FOXFARM BUSH DOCTOR MANGANESE, 1 QTIn Store Location: @A8 You probably think you've covered all your bases: your NPK is on point, your pH is dialed in, and there isn't a pest in sight. Sounds good, but did you know that plants without Manganese can suffer? This important micronutrient plays a valuable role in photosynthesis, nitrogen assimilation, and helping plants hold their own against environmental stresses. OMRI listed for organic use Registered CDFA Organic Input Material