gardens by daisy moore

Home  |  Garden designs  |  Naturalized gardening  |  Help with your garden  |  Garden Tips Spring  Summer  Fall  | Contact Daisy





Daisy Moore home

Garden designs

Naturalized gardening

Help with your garden

Garden tips

Spring Tips

Summer Tips

Fall Tips

Contact Daisy



Making Sense of

Fertilizer Labels

It is often difficult to know which fertilizer is the best choice for you. There are numerous formulations, many suppliers and all sorts of slogans and colourful packages used to entice you to buy. Armed with a bit of knowledge, you can see beyond the hype and make intelligent choices.

Fertilizers are concentrated fertilizer particles of the major nutrients required by plants. Nitrogen, Phosphorous and Potassium are the three ingredients listed, in that order, in large numbers on the label. On the side label of the package, it will also state any other ingredients included. Calcium, magnesium, iron, micronutrients and the percentage of organic matter are common components of many specialty fertilizer products.

The first number states the concentration of nitrogen in the package. A fertilizer formulation of 24-4-8, for example, contains 24% nitrogen by weight. This means that for every pound of fertilizer you apply, there is approximately 1/4 pound or 0.24lb of nitrogen. Nitrogen promotes leafy growth and is commonly associated with making the grass green. A fertilizer with a high concentration of nitrogen, compared to the other ingredients, is useful for home lawns, deciduous and evergreen trees and to accelerate the growth of most plants.

The second number states the concentration of phosphorous in the package. 24-4-8 contains 4% phosphorous by weight. Phosphorous promotes rooting and is commonly associated with "starter" fertilizers. 18-24-12 or 10-52-10 are two examples of high phosphorous fertilizers which are recommended at the time of seeding. Phosphorous is also useful in vegetable production since it promotes flower set and heavy cropping. In flower production, phosphorous is required to produce robust blooms.

The third number on the label states the concentration of Potassium. 24-4-8 contains 8% potassium by weight. Potassium is required by plants to assist in the uptake of other nutrients. It is associated with increased hardiness and vigour for all plants. Although the immediate effects of potassium is unseen, it makes a tremendous difference in the overall health of the flower and vegetable garden.

The balance of the three major nutrients is an important consideration when choosing the proper fertilizer. 24-4-8 is suitable to maintain an established lawn but will encourage too much leaf growth at the expense of flowers or vegetables in the other portions of the garden. As a general rule, lawn fertilizers should be used exclusively for turf.

If you are looking for a good all-purpose fertilizer for the flower garden, select a product which is high in phosphorous and contains a medium amount of nitrogen and potassium. 8-12-6 would be a good example of this. For the vegetable garden, choose a product which contains higher amounts of both phosphorous and potassium. 5-10-10 would be an example of this.

Beyond the basics, there are sometimes fertilizer products specially made for certain crops since it is known that specific nutrients will assist in making them grow to their potential. Tomato fertilizer, for example, should contain additional calcium since it is well known that calcium will reduce the incidence of blossom-end-rot. Azalea fertilizer should contain nutrients which will make the soil more acidic and supply the nutrients which are needed for acid-loving plants such as sulphur and iron.

Another consideration when choosing fertilizers is the source of the ingredients. Natural organic fertilizers are made from natural ingredients such as manure, bonemeal or compost and are traditionally low in concentration of the major nutrients. They do, however, contain many other nutrients and organic matter which are useful for plant growth and the health of the soil. Synthetic fertilizers are man-made particles of the specific nutrients and are, therefore, more concentrated. These should be used in conjunction with compost or organic mulch. The third type of fertilizers is the water solubles. These are very concentrated particles which are made into a fine powder and need to be dissolved in water prior to application.

Whichever type or brand you choose, make sure you read the label on the front, sides and back of the package. Check the guaranteed analysis to see what ingredients you are buying. The last step would be to ask an experienced person at the garden centre if you have made the proper choice for your own garden.

Daisy Moore, 1999.



Other summer garden tips:

(click on the tip you want to read)


Extreme Conditions
Growing Roses
Summer Lawn Care
Propogation by Cuttings
Sources of Native Plants
Making Sense of Fertilizer Labels
Annual/Perennial Combinations
Climbing Plants
The Dry Garden
Ornamental Grasses
Chooosing A Good Gardening Book
Companion Planting
Preparing the Compost for Fall Use
Getting the Most out of your Vegetable Garden
Repairing Lawns From Summer Stress
All About Grubs
All About Onions
Useful Herbs for the Home Garden
Screens and Hedges




Home  |  Garden designs  |  Naturalized gardening  |  Help with your garden  |  Garden Tips Spring  Summer  Fall  | Contact Daisy


Daisy Moore 2005