I would say flush with water for acouple of days to a week & watch the plant get back to normal. Then go back to using your nutes. Water down your nutes some more. Go to maybe half the potency you were using before. Gradually increase your feedings. If your growing in dirt avoid feeding to often, wet dirt can keep your plants roots from breathing well. & if your in a hydro system makes sure the ph level is at a perfect balance. 6-7 ph.