Garden compost and well-rotted animal waste/manure added to the soil will supply some plant nutrients, but in most gardens the amount available is rarely sufficient for optimum plant feeding. That’s why you need to feed your plants.
These specially balanced plant foods supply the nourishment plants need to produce strong root systems, healthy stem and leaf growth and abundant flowers and fruit.
Each group of plants needs different amounts of the major plant food elements Nitrogen, Phosphorus and Potassium. That’s why you will find various formulations to feed different types of plants around the garden and in the home.
Potassium (K): Helps to improve flower quality. Strengthens a plant’s resistance to disease.
Nitrogen (N): For strong, healthy stems, leaves and shoots. Provides good colour to leaves.
Phosphorus (P): For sturdy root growth.
Other nutrients essential for plant growth include magnesium (Mg), which is used in the formulation of chlorophyll in leaves, sulphur (S) and calcium (Ca).
These are needed in very small amounts and are often part of plant foods used to feed lime-hating (ericaceous) plants and those growing in hanging baskets, pots and other containers. They include iron, manganese, copper, zinc, molybdenum and boron.
Even though some soils may already contain these nutrients, they may not be present in a form that is easily available to the plant. For example, iron is most easily absorbed by plants in its chelated or sequestered form. Some residual iron may be present in the soil yet applications of plant food will supply easily absorbed iron that will help to prevent leaf yellowing.
The best plant food to use is the one that most closely matches the needs of the plant. You will find there are granular products that are applied direct to soil that give long-term feeding that lasts for several weeks or months, ones that are diluted in water before application that need to be applied regularly or continuous release feeds that supply nutrients for up to 6 months from one application.
Traditional plant food products are man-made and provide carefully balanced nutrients that are released either quickly or in a slow-release way over several months.
If you want to grow your plants in a more natural way you will find plenty of products that are prepared using recycled vegetable and animal wastes enriched with minerals obtained naturally from rock sediments.