A Soil Sample Primer - Megen Hall, High Mowing Sales Associate
first and most important step in nutrient management is getting to know
your soil. Taking a soil sample is a simple and inexpensive procedure
that will help you to determine appropriate amendments specific to your
garden. Many gardeners apply lime or sulfur and an all-purpose type
fertilizer with a predetermined measurement of nutrients as a catch-all
way of amending their soil, but this can cause nutrient imbalances in
the soil. The best way to confirm your soil amendment needs is to
determine your existing nutrients and pH by taking a soil sample and
having it tested by your county extension service.
Soil tests are usually performed in the fall or spring, but
should be done at the same time each year. This will allow you to
observe the general nutrient and pH trends in your garden and can give
you insight as to whether you are under- or over-fertilizing. If you
base your soil amendments on the results of the test, then you can more
accurately maintain a proper nutrient balance.
collecting a soil sample, you want to be sure that the tools and bucket
that you use are clean and free of any soap, chemical residues, or any
other foreign substances which
skew the test results. For greatest accuracy, randomly gather soil
from eight to ten spots in your garden, avoiding areas that are
irregular, such as areas that accumulate standing water, etc. This will
help to ensure that your sample is representative of your whole
garden. It is also helpful to take your cores when the soil is
relatively dry, but if this is not possible then you can allow your
sample to dry at room temperature.
Soil probes and augers are ideal tools for taking a soil
sample, but if you do not have access to such tools, a spade or a trowel
can be used. The important thing is that you sample the same amount of
soil at the same depth (sample from the surface to a depth of 6-8
inches) in each of your sampling locations. Combine all your soil cores
in a bucket and mix well, being sure to break up lumps and remove any
debris or stones.
Most testing services require approximately one pint of soil and will
usually provide a mailer or specific container to send your sample in.
It is equally important to accurately fill out the sample information
sheet which contains all the information needed for your agent to
provide you with your recommended soil amendments. Many agricultural
extension agencies have their sample information sheets available
online, but you can also contact your agent directly to obtain the
proper paperwork and mailer needed to complete your test. The following
link can help you locate the extension service in your region.
You can also contact your local garden supply store, as they will often
offer to send in samples as a service to their customers. Test results
are usually available within 2 weeks.
Good luck getting to know your soil!