To Look For When Choosing Potting Soil
most of us, a soil is a soil is a soil when it comes to
where the rose bush is planted. But to the educated
gardener, selecting the proper potting mix, or medium,
is vital to a plant's health and survival.
That's why there are so
many different kinds of "dirt" or potting
media to choose from, and as you can imagine, different
prices. In fact, the best potting medium isn't dirt at
Choosing a potting medium
can be terribly confusing, but the right mix is the
starting point for achieving ongoing plant health.
Whether it's the initial potting of a plant in a
container, or the repotting of an indoor plant, we must
first understand the difference between the myriad
products on the market.
Basically, there are four
types of potting mixes: 1) all-purpose, 2) premium, 3)
professional, and 4) plant-specific. The base raw
materials used in each dictate why some cost more than
others. The raw materials can include composted bark,
whether from pine, fir, spruce and redwood;
nitrogen-rich compost; peat humus; sphagnum peat moss;
and a lightening agent such as perlite (those little
white things) or vermiculite.
It is important to look
for soil that is even and consistent in texture. Stay
away from anything that looks "clumpy" or has
large, visible pieces of bark.
All-purpose potting mixes
are fine for gardeners who like to add ingredients to
customize their mix with plant food.
The main benefit of the
premium mixes is that they aid in water drainage and
aeration. These mixes include roughly 40% of the same
base raw materials as the all-purpose types, but they
also often include perlite and vermiculite to increase
aeration and improve drainage.
Premium mixes also
feature a wetting agent that helps provide more uniform
water distribution in the soil. This means that the
entire root mass will have water available after each
Some premium mixes
include fertilizer in either water-soluble or
slow-release granular form. A slow-release fertilizer
may be sufficient to feed a plant for 6 to 9 months.
The professional mixes,
feature base raw materials that are more completely
processed than in the premium blends. Additives to many
professional mixes include sphagnum peat moss,
vermiculite, perlite, composted bark finds, and a
nursery operators, and gardening enthusiasts choose
professional mixes because of the consistency of the
product and their ability to better control how the
plant is fertilized.
The fourth type of
potting mix is the plant-specific variety. They
generally tend to be premium mixes. Since different
plants have different needs, each is manufactured
specifically for that plant.
For instance, African
violets, cactus, and succulents have unique root systems
and watering needs. Therefore, special soils will allow
for the proper aeration and soil chemistry for these
The most amateur
gardeners are best served by going with the premium
mixes. The extra cost is worth it, as you get a perfect
mix with all the measured base materials and components
added by experts.
So next time you want to
get down and dirty in selecting potting mixes, remember
that they may look alike on the surface, but behave
differently when they are the surface.
article was written by The Scotts Company with content
assistance from Dr. Rosemarie Rossetti and Dr. Charles
Powell, Certified Landscape Professionals.