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Phos-Mag 8-19-10+5Mg Fertiliser 20kg

£25.80 inc VAT £21.50 ex VAT
QTYPrice per itemSaving
1 - 4 £25.80 £21.50
5 - 9 £25.20 £21.00 3%
10 - 24 £24.60 £20.50 5%
25 - 49 £24.00 £20.00 7%
50+ £23.40 £19.50 10%
  • Can be used all year round.
  • Ideal for hedges, shrubs, trees and woody perennial plants.
  • Can be used to treat plants with phosphate and/or magnesium deficiencies.

Full Description

Phos Mag fertiliser is a quality mix of NPK specifically designed to promote growth on trees, hedges & woody perennial plants. This mini-granular blend fertiliser offers an excellent spreading pattern which will release over a 6 week period. Phos Mag can be applied at any time of year providing the tree or plant is actively growing. 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.

The application rate will depend on how many times you intend to apply the product. If you require a detailed recommendation then please contact us.

Understanding Fertiliser Analysis: 

  • Under the metric system the unit of measurement is a kg
  • Recommendations are given in kg/ha
  • A fertiliser with the analysis 8:19:10 contains: 8% nitrogen, 19% phosphate, 10% potassium, 5% magnesium.
  • So in a 20kg bag: 8% of the 20kg is Nitrogen i.e. 1.25kg N, 19% of the 20kg is Phosphate i.e. 4.75kg P, 10% of the 20kg is Potassium i.e. 2.5kg K, 5% of the 20kg is Magnesium i.e 1.25kg Mg.
  • For more information on Fertiliser rates visit 

Our Recommendation

  • Always read the product label before use.
  • If you are looking for an all around liquid fertiliser look at Nutri-gem Liquid.
  • For applying fertiliser over large areas look at our Pro Fertiliser Spreader.
  • If you require a tonic to aid stressed plants, look at Hort-booster.
  • Improve the pH of your soil by applying Granulated Lime.
  • Find out what nutrients you may need in your area by using our Soil Analysis kit.

Technical Specification

ProductPhos-Mag 8-19-10+5Mg Fertiliser 20kg
Spreading Rate50g per m²
Period Of UseAll Year Round
Pack Size20kg
Active Ingredient8% nitrogen, 19% phosphate, 10% potassium, 5% magnesium
Application MethodSpreader, Spread By Hand
Area of UsePaddock, Pasture, Trees, Ornamentals, Amenity Turf, Plants, Horticulture
Pack Size Coverage400m²
Safe For Use OnGrass, Paddocks, Pasture, Around Fruit Trees, Conifer Safe, Around Shrubs, Around Trees
Granule Size2-5mm (Maxi)

Product Calculator

How much Phos-Mag 8-19-10+5Mg Fertiliser 20kg will you need?

Purchase the correct amount of product for your requirements with our product calculator - which will tell you how much product you require.


Calculator Disclaimer - This is guide only, For crop specific rates please check the product label.

£25.80 inc VAT £21.50 ex VAT
QTYPrice per itemSaving
1 - 4 £25.80 £21.50
5 - 9 £25.20 £21.00 3%
10 - 24 £24.60 £20.50 5%
25 - 49 £24.00 £20.00 7%
50+ £23.40 £19.50 10%
Click & CollectIn Stock for Click & Collect
DeliveryIn Stock for Next Day Delivery
DeliveryIn Stock Delivery or Collection
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