What makes an organic garden different from an ordinary one? There are two major differences - the use of pest control and fertilizers. How fertile the soil is depends on the amount of nitrogen, potassium and phosphorus present in it. Nitrogen enhances the growth of flourishing shrubbery while phosphorus strengthens stems and roots.

The plant is protected from disease and cold by potassium, and is a requirement for each plant that is more than a year old. For traditional vegetable gardens, synthetic fertilizers involving a mixture of these three main nutrients are used to enrich the soil and enhance the growth of healthy plants. The same ingredients, however, are used in a different way for organic vegetable gardens.

Compost is a natural way to enrich soil. It can be produced easily in the backyard of your kitchen using refuse from the garden and the kitchen. Lawn cuttings, leaves, weeds, carrot tops, fruits and vegetables which are spoiled, pine needles and corn stalk are all prime candidates to form good compost. The decomposition of all the organic material in this compost heap helps to enrich the soil by producing certain bacteria and fungi which convert nitrogen to ammonia and nitrates, by a process known as nitrification. Natural deposits of phosphorous known as rock phosphates can be used as a part of the compost.

Substances such as wood ash, seaweed, rock ground potash, potash salts and tobacco stems naturally contain potassium. So you see, nature provides all three essential nutrients and this can be tapped in the form of organic gardening. A balanced amount of nutrients will go to the plants and make them healthy.

However, this organic material takes a longer time to decompose and thus it should be left for a while longer than synthetically produced fertilizer - about a fortnight beforehand is an ideal time. To raise the pH balance of the soil and make it less acidic, ground limestone can be used. Many soils don't have magnesium, which dolomite limestone can provide. If you find that your soil is too alkaline, then use finely ground sulphur to make it more neutral and less alkaline.

The theory of pest control in organic vegetable gardening is that pests should not be completely eradicated but kept at a level where they can be managed easily. Gardeners also plant pest-resistant varieties of plants, and natural predators are used to keep the insect level manageable.