at least a gallon of PH'ed water ( To soak away some of the nutes and to keep the soil balanced)
Its a lil' bit different outside, yet i would flush just to be on the safe side