Vanisle_BC
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What's wrong with these tomatoes?

toms2.jpg
Other fruits on the same plant are unaffected - so far? At first I thought it was just cracking - now not so sure. It's been a 'funny' year; cool & very wet spells alternating with hot & dry, but generally cooler & wetter than normal. These are the Longkeeper variety.

imafan26
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Concentric cracking is from uneven watering. Alternating heavy rain followed by dry spells. It also looks like sun scald. The black parts can be a result of watering problems or necrosis from sun scald.

If you don't have good leaf cover on hot days the fruit will get sun burned. Uneven watering is a problem and it is hard to control the weather. I found it is easier to grow tomatoes in SIPs or wicking buckets. Cover the top of the container with plastic bag to keep rain out. SIP will provide even moisture. Tomatoes need good leaf cover in summer. Pay attention to pruning staking and shading. In wet. humid weather you will need to step up anti fungal sprays if you don't have a disease resistant variety. Sometimes there is nothing you can do to fight nature. Plant at the right time of the year for your location. If you can grow tomatoes in a hoop house it can help control some of the environmental issues.

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applestar
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Have you had a hotter/drier season than usual? I’m recognizing or think I’m recognizing some indications of mite damage — both signs in the stems and the russetting/corking on the fruit? If you have a microscope or high power loupe, try Making a slide by applying a clear shipping tape, folding sticky sides together, then examining.

Also, possibly physical injuries made by critters like rodents — scratching or nibbling?

Vanisle_BC
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Thanks, applestar & Imafan, for the clues to my tomato problem. I haven't yet tried the loupe exam but I'm thinking sunscald and uneven watering may be to blame. I have other plants of the same variety in my "usual" covered & part-shaded bed. Those ones are looking OK. These not-so-good ones are 'extras' that I put in an uncovered place with no shade. They got all the sun that shone, plus intermittent heavy rain on some pretty cool days. We're having a couple more days of mid-30s Centigrade now - about 95F - so I'd better give them some shade. Incidentally I was surprised the other day to notice how much shade is provided by even a fairly open plastic mesh. Here's a picture, I measured the shade as about a full f-stop (EV) darker than the grass around it:

Shade.JPG

imafan26
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Shading helps in extreme climates. I use trees, shade cloth, lath, other plants and location to help mitigate effects from the sun. I also plant heat resistant varieties as much as possible. They have thick leaf cover and I cage instead of prune so I keep most of the leaves. I have grown long keeper before. It is a nice tomato and it does keep for a long time.

Mites can be a problem in hot dry weather. On fruit, the scarring is usually near the cap. On the leaves you look for stippling. Spider mites would cause bronzing under the leaves. Broad mites, you would not see, but you need to be able to identify the damage.

It is hard for me to imagine that it can be hotter in the northern lattitudes than it is here. It can get over 100 degrees in some places like at the airport, Waikiki, Waianae, and Waipahu in August where there is a lot of asphalt and concrete. I have not seen temperatures higher than 91F off concrete, and usually where I am it is 4-5 degrees cooler anyway. The lowest temperatures are in January at around 51 degrees at night. High humidity and an ocean environment mitigates temperatures. It is more steamy than dry heat. It can feel hotter but it rarely is. My day length is shorter too so the longest day is just 13hrs and 18 min and the shortest is 10 hrs 41 min. Only a couple of hours of difference, but it matters when it comes to growing plants that depend on day length and temperature. On your hottest days, you will also have more hours of sunlight so less relief there as well.

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Gary350
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I have bought 6 pack tomato plants at the garden store and have 1 of those plants grow and act like it is not related to the other 5 plants. I have babied plants hoping they might get better but still they grow worthless tomatoes all summer. I figure if only 1 plant in the group is doing crazy things the problem is not bugs or blight. Sun burn turns my tomatoes white color on top, I pour muddy water on tomatoes to protect them from sun burn.

Vanisle_BC
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Gary350 wrote:
Mon Sep 14, 2020 9:49 am
I have bought 6 pack tomato plants at the garden store and have 1 of those plants grow and act like it is not related to the other 5 plants.
Well Gary I don't have to buy at the garden store for that to happen ! Haha, my labeling must have been so screwed up this year, I must rely on 'facial recognition' to tell my plants apart. In some cases that's impossible, but I do have one designated Sweetie that is almost certainly the odd-shaped Russian Purple I'm trying for the first time. In general I daren't save seed this year: I couldn't be sure what I'm saving. Lucky I still have earlier seeds - I hope THEY are not mislabeled.

I start my plants in soil blocks (small cubes) that are difficult to label. I can raise 60 plants on a Betty Crocker cooking tray - 10 rows of 6 - and I use a paper chart to identify their locations on the tray. This is (obviously!!) prone to error, especially when potting up but it's the best I've come up with so far. The soil blocks are too small & vulnerable to have any kind of label pushed into them.

As for the ugly 'diseased' tomatoes in my picture, the plant they are on also has healthy fruits so I think the problem is environmental, not with the plant's genetics. Other more-shaded plants from the same batch of seed are all OK.

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

I've been there too. I had plants that were obviously not as advertised on the label. It happens with seeds too. I bought papaya seed and there were bitter melon seeds inside instead. Most of the time though, especially when I plant seed, the mislabeling is my fault. I either tagged the wrong plant or the label fell out and I put it in the wrong container. For peppers, it can be a problem, since I can't tell what they are until they start fruiting. The bell peppers for the most part look alike anyway.



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