What is this and how do I treat it?

[ScottWhatty]

Living in San Diego and have yet to ever see something like this. Does anyone know what this is and how to treat it?

[rainbowgardener]

Several possibilities including some (probably viral) disease, but off the top of my head it reminds me of herbicide damage. If maybe your next door neighbor sprayed 2,4D or some other plant poison and it drifted over into your yard:

"Tomato plants are highly sensitive to herbicide exposure and the result is twisted, curling leaves." https://bathgardencenter.com/herbicide- ... to-plants/

[catdaddy66]

Are the spots on my tomatoes' leaves indicative of a virus? Or is it a nutrition issue? Just don't know much about this kind of thing...

[catdaddy66]

Another view...

[catdaddy66]

And, as an added bonus, in the background you'll notice the 4 legged members of the garden gang!

[applestar]

Cute paws


…I think those spots look like septoria — a fungal disease.

Cut off all the leaves below the fruit truss, leaving about 1/2 of leaf stem on the trunk. (These will dry up and fall off on their own)

The leaf opposite the fruit truss can be cut off too — I’m following this protocol after watching Japanese gardening videos that said this leaf can divert calcium from the developing fruits, and removing it soon after fruit set can help prevent BER (blossom end rot).

Start spraying your tomato plants to prevent fungal disease from getting foothold. At least once a week, twice a week is better, alternating between biological and chemical.

I prefer 1:8 diluted milk and whey in de-chlorinated water, or 1:10 AACT (actively aerated compost tea), or 1:200 eggshell vinegar {crushed eggshells steeped for 24~48 hours in grain (rice) vinegar -then strained into a glass storage bottle-} for biological. …And potassium bicarbonate 1Tbs in 1 gallon with a dribble of liquid soap and few drops of oil (canola … this year using neem supplemented canola) for chemical. Baking soda (sodium bicarbonate) can be used instead and is more common recipe, but spending for potassium bicarbonate will add potassium as foliar supplemental nutrient).

I also spray peroxide (dilution?) directly on fungal spots if I’m trying to keep the leaves, but more likely to clip off affected leaves.

[catdaddy66]

Cute paws


…I think those spots look like septoria — a fungal disease.

Cut off all the leaves below the fruit truss, leaving about 1/2 of leaf stem on the trunk. (These will dry up and fall off on their own)

The leaf opposite the fruit truss can be cut off too — I’m following this protocol after watching Japanese gardening videos that said this leaf can divert calcium from the developing fruits, and removing it soon after fruit set can help prevent BER (blossom end rot).

Start spraying your tomato plants to prevent fungal disease from getting foothold. At least once a week, twice a week is better, alternating between biological and chemical.

I prefer 1:8 diluted milk and whey in de-chlorinated water, or 1:10 AACT (actively aerated compost tea), or 1:200 eggshell vinegar {crushed eggshells steeped for 24~48 hours in grain (rice) vinegar -then strained into a glass storage bottle-} for biological. …And potassium bicarbonate 1Tbs in 1 gallon with a dribble of liquid soap and few drops of oil (canola … this year using neem supplemented canola) for chemical. Baking soda (sodium bicarbonate) can be used instead and is more common recipe, but spending for potassium bicarbonate will add potassium as foliar supplemental nutrient).

I also spray peroxide (dilution?) directly on fungal spots if I’m trying to keep the leaves, but more likely to clip off affected leaves.

Thanks for the info! I'm slowly learning about plant health and disease prevention. I had actually scrubbed these pots before potting the plants, but I guess detergent wasn't enough to prevent the issue.

[imafan26]

I agree with the leaf spot disease. It looks more like bacterial spot than septoria by the shape of the necrotic patches. Some look like more alternaria leaf spot because they are more irregular in shape. It is common in humid wet weather. Whichever disease it is, the treatment will be similar.

The curling could be herbicide but the other leaves look fine. If this is mostly at the tip, I would get a good hand lens and look for mites or thrips. They like to deform and curl young leaves especially at this time of the year. For me, mites are more common than thrips right now. I have broad mites which are very difficult to see unless you have high magnification and a lot of patience. Spider mites are easier to see, but they cause bronzing under the leaves and the broad mites like to deform very young leaves.

https://plantclinic.tamu.edu/2013/09/20 ... -tomatoes/
https://www.plantanswers.com/articles/spidermites.asp
https://aggie-horticulture.tamu.edu/veg ... ia-canker/
https://aggie-horticulture.tamu.edu/veg ... leaf-spot/
https://aggie-horticulture.tamu.edu/veg ... ial-speck/

Fungal disease is better prevented since cure is hard. For mites and thrips, the same thing will work for the mites as well as for fungal disease. I use 3 in 1 spray. It contains sulfur which is a fungicide as well as a miticide and pyrethrins. The only thing is you have to read the label and follow the directions. Do not spray in the heat of the day and especially if it is going to be a scorching heat. Spray under the leaves to kill the mites. I usually cut off the infested branches. They will never get better. Pull off all the infected spotted leaves. Fungicides have to be used prophylactically, weekly, while the warm humid conditions persist and resprayed after a rain. I have been using hydrogen peroxide as well as a preventive fungal spray. It is 3 tablespoons in a quart. It kills fungal spores on contact but does not have any curative or lasting qualities. Systemic fungicides work better at cure, but I don't like to use systemics on edibles.

[catdaddy66]

Not sure what this discoloration is but it was on a brandywine tomato plant. I was hoping to trim the affected leaves but had to call the plant ultimately.

[catdaddy66]

Not even sure what this is but it's ruined 6 of 10 squash plants.

[catdaddy66]

And these are the rest of the affected plants...

[applestar]

It’s hard to diagnose just from distant photos, so these are first impressions and thoughts —

(1) the tomato — common problems start from bottom up — oldest leaves closest to the ground. But at first glance, the problem seems to be on upper leaves like a surface splash or spray… older leaves appear to be green…?
— if only young topmost growths were affected, there are viruses as well as systemic herbicides that could affect, but that doesn’t seem to match either. Defiantly need more info/details

(2) “squash” — what kind? First suspect for C.pepo and C.maxima exhibiting wilting new leaves and yellowed lower leaves is SVB (squash vine borer)

(3) is that straw mulch? Must also suspect herbicide contamination…. Easiest test is to try growing some kind of legumes like peas or beans in same area.


Need more info and details.