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Tomato Plant Problem #842768

Asked July 26, 2023, 5:12 PM EDT

We have been growing 6 tomato plants in containers the last few years. We switched to containers from raised beds because the raised beds stayed too moist for tomatoes and they suffered root rot. The containers have a 16 inch diameter at the top and are 14 inches deep. They have drain holes in the bottom and I added some more towards the bottom of the sides. We fill them with fresh vegetable soil before planting and feed them every two weeks with Tomato Tone fertilizer once the fruit sets. The plants we planted this year were two 4th of July, one sweet one hundred, one Abe Lincoln, one Juliet, and one Early Girl bush. Over the past two years we have lost over half of the plants. When I discussed the issue with the garden store they suspected that it was over watering, but also said it could be a fungus disease. This year I began spraying with a fungicide as soon as we planted them and kept up the best I could depending on weather. I purchased a 15 inch moisture meter this year so I could tell how moist the soil was towards the bottom of the container. I check the top two inches of soil with my finger and use the meter to see how wet the soil is towards the bottom. If the top feels dry and the meter does not read wet I put about 1/2 gallon on the container. It usually would drain out the bottom. They typically needed water about every other day using this method. We started harvesting fruit last week but noticed three of the plants were starting to turn yellow. Presently it looks like we will lose the sweet one hundred, the Early Girl bush, and possibly one of the Fourth of July's. The other plants appear healthy as of now. I talked to someone at the garden store and showed them photos and sample leaves. They seemed to think the most likely culprit is over watering again. They did note some possible fungus and insect infestation but didn't think it was bad enough to cause a problem. I removed all of the yellow and dried up foliage and will spray with fungicide as soon as the temperature moderates. I have included a few photos of the affected plants. Any suggestions to help save the plants this year or advice for future years would be appreciated. Thanks, Phil Meyer

Hamilton County Ohio

Expert Response

Thank you for your question, Mr. Meyer. How discouraging, after all your efforts! I am impressed that you are persisting, despite these disappointing outcomes.

You said you used "fresh vegetable soil" in the pots. Was this potting soil or soil for vegetable beds? One of the issues with pots that you have addressed by adding additional drain holes is poor drainage. Potting soil is important, as it is loose and aids in drainage. Regular soil intended for garden beds can compact and impede drainage. Because the garden center staff diagnosed over watering, I am wondering if this could be what is going on.

I suggest that you select one of the plants that you do not expect to survive and dump it out. Inspect the soil near the bottom to see if it is soggy. Also, inspect the roots to see if they are waterlogged. If the soil and roots do not indicate a poor drainage problem, then we need to consider other possibilities. Did the garden center staff mention the possibility of blight? This is probably the most common ailment of tomato plants in our humid climate, and it can be spread easily.

Once you have inspected the soil and roots of one of the plants, please write back, and, if necessary, we can continue the detective work.

Best wishes, Char Rae

Char Rae Replied July 28, 2023, 8:01 AM EDT

Char,

 

Thanks for getting back to me so quickly.

 

I still have some of the soil mixture we used for the tomatoes. It is Baccto vegetable mix. I think it is made to be used in both raised beds and containers because on the back of the bag they describe how if you are using it in containers to make sure the container has one or more holes for drainage. The bag doesn’t list all the ingredients, but says it is mostly various types of spaghnum peat with organic fertilizers. Here is a link to their website with a more complete description https://baccto.com/home-gardening/veggie-mix/ . They do tout the water holding capabilities of the mixture.

 

I will inspect the pot and roots of one of the plants that won’t survive after we have harvested the fruit from it.

 

The garden center mentioned the possibility of a fungus disease and recommended a fungicide. Is blight a form of fungus? If so, will a fungicide control it?

 

I’ll let you know what I find out when inspecting the pot of the dead plant. We got over an inch and a half of rain last night, so I’m not sure my inspection will give an accurate assessment.

 

Thanks again for your help.

 

Phil Meyer

From: ask=<personal data hidden> [mailto:ask=<personal data hidden>] On Behalf Of Ask Extension
Sent: Friday, July 28, 2023 8:02 AM
To: Philip Meyer
Subject: Re: Tomato Plant Problem (#0112694)

 

The Question Asker Replied July 28, 2023, 1:53 PM EDT

Blight is a fungal disease, and is probably the most common of diseases that affects tomatoes. Hopefully the websites below will offer useful information, including potential treatment. While it isn't helpful at this point, a preventative that all advice seems to have in common is to look for hybrids that are as resistant to disease as possible, when selecting plants to grow. If you use cages or other devices to support the tomato plants, be sure they and your pots (if you plan to reuse them for tomatoes) are cleaned thoroughly with a bleach solution (1 part bleach to four parts water) and a brush, and then dried in the sun before storing.

Let us know, if you don't find the answers you need in these sites.

Keep gardening!

https://www.thespruce.com/identify-treat-prevent-tomato-diseases-7153094

https://www.thespruce.com/early-blight-on-tomato-plants-1402973

https://www.thespruce.com/tomato-leaf-diseases-1403409

Char Rae Replied July 30, 2023, 10:10 AM EDT

Dear Char Rae,

 

Thanks for the links to information on blight. It looks like blight could be part of the problem. Specifically, I thought some of the leaves on the plants resembled pictures of Fusarium Wilt.

 

I did dump the Early Girl Bush plant out since it was completely dead and all the fruit had matured. The soil in the bottom half of the container was definitely moist to the touch, but not soggy. I could not squeeze any water from it. The roots at the bottom of the plant looked a healthy light brown in color. They were not slimy. I have attached a few pictures.

 

I thought the Early Girl Bush was indeterminate because it was labeled that way in the garden store but when I looked it up on Burpee’s website it is classified it as determinate. We did get a lot of fruit from it all at once before it started to die. I am now wondering if its yellowing could be attributed to the fact it was determinate.

 

The rest of the plants are definitely indeterminate and none of them have new blossoms. The yellowing is increasing on the Fourth of July and sweet 100 plants. As they die and after the remaining fruit ripens I will dump them and examine their roots too. The Juliet and Abe Lincoln plants have some yellowing. I have continued to water them when the soil feels dry to the touch about two inches down.  If I use the moisture meter towards the bottom of the plant it reads dry to border line moist. The other plants all read moist to wet at the bottom of the container.

 

An interesting observation I just remembered, is that before any of the plants started to yellow I noticed that water ran through the containers and out the holes at the bottom much quicker for the Abe Lincoln and Juliet. I can’t think of any differences in the containers or soil. The containers all have the same number and size holes and the soil all came from the same bags.

 

Thanks for your help.

 

Phil Meyer

 

From: ask=<personal data hidden> [mailto:ask=<personal data hidden>] On Behalf Of Ask Extension
Sent: Sunday, July 30, 2023 10:11 AM
To: Philip Meyer
Subject: Re: Tomato Plant Problem (#0112694)

 

The Question Asker Replied August 03, 2023, 4:42 PM EDT

It had not occurred to me that being determinate or indeterminate might be affecting the health of your plants, but, as you point out, the differences might be a factor. Determinate (which are easier to grow in containers, due to their predetermined and shorter height) tend to produce the fruit at one time and then the plants die. The indeterminate tomatoes will tend to produce through the season.  The link below has interesting information about the differences and some recommendations for selection.

Despite my best efforts (I don't use chemicals), I have always dealt with some blight each year. Oddly, the plants continue to produce fruit, even when almost all of the leaves have yellowed. I have been trying to be very vigilant about making sure that none of the leaves come in contact with the ground, as they can be efficient transporters of the fungus from the ground, especially when wet. I trim the plants with scissors, trying not to touch the plants as I remove the lower stems and leaves. And, as I think I mentioned earlier, be sure to throw away the clippings, rather than putting them in your compost.

With your containers, one of the suggestions is to be sure that they are spaced so that the plants are not touching each other and there is plenty of light and air for each plant. One of the things I have not been very consistent about, but I could see you being good at, is to keep a gardening journal. Note the types of plants, when and where they are planted, and the results throughout the season. This information can then be useful as you plan your garden for the next year.

I hope you continue to enjoy the wonders of gardening!

Char





https://www.thespruce.com/indeterminate-tomato-variety-1403423

Char Rae Replied August 06, 2023, 8:07 AM EDT

Char,

 

I wanted to follow up one more time to help plan for next year.

 

I was not able to determine if the problem was overwatering  or a fungus or blight of some sort even after looking at the information on the links you provided. However, I am leaning towards the problem being a fungus because the root systems of the plants in the containers I dumped earlier looked like healthy roots based on photos that I found. I would expect plants that experienced root rot from overwatering to have root systems that looked unhealthy. Another interesting occurrence is that one of the plants that appeared completely dead has new green branches on it that have flowered. I would think that if the root system was completely dead it would not be showing this sign of life.

 

We have been using both stakes and a trellis system to hold the plants up. Branches from one plant do touch the other plants on the trellis.

 

So, I think my plan for next year will be:

1.       Wash and sanitize my containers with a bleach solution.

2.       Use new potting/vegetable soil.

3.       Water based on the weight of the container not on how wet the soil feels.

4.       Remove the trellis support system and rely on stakes for support to keep the plants from touching.

5.       Space the plants further apart. (What spacing do you recommend?)

 

Do you have any other suggestions?

 

Thanks for your help.

 

Phil Meyer

 

From: ask=<personal data hidden> [mailto:ask=<personal data hidden>] On Behalf Of Ask Extension
Sent: Sunday, August 06, 2023 8:08 AM
To: Philip Meyer
Subject: Re: Tomato Plant Problem (#0112694)

 

The Question Asker Replied September 15, 2023, 4:55 PM EDT

Hello Mr. Myer, Good to hear from you again. I have requested a second opinion, from someone who has more expertise in growing tomatoes, to make sure I haven't missed something in my attempt to diagnose the problem. I checked my sources on container gardening, but did not find anything helpful beyond what we had already discussed.

I hope that your tomatoes will be more successful next year. With your determination and interest in finding solutions to problems, I suspect you would enjoy the Master Gardener course and opportunities to help others. You can get information about the course from your local Extension Office.

Good gardening to you!

Char

Char Rae Replied September 17, 2023, 6:50 AM EDT

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