Job:06-700309 Title: CPS - Container Gardening Complete700309 - ContainerGardens_001-272_FINAL.indd 202 6/5/17 3:11 PM
Job:06-700309 Title: CPS - Container Gardening Complete
Job:06-700309 Title: CPS - Container Gardening Complete
700309 - ContainerGardens_001-272_FINAL.indd 203 5/24/17 12:20 PM202 chapter 4PATHOGEN PROBLEMS
In addition to insect pests causing potential
trouble in your container garden, there are a
handful of plant pathogens that may appear from
time to time. Though some are more common
than others, most will not become regular issues
in a container garden. Pathogens that live in the
soil (soilborne) aren’t typically problematic in
containers, especially when the containers are
filled with a fresh compost/potting soil blend
every year. But pathogens that spread via wind,
water, and insects can certainly prove problematic
to container gardeners.
It’s important to recognize that when it comes
to these disease organisms, a little prevention
goes a long, long way. Your first line of defense
against these issues is this simple three-step plan:- Plant only resistant varieties. This all-
important step essentially designs the pathogen
out of the system. By choosing vegetable, herb,
fruit, and flower varieties with natural resistance
to a particular pathogen, you’re reducing your
chances of ever facing the disease to begin with.
For example, if you’ve battled a fungal issue
called powdery mildew on your bee balm plants
in the past, plant only selections of bee balm with
noted powdery mildew resistance in the future.
For nearly all of the pathogens listed below,
there are varieties of plants bred to be resistant
to that particular disease organism. When you
purchase seeds or plants from a local nursery or
catalog, any disease resistance should be noted
on the packet or tag. Do your homework and pay
attention to this information. It can save you a lot
of trouble down the line.
2. Maximize air circulation. Many disease
organisms are fungal, and fungal spores thrive
in wet and humid conditions. By spacing plants
properly, and thereby increasing air movement
around them, fungal issues can be slowed or
stifled. Give your plants plenty of room; don’t
overstuff your containers.
By selecting varieties with a natural resistance to
pathogens such as powdery mildew, you’ll save
yourself a lot of trouble.Text Black Job:06-700309 Title: CPS - Container Gardening Complete #175 Dtp: 229 Page: 202700309 - ContainerGardens_001-272_FINAL.indd 202 5/24/17 1:07 PM
Troubleshooting 203- Employ good cultural practices. From pruning
and fertilizing to watering and harvesting, the
care and maintenance tasks you perform in
the garden play a huge role in promoting—or
discouraging—diseases of all sorts.- Water plants during the morning, whenever
possible, to allow enough time for the foliage
to completely dry before nightfall. - Clean your pruning shears after working on
a diseased plant. A simple application of a
spray disinfectant or a quick dip in a 10%
bleach solution is enough to kill most plant
pathogens on pruning equipment. - Don’t overfertilize plants. Succulent, tender
foliage is more susceptible to certain
fungal attacks. - Avoid working with wet foliage. Fungal spores
spread easily from plant to plant on water
droplets clinging to your skin or clothes. - Regularly inspect container plants for signs of
disease. Remove infected foliage and discard it
in the trash or bury it to prevent further spread.
- Water plants during the morning, whenever
Common Plant Pathogens
Viral, bacterial, and fungal diseases are
sometimes a problem in the garden, but they
need to be properly identified in order to be
treated effectively. Here are some of the
common pathogens you might encounter
in your container garden.Septoria Leaf Spot
(Septoria lycopersici)Description: This fungal disease appears as tiny,
round splotches on the leaves. The spots have
dark brown edges and lighter centers. There are
usually many spots on each leaf, and it typically
occurs on the lower leaves first, just after the first
green fruits appear. Leaves eventually turn yellow
and then brown and fall off.Plants affected: Tomatoes and ground cherries
(another species of septoria leaf spot attacks
‘Goldsturm’ rudbeckia).Solutions: Be sure to remove diseased plants
at the end of the season to prevent the spores
from overwintering on-site. Remove and destroy
infected leaves as soon as you spot them and
clean empty containers with a 10% bleach
solution at the end of the season. Organic
fungicides based on copper or Bacillus subtilis
are effective, especially when used as a
preventative measure.The distinctive tiny round splotches on this leaf
indicate an infection of septoria leaf spot. Often
appearing on the lowest leaves first, this fungal
disease is most common on tomatoes.Job:06-700309 Title: CPS - Container Gardening Complete#175 Dtp: 229 Page: 202 (^) Text Black Job:06-700309 Title: CPS - Container Gardening Complete #175 Dtp: 229 Page: 203
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