Fertilizers are applied to enhance the soil’s natural fertility. The rate of fertilizer to apply varies according to the type of tree, soil type,  amount of rainfall and snow melt. Our Alberta soils vary wildly within this region from beautiful black #1 topsoil to sand.  If you have sandy soil, the fertility will be very low; you will need to fertilize every spring.  If you have great topsoil, then your flowering tree may only need fertilizer occasionally.

The following are general fertilizer recommendations for established tree and small fruits in the Edmonton region home garden. Compost or manure can be used as a top dressing as an alternative to commercial fertilizers.

 When to Fertilize: When fertilizing flowering trees and other fruiting plants in Alberta, the timing of the application and amounts are important. Early spring is the best time to fertilize trees and other fruiting plants in Edmonton.  Encouraging late summer growth and ‘growing bigger and faster’ over the summer may result in winter injury – and is not necessarily the best plan!

Important Tip! Avoid fertilizing in summer and fall as this may stimulate late summer or fall growth that is more susceptible to winter injury. Too much fertilizer can cause excessive vegetative growth and can decrease fruiting.  Never apply more than the recommended label rates.

 Flowering and Fruit Trees

If you have recently planted your tree, using a root building water soluble fertilizer like 10-52-10 in early spring is ideal (at label rates).If your tree is three or more years old, it would be considered to be ‘established’.  Check tree growth to determine if your trees need fertilization. Non-bearing flowering or fruit trees should grow approximately 12- 15 inches a year. Bearing fruit trees should grow 8 to 15 inches a year . Trees growing slower than this may need fertilization. If your trees are showing obvious signs of distress like yellow leaves, it is beneficial have a soil test done, and inspect the tree for injury or disease.

What to Use: Apply a balanced fertilizer, such as a 10-10-10, in early spring in April, just before bud break.  Evenly broadcast  fertilizer in a circular pattern beginning about 2  feet from the trunk and extending out slightly beyond the drip line of the tree. If the lawn in the vicinity of the fruit trees is fertilized on a regular basis, there is no need to fertilize the trees. The fruit tree roots will absorb nutrients from the lawn fertilizer. Additional fertilizer may be excessive.