Container gardens may be the answer for persons with limited
garden space. Residents of apartments, condominiums, retirement
homes, or houses on small lots can still enjoy gardening using
containers. Containers are mobile, allowing a gardener to take
the plants along or move them for an instant splash of color.
Senior gardeners can plant and tend to raised containers, when
standard gardening may be too strenuous or low. What better way
is there for children to have their very own first garden? You
can enjoy your plants more fully by locating them on patios,
balconies, or window boxes.
Container gardening, however, is not without its problems,
especially in North Carolina. A plant growing in an exposed
location will be under more stress, dry out faster, and will need
a regular watering schedule. Consistent rains tend to leach the
nutrients from the containers, requiring a regular fertilizing
schedule. Large containers can be expensive and difficult to
move
when filled with potting mix. The advantages far outweigh the
problems, so let's get started growing container style.
Soil Mixes
Soil is not always best for container gardening. When ordinary
soil is saturated with water, the air spaces are filled, removing
essential air from the roots. This is why a soil substitute,
often called potting mix, is recommended. The mix may contain
some soil (called soil mix) or no soil at all (a soilless mix).
Additional ingredients such as peat moss, vermiculite, and
perlite allow rapid drainage but still hold sufficient water for
plant growth.
Purchase potting mix from nurseries or garden stores under a
variety of trade names: Jiffy Mix, Pro Mix, Metro Mix, Pro Soil
and others. If you have only a few containers you may want to
take them to our local greenhouse and have them filled with their
greenhouse potting mix (for a fee).
Making your own potting soil can be fun if room is available
and the soil recipe is simple. A different mix is not needed for
each type of plant. One common mix includes 2 parts sandy loam
soil, 1 part sphagnum peat moss, and 1 part perlite or builders'
sand. There are many varieties of this basic recipe. A mix
containing soil has not been pasteurized, which kills weeds and
disease organisms, so use these mixes for established plants.
Potting mixes should be free of disease organisms, insects, and
weeds.
Consult references in your local library or Extension office for
additional information on Container Gardening, including recipes
for mixing large quantities of potting mix from a variety of
ingredients.
Containers
Containers come in a variety of styles and sizes. Of course, old
buckets, cans, and similar containers can all be recycled. The
essential thing is that the container have holes in the bottom
for draining excess water.
Plastic: Plastic containers are available in a variety of sizes,
shapes, and styles and a variety of fashion colors. Plastic
containers are light in weight, which is both an advantage and a
disadvantage. Being light-weight, they cut down in weight to be
carried. On the other hand, when a plant dries out the plastic
container may not be heavy enough to keep the plant upright.
Clay: This old favorite is perferred by many gardeners for the
earth tone color it provides. Clay is porous and moisture is
lost
readily from the sides and bottom. Clay pots are breakable
and heavier.
Wood: Wood is a popular material for containers. Redwood or
cedar is relatively rot resistant and can be used without
staining or painting. Exterior grade plywood and other types of
wood can also be used. Avoid using wood treated with creosote,
penta, or other phenolic compounds, since vapors can injure some
plants. Always use copper-treated lumber if perservative-treated
lumber is needed. Wooden containers are excellent for
portability and can be purchased or built in a wide variety of
sizes, shapes, and styles. Several container garden references
offer plans for building attractive containers.
"How big should the container be?" This question can best be
answered by considering the type of plants you plan to grow.
There is a balance between the top growth and root systems of
plants. Small plants can be grown in fairly small, shallow
containers while larger plants need a larger container. Plants
in "stressful" locations such as a hot patio with a south
exposure, or
in elevated locations, may need a slightly larger container than
ones less exposed.
Most annual flowers and small vegetables will grow in containers
from 5-inch pots to gallon or larger sized containers. Larger
vegetables, such as dwarf tomatoes, peppers, or cucumbers will
require 1 to 3 gallown containers. Full-size tomatoes and roses
will require at least a 3-gallon container.
Fertilizer
Since potting mixes drain water rapidly, causing fertilizer to be
washed out of the containers as you water, you will need to
replace lost fertilizer. Lighter mixes will require more
frequent fertilizing than heavier mixes containing soil.
Remember, you are growing a plant with a small, constricted root
system so regular fertilizing and watering is important.
Many gardeners prefer to apply a diluted water-soluble fertilizer
solution at every other watering. There are several
water-soluble fertilizer materials available at your garden
supply
dealer, including Rapid Grow, Hyponex, Miracle Gro, and other
products. If you fertilize at every other watering, use only
one-fourth the recommended rate unless the instructions state
directions for continuous feeding for container gardening.
Controlled release or time release fertilizers are also becoming
widely available. These are pellets designed to release
fertilizer gradually over a period of time. Use these
according to directions on the package label.
Watering
Since containers are ususally situated in an exposed location,
water is quickly lost from the containers. Also, smaller
containers have less of a reservoir for holding water until
needed. There is no rule of thumb on how often to water since it
will vary with the type of plant, potting mix, weather
conditions, and type of pot used.
You may find that daily watering is needed during hot periods.
One advantage of using a potting mix is that it is nearly
impossible to overwater since the water quickly drains out of the
container. Check your plants regularly and look for signs of
wilting to indicate a need for water. Another method is to stick
your finger into the upper inch or so of the potting mix to feel
the dryness. Always apply sufficient water to allow a small
amount to come out of the bottom drain hole. This indicates the
container is thoroughly saturated with water.
Potting mixes can be easily washed out of the container, so never
water with a direct stream of water from a hose. Always use a
"breaker" nozzle to break up the stream of water or a sprinkling
can to apply water. A sprinkling can is handy for applying
fertilizer as you water.
Since containers must be watered regularly, you will need to
arrange for plant care when you vacation. Grouping plants
together will reduce their water use. Some ingenious gardeners
have developed a "trickle" device by punching a small hole in a
large container that serves as a water reservoir. The water can
then be channeled to one or more containers. The most reliable
method of plant watering while you are away however, is to
arrange for someone to care for your plants. Watering plants as
well as checking for problems that may develop.
Culture and Care
Plants need care and attention throughout the season. Insects
and disease can be a problem because plants are growing under
more stress and with limited root systems. Control measure will
be similar to those used in conventional gardening. Refer to
North
Carollina Cooperative Extension publications for ways of dealing
with garden pest problems.
What to Grow
Flowers: Many annual flowers can be grown in containers,
especially those that tolerate heat stress. Especially popular
are the many types of marigolds, geraniums, and periwinkle
(vinca). Impatiens will produce flowers in shady locations as
will ageratum, begonias, and nicotiana.
Vegetables: In recent years, there has been an emphasis
on developing varieties suitable for container gardens.
Vegetables require sunny locations and will vary in their
productivity depending on the type of crop. Check seed catalogs
for new varieties developed for this purpose. There are also
several types of "ornamental" vegetables adapted for growing in
containers. Flowering cabbage and flowering kale are attractive
relatives of the standard varieties. Lettuce is available in a
variety of colors and leaf textures. Red chard is another
popular container plant because of its bright red stalks.
Herbs: Many gardeners like to have herbs growing near the
kitchen where they are handy to use in cooking. Basil, chives,
marjoram, and thyme are all easy to grow in containers. Many
gardeners keep mint in containers since it is an agressive plant
that spreads over the garden. Some herbs are perennial and can
be moved indoors for winter use or held in the container until
next year. Many gardeners dig a hole in the garden to store pots
of perennial herbs until the next season.
Gardening Notes
Index
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