The Online Gardener's Handbook
Chapter 3: A Word about Soil
Table of Contents
- OMAFRA Accredited Soil Testing Programme
- Learn More
Home gardeners in Ontario spend a lot of money on fertilizers each
year. This is done in the hopes of achieving high yielding fruit
and vegetable crops, colourful flower gardens, and vigorous trees
and shrubs. These gardeners will only be successful, however, if
their fertilizer use is reflective of the natural fertility level
of the garden soils and the amount of compost and manure also being
incorporated into the soil.
Soil testing is a way to help gardeners understand the nature and
fertility of their soil. It also helps protect the environment by
providing gardeners with fertilizer recommendations reflective of
their particular garden. Plants respond in a very positive way to
nitrogen, phosphorus and potassium when applied to low fertility
soils. For many established gardens, where there have been regular
applications of fertilizer, manure and compost over the years, anything
but a minimal application can prove to be excessive. Plants become
too tall and leafy, flower poorly, set fruit poorly and are easily
bent down in wind or heavy rains. Soil testing is the most accurate
tool available to determine the amounts of fertilizer required for
optimum plant nutrition while minimizing the possible leaching of
OMAFRA Accredited Soil Testing Programme
The OMAFRA accredited soil testing programme for home
gardens and lawns provides recommendations for nitrogen, phosphate
and potash along with a recommendation for the amount of lime to
apply if required. The recommendations are designed to provide good
plant growth while preventing or correcting nutrient deficiencies.
Sampling every two or three years is recommended.
Several laboratories are accredited to provide a
soil testing service to home gardeners. See Accredited
Soil Testing Laboratories in Ontario.
Soil Sampling Procedure
- Use a soil sampling tube, shovel or spade.
- Remove four or five cores or slices, 15 cm deep, from different
locations in the garden. (Parts of a lawn or garden that differ
in soil texture or in fertilization practices should be sampled
- Mix cores together, and break up any lumps.
- Draw the sample for analysis from the combined cores.