The Organic Garden Plot
By George
Bushell
(Some tips for gardeners at Orient Park and Anderson Road.)
- Drainage
- pH Balance
- Insects & Diseases
- Weeds
- Watering
- Groundhogs
- Conclusion
Drainage
Drainage is considered by most gardeners and agriculturalists as the
most important factor affecting plant growth. With the exception
of perhaps rice, plants require good to excellent drainage if their
root system is to develop fully and produce the healthy and abundant
growth we all desire. Some plants are "shallow-rooted", (e.g.
peas) and require only a few inches of well-drained soil, while others,
like corn, thrive on three or four feet of well-drained
earth. However, no plant likes to "stand in water".
The most noticeable effect of a "water-logged soil" is slow growth and
a pale yellow-green colour (roots which sit in water cannot properly
utilize many soil nutrients, especially nitrogen). A "wet soil is
a cold soil" is a well known agricultural saying that is especially
relevant early in the growing season when temperatures are low and the
soil needs to be as warm as possible in order to promote seed
germination and vigourous root development.
What can you do, then, to improve the micro-drainage of your garden
plot? One of the easiest and most beneficial practices is to
plant in "raised beds". This will raise the seed bed as well as
provide drainage depressions around the bed. The soil in the bed
will drain better and the small ditches will assist the water in the
lower soil layers to evaporate. There are added benefits as well:
the soil in the raised bed will warm up faster in the Spring; it will
be deeper and less compacted where your plants are growing (better
carrots, etc.) and will probably yield more produce from your plot than
if you planted in the traditional rows.
pH Balance
The pH balance of your soil is often ignored by gardeners, but it
can be a crucial factor in the successful growth of some plants.
A pH scale indicates whether your soil is acidic, alkaline, or
neutral. A reading of 7.0 means a neutral soil, a level of 4
indicates a highly acidic soil while readings of 8 and above reflect
very alkaline soils. Most plants grow best in soils with readings
from about 6.0 to 7.5. (See also the pH table in the
Newsletter.)
Ritchie's Feed and Seed tested samples from Orient Park and found the
soil at this site to be relatively acidic (from 5.0 to 6.0).
Because of the closeness and similarity of the soil at Anderson Road,
it is most likely acidic there as well.
As you have probably noted, the "brassica", or cabbage family, have the
greatest problem thriving under such soil conditions. There is an
added problem with this family as well: formerly, both the Orient Park
and Anderson Road sites were used for market gardening and as such were
planted to considerable quantities of brassica. Some were
infected with a fungal disorder called club root and the soil became
infected as well. The spores of this fungus remain in the ground
for years and can re-infect members of the brassica family when they
are planted. Furthermore, this fungus thrives in acidic
soil! Consequently, our problem.
Don't give up, however. Many gardening books indicate that the
effects of club root can be significantly reduced by the simple
application of lime, pulverized limestone, or some alkaline substance
(e.g. wood ashes). So give it a try. Work at least one to
two lbs into the soil around and beneath each plant. You could
even work more into the soil part way through the season. (Note:
Ritchies sells limestone in bags at a very reasonable price!)
Insects
and Diseases
Gardeners often feel that they must wage war against insects and
disease (in addition to the weeds and groundhogs). But take
heart, it only seems that way sometimes. With a little knowledge
and planning, the problems can be easily overcome. Firstly,
because of the concentrated nature of our garden plots, we cannot spray
or use toxic insecticides or fungicides. It would be highly
inconsiderate to spray your tomato plants in the morning when your
neighbour might pick lettuce to eat that afternoon (sprays drift
imperceptibly over great distances).
Nevertheless, we can do much to counter insects and fungal
disease. B.T. (Bacillus thuringiensis), a bacteria, is very
effective against many soft-bodied larvae, especially cabbage worms,
and is non toxic. However, one of the most effective methods of
insect control is still the "old" way: hand-picking (if you are a
little squeamish about handling the little wigglies, use a pair of
rubber gloves). Colorado potato beetles can be completely
controlled in this way as can most other insects. If you remove
the Colorado potato beetles as well as their bright orange egg clusters
(from the underside of leaves) you will have very few leaf eating
larvae to deal with.
Blights and other diseases can be more difficult to control without the
use of toxic sprays, but there are some things we can do. The
most important is to ensure that your plants are strong and growing
vigorously. A healthy plant can resist most diseases and stress
caused by disease. So read your gardening books about what
nutrients and growing conditions are best for each type of vegetable
you grow. Blights can be a particular problem some years
(particularly in August if the weather is damp and relatively
cool). The spores that cause this fungus disease remain in the
soil and infect lower leaves as rain and overhead watering splash
from the soil onto the bottom leaves. The next rain or watering
causes the spores to be "splashed" onto a higher level of leaves, and
so on, causing, in some years, your tomato plants to gradually lose
their leaves in a bottom to top sequence. Consequently, tomato
blight can be lessened by removing the lower leaves, giving each plant
lots of space, and by not using overhead watering.
Weeds
Uncontrolled growth of weeds can ruin a garden and sometimes
discourage a gardener to the point of surrender. But this needn't
happen to you if you do a little planning and keep ahead of their
growth. The greatest weed problem that you could encounter at
Orient Park and Anderson Road will be caused by "good old twitch
grass". This perennial grass propagates by sending up shoots from
its roots and the more you disturb and break up its roots, the more it
seems to thrive. Short of using herbicides, which are not allowed
there are really only two ways to control this primary noxious weed.
The first involves digging your plot to a depth of eight to 12 inches
in the Spring before planting, and sifting out the crinkly, white-brown
roots from the soil (use a potato fork and remove all roots from the
site). This will take several hours but will be highly
effective. The second way, which allows you to spread your effort
throughout the year, involves the diligent and continuous hoeing of the
grass as it breaks the surface. If the growing part of the grass
is continually removed, the roots will, over a season, weaken and die.
Other weeds also thrive at our sites, as they do in every garden that
ever was or ever will be, but hoeing, cultivating, and hand picking can
easily destroy them. If you pull them with the roots, or at least
cut the plants below the growing crown, they die immediately and do not
regenerate as does twitch grass.
Watering
The "right" amount of water and the correct method of application is
very important to the healthy growth of your plants. In most
years, you will not have to water very often, but there are times when
it is important. At transplanting time it is important that you
soak the ground thoroughly and that you ensure that your plants have
plenty of moisture until their root systems become established.
Later in the season, if you encounter a prolonged dry spell and you
wish to water your garden, it is important that you do so
properly. Do not simply sprinkle the upper surface of the
soil. Thoroughly soak the soil to a depth of six to eight inches,
and only water infrequently when you use this method (e.g. once a
week). Frequent shallow watering causes the roots to remain near
the surface where they are not as effective.
Groundhogs
These animals can be a problem at Anderson Road, but there are some
effective control methods. If groundhogs start causing trouble,
give your Anderson maintenance representative a call and he/she will
see if
one of the overall collective approaches is justified.
Conclusion
Only a few topics can be covered in a small newsletter. For
more information about the subjects discussed here and for details
about soil nutrients, companion planting, organic gardening, etc.,
refer to the many gardening books at your library or book store.
Gardening may seem like one long list of problems after reading this
article, but the problems can easily be overcome. Granted, there
are challenges, but the rewards greatly offset the problems.
Good gardening!