1. Nitrogen - promotes leaf groth
2. Potassium - encourages fruit development and fertile seed.
3. Phosphorus - stregthens roots and stems and gives flowers their brilliant strong colours.
Liquid organic fertilisers and powdery blood and bone tend to be faster acting.
When to use fertiliser
Good practise is to always fertilise your garden beds and borders in spring before you plant. This will give your flowers and vegetables a solid start and improve drainage.
Native plants only need a handful of blood and bone now and then. Natives do not like phosphorus so make sure you do not apply fertilisers high in phosphorus.
Types of organic fertilisers
Mushroom compost - high in nutrients and good water holding capacity. Excellent if you want to give your trees, shrubs and annuals a boost.
Cow or horse manure - make sure it is well rotted before you apply. Excellent soil builder, improves texture of sandy soils.
Poultry manure - A good source of slow release nitrogen that promotes leaf growth. Apply to groundcovers to speed up growth.
Blood and Bone - Powder form - very high in nitrogen, with small amounts of potassium and phosphorus. Apply to annuals and newly planted shrubs and trees.
Fish Emulsion - Liquid form - high levels of nitrogen and phosphoric acid. Stimulates lawn and rose growth: also good for ferns and other foliage plants.
Seaweed - Liquid form - Derived from natural seaweed. Great for roses or shrubs that are lacking iron.