Growing tomatoes in the PNW. Help please!

Dallas, OR(Zone 8a)

I hope someone can help me identify what is going on with several of my tomato plants. Some of the outer larger leaves have the "spots". They look like some type of bug is biting ,but i see no bugs . I removed all the effected leaves and the plant still looks very healty and is setting fruit. My picture is the underside of the leaf and the "bites" appear to be a silvery gray color. Any advise greatly appreciated and treatments if needed most welcome. Thanks

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Salem, NY(Zone 4b)

Although they may look like bug bites I don't recognize them as same/

what do the upper side of the leaves look like?


Cherry Grove, OH(Zone 6b)

Look up "four lined plant bug" and see if that looks familiar.

Dallas, OR(Zone 8a)

Carolyn, the top of the leaves kinda look like black spot but lighter in color. I have discarded all the effected leaves and the plant seem to be looking better today. Some of my roses have black spot due to our rain, so maybe that is what it is and just looks different on the tomato. Growing tomatoes in OR is challenging to say the least.( California native) Warm weather is coming so that might help.

Steve, Thank goodness that bug does not look familiar. Ugly!

Thank you both for your input. :)

Liberty Hill, TX(Zone 8a)

I have had a very similar issue. If you could take a picture of the top of the leaves it might help. When looking only at the top of the leaves it looks like a disease BUT then I saw something was eating the tissue on the underside of the leaves, so that part of the leaf was thinner and it was very noticeable in the daylight. I took picture outside, removed the leaves and took pictures inside, they looked completely different I would have never thought they were different until I took the pictures in different lighting.

Ill see if I can find the pictures and my notes. Anyway, I believe it was either a small worm or thrips but I cant remember ATM. lol However looking at the top of the leaves definitely looked like a fungal issue. You might try googling Black Spot on Tomato Leaves and see if it looks familiar. I think if you check the underside of your rose leaves you wont find those Bite marks.

Salem, NY(Zone 4b)

Black Spot of Roses is caused by a completely different fungus than what can infect tomatoes. And there is no disease named Black Spot of tomatoes, but there are two foliage diseases of tomatoes that do have black spots on the upper leaf surface: Bacterial Spot and Bacterial Speck.

Which is why I'd still like to look at what the upper leaf surface looks like.

Yes, I do know about the challenges of growing tomatoes in OR, but I also know Mike Dunton very well and he's the owner of Victory Seeds in OR and he and a few others I know seem to do quite well with their tomatoes.

I'm glad others have chimed in to help. The problem I have is that sometimes I can post using this browser and sometimes not, and when I have to switch to that other browser sometimes I forget to do that.

When I'm perfect rest assured I'll tell everyone about that. LOL


Dallas, OR(Zone 8a)

Sadly, I found some new leaves this afternoon once the rains stopped. These are from an Early Girl variety. The other plants seem OK so far.
I did google Bacterial spot & speck and it could be it although I don't not see any thrips. Or do they come out at night? Pic below of top side of leaves picked today. Back side looks the same as my first post.

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Liberty Hill, TX(Zone 8a)

Thats what mine looked like too. It appears as of the damage is on the the top surface of the leaf until you turn the leaf over..and see the damage is actually on the underside.

The point I was trying to make about the rose leaves is that the damage you see is probably not visible on the underside, like on the tomato leaves. You may want to try googling thrip damage on tomato leaves. I know I read somewhere that the damage on the underside of the leaf causes the appearance of disease on the upper leaf surface.

I do remember that I sprayed with neem oil a couple of times and the problem didnt continue. The new growth looked normal. This was last year and the conditions were so hot and dry that I didnt get many tomatoes. Obviously, I let mine go a little longer before I took pictures.
This message was edited Jun 7, 2012 2:26 PM

This message was edited Jun 7, 2012 2:30 PM

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Salem, NY(Zone 4b)

No, the upper leaf surface is neither Bacterial Speck nor Spot.

Thrips transmit Tomato Spotted Wilt Virus (TSWV), not the bacterial foliage diseases which are spread by wind and rain and also by splashback infection if a person's plants have had the same infection the previous year and the bacteria have dropped to the ground and can splash back on thelwoer folaige when it rains or with irrigation.


Dallas, OR(Zone 8a)

Well I am baffled. These plants are all from a local nursery, planted in pots with fresh potting soil/compost up on the deck. It's crazy. I do have some neem I may try that to see if it helps. Plan B will be to buy my tomatoes at the local farmers market when they become available. Geeze!

Oceanside, CA(Zone 10a)

I see that all the time on lower leaves in the spring. Not a's a caterpillar of small stature. Could be baby loopers or some other kind of baby caterpillar(they're very tiny). They eat until they hit the leaf membrane and stop....then start in another area. I've never had to do a thing about it. It seems to stop after a month or so.

Dallas, OR(Zone 8a)

Hope that is all it is Ray. I am just about dying for a good home grown tomato. Supermarket tomatoes are the worst!

I appreciate all of you for your expertise. Growing tomatoes when I was in California SF bay area was a no brainer. This wet weather really changes my gardening ways. I do have a 5'x5' pop up green house which never got set up this year. Next year for sure and hand watering at least until July when we can count on dry weather.

Liberty Hill, TX(Zone 8a)

Ok, I remember showing the above picture and some others to Ray last year. He told me then it was a tiny caterpillar. I thought it might be thrip damage, not the TSWV that they can give to the plant, just the damage that they do.

I remember it came on really fast. My garden is directly out my side door I opened the door one morning and the damaged plant was very visible. I kept looking at the top of the leaf, realizing I had seen this to different degrees before. Then I turned the leaf over and realized THAT was where the real damage was. I sprayed neem oil but have never lost a plant to it. If your gardening is on a deck in pots and it's not an airborne disease then it makes sense that it's the small larva of a moth (that can fly) are any of the leaves curled in on themselves? I'm going to have to google this, I did last year and was certain I had found the culprit but I can't remember now. Lol

I thought it was pretty wet in the SF Bay Area? I'm from So Cal and gardening was a no brainer. But what I see in you pics looks so familiar.

Dallas, OR(Zone 8a)

Parts of the Bay area are rainy during winter, but by spring most counties are pretty nice. I have lived in all and never had any problems with tomatoes,except an occasional vist from those ugly big tomato worms. As it is becoming dusk now, I went out to inspect the plants to see if any night time critters were present. Saw nothing. Maybe the garden faries are playing tricks me. I have about a quarter acre lot & pond to tend to, but the tomatoes are in pots up on the deck as the soil is very soggy clay during rainy season and dries to a very sandy grit when dry. (fast draining in the summer.) I have brought in truck loads of compost and have had truckload of the clay hauled away. In time I hope to get all veggies in the ground as the soil conditions improve. Dry forcast is expect this weekend so I will try the neem when the plants dry a bit.
Pic of my Chihuahua named Blossom near my sad tomato plants and a few of the pretty Bearded Iris that made it thru the last rain.

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