There are always three numbers on you fertilizer bag
e.g.. 3.1.5
The first number represents Nitrogen. Nitrogen provides your chlorophyll to your plant.
This allows your plant to grow quicker, taller and to develop a darker color.
If you use a fertilizer high in nitrogen it will stimulate a quicker growth for your roses,lawns,citrus trees and shrubs.
e.g.. LAN is high in Nitrogen.
The second number represents phosphorous.Phosphorous stimulates the root development of your plant and will increase flower ability and the size of your blooms.
Always use a fertilizer high in phosphorous when you establishing a new garden.When you sow a new lawn and planting new trees it is recommended that you use a fertilizer high in Phosphorous.
The third number represents Potassium. Potassium has many function. It guards your plants against many diseases, it helps to protect against drought and could tolerance.Potassium helps with root development as well as Photosynthesis.
It is always good to use fertilizer high in Potassium at the start of winter and summer, this will protect your plants against extreme temperatures. High Potassium is also recommended when plants have been damaged by insects and diseases.
Always take care as to when you apply your fertilizer, best time of the day will be very early in the morning or late afternoon.The best time to apply is when it rains.
Water in well to prevent your plants from getting burned by the fertilizer.Your other option is to use organic fertilizers to minimize the burning process.