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Fertilizers and Their Uses

There are a few different types of fertilizer. The two most popular, and the ones ExperTrees recommends are the granular (slow-release) fertilizer and the water-soluble (quick-release) fertilizer. Before buying fertilizer you must first understand what the numbers on the packaging represent. All fertilizers have these three numbers, and they represent the proportion of Nitrogen, Phosphorus and Potassium as a percentage of the total contents. The first number represents the nitrogen content, second number represents phosphorus, third is for the potassium. They are always listed in this order. Choosing which fertilizer is easier when you know how the plants use these nutrients.

Nitrogen promotes leafy growth and will always be proportionally higher in lawn fertilizer such as a 20-3-4. Nitrogen is represented but the first number and produces rich, dark green colour in a healthy lawn. Nitrogen deficiency: stunted growth, off-yellow/green colour. Cause: lack of organic material, a cold, waterlogged or poorly drained soil, pH level too low, and low bacterial action.

Phosphorus is essential in promoting good root developments and will always be proportionally higher in plant-starter or Transplant fertilizers, such as 5-15-5 or 10-52-10. Fertilizers with a high phosphorus content should be used for ALL new planting though out the first season. ALL plants benefit for phosphorus in becoming well established. Phosphorus deficiency: dull greenish in colour, poor root growth. Cause: lack of organic material to produce humus, pH level too low, acid or clay soil, cold waterlogged and poorly drained soils, low bacterial action.

Potassium provides overall strength and vigor and is important for winter hardiness and root development. Potassium deficiency: leaves turn a blue-green colour, and brown scorch marks appear on the tips of shoots and in the leaf margins. Cause: free-draining sandy soils and chalky soils, lack of organic matter.

Other deficiencies that may occur:

Calcium plays an important part in the growing tips above the ground and in the tips of the roots below the ground, plus helps in the formulation of cells and strengthening the plant structure. Deficiency: poor root growth, the tips of the leaves unsightly. Cause: acidic soil, pH too low, lack of organic matter.
Magnesium helps to form chlorophyll and works with phosphorus which in turn assists in seed formation. Deficiency: yellow/green colour found in the older leaves of the plant, affecting the younger leaves at a later stage (this is called ‘chlorosis’). Cause: sandy soil, lack of organic matter.
Manganese assists in the formation of chlorophyll. Deficiency: yellow/green to yellow leaves. Cause: over-limed or chalky soil, too much organic activity.
Iron plays an important part in the forming of chlorophyll. Deficiency: yellow leaves and other parts of the plant (the green sections) containing chlorophyll. Cause: chalky soil, lime soil, over-liming and any other condition where iron becomes insoluble.

Brand Names

When buying fertilizer, choose the brand name products, not necessarily the cheapest. Here is a list of the brands that ExperTrees suggests:

C.I.L. / Golf Green
Wilsons
Plant Prod
Miracle Grow
Green Earth
Smart Cote
So-Green
Vigoro
Scotts
Canada Way

Fertilizers and their Uses

NOTE:

The various manufacturers use different number formulation for the content of nitrogen, phosphorus and potassium, but essentially do the same job. The different numbers are used more as a marketing tool.

Lawns

Sod and Seed-Starter
10-20-5
7-21-7
18-24-12

Lawns - spring fertilizer with crabgrass control
24-3-6
20-4-8
22-2-2

Lawns - in fall with weed control
12-3-18
6-8-16
12-8-16

‘Green Earth’ Natural Organic Lawn Food
9-3-4

Liquid Lawn Fertilizer with Weed Control
16-5-5
20-3-4

Moss Control Fertilizer for Lawns
1-0-1

Vegetable Fertilizer
12-10-5
5-10-15

Tree and Hedge Feeder
18-4-6

Plant Starter or Transplant Fertilizer
5-15-5
2-14-0 (bone meal)
12-0-0 (blood meal)
7-7-0 (blood and bone meal)
10-52-10

Evergreen Fertilizer
10-3-6
12-6-6

All Purpose Garden Food
5-10-5

All Purpose Fertilizer
7-7-7
8-12-6 (Pink)
20-20-20

Tomato and Vegetable Food
6-12-12
15-15-30

Perennial Food
6-9-7
12-12-12

Annual Flower Food
12-14-12

Hanging Basket Food
14-14-14

Rose Food
6-12-6
8-14-10
15-5-13

Rhododendron / Azalea / Camellia Food
4-12-8
9-12-8
15-7-7

Bulb Food
3-11-0
9-9-6

Clematis and Vine Fertilizer
5-9-8

Ultimate Tree and Shrub Food
16-8-8

Fish Based Fertilizer (organic)
5-10-5

All Purpose Fish Based Fertilizer (organic)
6-6-6

Muskie Fish Fertilizer (organic)
5-1-1

Flowering Plant Fertilizer
15-30-15

Rose, Tree and Shrub Fertilizer
28-14-14

Evergreen and Cedar Feeder
30-10-10

Ever-Acid (for acid loving plants)
30-10-10

Houseplant Fertilizer
15-15-18

Hydroponic Fertilizer
10-6-16

Super Phosphate
0-20-0

Muriate of Potash
0-0-60

Soil Sweeteners

Granular Gypsum - a natural source of calcium and sulphur, absorbs harmful salts from the soil.
Dolomitic Lime - a natural soil conditioner that neutralizes acidic soil and provides calcium and magnesium