Today we’ll go into a few problems that you may or may not
be seeing in your vegetable garden. I’m dividing the topics into two
categories: Biotic and Abiotic. Biotic problems mean those issues that arise
due to a biological, or living agent, whether it be insect, disease, or human!
Abiotic are those that are outside of the above category, so can be
physiological, environmental, or cultural in origin. Sometimes the line can be
a little less than distinct between the two as we’ll see in several examples.
Let’s get sleuthing.
Biotic:
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David B. Langston,
University of Georgia, Bugwood.org |
Be aware that some varieties of squash or zucchini have
patterns on them that may look similar to powdery mildew. If you aren’t sure,
you can send a picture to your local Extension office or you can look for
patterns vs. a more random distribution. Patterns are likely natural, more
random is more likely to be powdery mildew.
If your garden succumbs to powdery mildew every year in your
cucurbits, your melons, squash, cucumbers etc. there are a few different
management options. You can trellis your vine crops and grow them vertically;
this improves air flow and reduces ambient humidity. You can also remove the
oldest leaves as the plant grows, leaving 5-7 of the youngest leaves at any time.
Finally, if summer squash is the disease-ridden culprit in your landscape, you
can succession plant, plant new squash about a month after your first crop,
rogue the first set out once powdery mildew begins to establish.
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Paul Bachi, University of Kentucky Research and Education Center, Bugwood.org |
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William M. Brown Jr.,
Bugwood.org |
Tomato spotted wilt virus – Another of the diseases that can impact tomatoes, tomato spotted wilt virus is another common disease seen in home gardens. This disease can be transmitted by an insect called a thrip, when it feeds on the tomato it can infest the plant with the TSW virus. Leaves may develop a cupped appearance, with the bottoms becoming bronze and then dying (leaving brown or black tissue). Most typically it can be seen on fruit with concentric rings developing across the fruit. Fruit is fine to eat but may have a poor flavor. It is best to purchase resistant varieties if you’ve had issues in the past. Pull and dispose of the infected plant.
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Brenda Kennedy, University
of Kentucky, Bugwood.org |
Gerald Holmes, Strawberry
Center, Cal Poly San Luis Obispo, Bugwood.org
Blossom End Rot – Blossom End Rot occurs in quite a
few plant species including tomatoes, peppers, cucumbers, zucchini, squash etc.
We often begin to see it as plants first
ripen in the early summer and into mid-summer. While it is technically caused
by poor calcium in the fruit, this does not necessarily mean that there is
insufficient calcium in the soil. Crushing up eggshells or adding calcium to
water is not likely to rectify the issue. Rather, it is good to practice good
“cultural care” by this I mean you want to make sure you are watering,
mulching, and fertilizing the plants as they need to be cared for. Erratic
watering and cold soils lead to most blossom end rot issues, so look to your
hose and your temperatures before amending with nutrients that are likely not lacking.
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A good way to ensure distorted
growth does not occur is to encourage pollinators throughout your garden. Avoid
spraying insecticides unless necessary and grow flowers throughout your space
to feed your pollinator friends.
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Possible herbicide damage
on homeowner tomato |
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Dr. Joey Williamson,
Clemson University. |
As always, check with your local Extension Office to get
more information on this, or any other garden issue. Happy Gardening!
