Nutrigrow Phos-Mag Flower & Vegetable Fertiliser (8-19-10+5Mg) 20kg. Phos Mag fertiliser is a quality mix of NPK specifically designed to promote growth on trees, hedges & woody perennial plants. While this fertiliser is most often used on trees and shrubs, it can also be used on areas suffering from a deficiency in phosphorus or magnesium.
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