Vanishing Tomato Plant

My once robust deck tomato plant all of a sudden looked like it was being eaten.

Vanishing Tomato Plant

It was a sunny cool early September afternoon. I decided to take a book and join my cat Margaret on my deck chair, one of Margaret's all time favorite things to do. Mine, too, especially when I don't have anything pressing on my schedule. I'm retired now, I thought, I can take a couple of hours to relax and read.

A few minutes later, out of the corner of my eye I saw my once beautiful potted tomato plant vanishing. Most gardeners will confess they may have garden dreams but they often don't realize when they come even close. Our minds are making mental notes spotting something else that needs to be done instead of appreciating what they have accomplished so far. I tried to shut that part of my brain off for a few more minutes but I couldn't concentrate on my book. I had to take a closer look.

Tell-tale skat under my vanishing tomato plant gave me the first clue of what was happening.

The first thing I noticed was that the leaves were now gone from the lush top of the plant. I had just moved the plant to the left a couple of days ago for fear it was too top heavy so I had a very recent impression of how lush it had been.

As I looked closer, I found the culprit. More like culprits, I counted six that I could easily see.

Here's the culprit, a tobacco hornworm, which has a voracious appetite.

The tobacco hornworm is one of two caterpillars that can devour a tomato plant on their way to becoming a moth. The tomato and tobacco hornworms are very similar in markings and size but this one is a tobacco hornworm. I had a number of  3-4 inch Carolina moths on my deck earlier this spring so I am guessing these are their progeny.

With our record summer temperatures this year, it appears the caterpillars waited until the temperatures where cooler before hatching and kicking off their metamorphosis cycle. Much like their more flamboyant, and endangered, pollinators, the Monarch butterflies, Carolina moths are part of the family of pollinators that keep plants propagating themselves. Many of those plants are our sources of food.

I have several tomato plants finally having fruit ripen, we can share. I am keeping an eye on my other tomato plants in case those are getting munched on as well. I would still like to have a few fresh tomatoes this year. 

If I decide I have too many, I will freeze the caterpillars and feed them to my birds and frogs.

Have you seen tobacco hornworms on your tomato plants this year?

Charlotte

Tomatoes Dropping Flowers

A Beefsteak tomato at Bluebird Gardens with blossom drop from record hot temperatures.

Tomatoes Dropping Flowers

When I dream of my summer garden, or see a summer garden quilt throw, I look for tomatoes first. If there is one vegetable that represents summer vegetable gardening, it's these wonderful fruits that add color, flavor and good antioxidants to our salads and other food.

Our local newspaper asked me to call someone about their tomatoes. The gentleman was polite on the phone but clearly frustrated. His 6-foot high tomatoes in barrels at a 7 Ph level where flowering but then the flowers were falling off. He said something similar had happened to his potatoes last year.

Several Possible Factors

There are several factors that cause tomatoes to drop their flowers, starting with the impact of record high temperatures. Tomatoes, like most flowering plants, go into survival mode if temperatures are above 90F for five or more days in a row. We just set record temperatures for June in Missouri so the record hot temperatures may be a leading culprit.

Plant survival mode means most systems are shut down, including pollen production. It’s why a plant may seem to die in hot weather and yet reappear the following year. As long as the roots can pull through, most plants will survive.

High Temperatures and High Humidity

Tied to temperature is high humidity. Humidity that is too high prevents pollen from sticking to the stigma once it is released. Without pollen, there are no pollinators and without pollinators, there are no flowers that produce tomatoes.

Leading tomato pollinators are native bees, especially bumble bees. These little hoodlums of the bee world literally shake the plant, releasing pollen all over the stigma and themselves. When high temperatures shut down pollen production, they also put bees out of business.

Next, two more factors that can impact successful tomato growing. Any guesses what they might be?

Charlotte