Why are my plants turning yellow? (split from mdvpc's "latest disease" topic)

liannenc · June 25, 2009

I've posted a few times in mdvpc's topic about problems with what appears to be salt damage. I thought this might be the case for me, too, and I did try one Clearex treatment a week ago. I thought that the yellow had stopped progressing, but within the past couple of days I realized I was wrong.

My hardest hit plant is Carmello, with Marianna's Peace showing a fair amount of leaves yellowing and dying also.

I also wondered if it might be herbicide damage-- Carmello not only had the yellowing but also appeared stunted, and my Paul Robeson which was on the same side of the deck as Carmello also appeared stunted (but no real yellowing on that one). My husband sprayed Round Up in our yard about 30 feet from the deck not long before I noted these problems. He's insistent he was very careful to do this on a calm day and I'm sure he was, but I know he can't totally control that the stuff still might drift somewhat anyway. I also think one of our neighbors may have sprayed recently as well.

However, Marianna is on the opposite side of the deck, and except for the yellowing, appears fine-- no stunting, and setting fruit like mad. Carmello has set a few fruit, Paul Robeson has set none.

At this point I'm at a total loss. Overwatering? Underwatering? Disease? Salt Damage? Too much or too little fertilizer? I just hate seeing the Carmello looking so sickly, and I'd rather not lose the plant.

I'm going to attach pictures and see if anyone out there has any ideas or suggestions. The ones that appear darker were taken early this morning, and the lighter ones this evening. Most of the pics are of Carmello and Marianna's Peace, and I'm also attaching one of Paul Robeson. In the morning pic Marianna, you can see how well it's been setting fruit. I'm mainly including the one of Paul Robeson to show what I think is stunting.

I'm growing in coir in grow bags and used Plant-tone initially when I set out the plants, and have alternated Plant-tone and Tomato Maker to top dress. Also have watered a few times with fish emulsion and liquid seaweed added to the water. Any thoughts??? Any questions or if more detailed/close up pics are needed, ask away, please!

P.S. I also have Goose Creek and so far it seems okay, but has only set a couple fruit. No significant yellowing or stunting, though.

dice · June 25, 2009

Pic 1 is definitely not happy. Looks more
toxic than anything else, but it could be
a disease. Overwatering usually does not
look quite like that to me. The leaves get
kind of feathery looking rather than rolling
up along the main stem like that. Maybe
some root disease.

Pic 2 looks like Cucumber Mosaic Virus.

Pic 3 looks like Pic 1. (Different plant?)

Pic 4 does not look that bad. I would say that the top
of the plant is robbing the bottom leaves, either of
water or nutrients. I would just cut off the dead leaves
on that one and not do much of anything else. Do you
have some convenient way to find out if it is drying out
really fast?

I could not see severe problems in pics 5 or 6.

liannenc · June 25, 2009

dice, thanks so much for your reply. I should have said which pics were which plants when I posted... sorry about that!

Pics 1, 2 & 3 are all of Carmello-- the first was taken early this morning, the other two this evening. I sure hope it's toxic and not a virus... I think I would at least have a chance of nursing it through whatever it's been exposed to. I guess it wouldn't hurt for me to try Clearex again just in case it's some sort of build-up in the coir from fertilizer or something.

Pics 4 & 6 are of Marianna's Peace (4 from this evening, 6 from this morning). I'm definitely going to take your advice, because except for the yellowing it seems to be doing well. I do have a moisture meter, so I'll keep an eye on that and make sure it gets enough water.

Pic 5 is of Paul Robeson. It seems somewhat stunted to me and hasn't set any fruit at all, but I'm going to just keep an eye on it... it may just be one of those plants that's a "bad luck" variety for me!

Any other ideas or input, dice or anyone? One thing I've noted is that blossoming has really slowed down on all the plants, but I'm guessing that's the heat here... even though I selected plants that are supposed to be more heat tolerant, I guess there's just so much the poor things can take before they just stop blooming until it cools off a bit.

dice · June 26, 2009

Leaf rolling is often environmental (temperature and moisture
fluctuations). It can be a nutrient deficiency, too, but there are
so many possibilities that leaf rolling alone is not enough to pin
it down. Sometimes the nutrient that is missing is not actually
lacking in the soil, but an excess of some other nutrient is
blocking uptake of it.

Take a look at "physiological leafroll" near the bottom of this
page:

http://vegetablemdonline.ppath.corne...omWiltKey.html

That looks rather a lot like your Carmello plant.

General discussion of tomato leaf roll:

http://gardenline.usask.ca/pests/tomato.html

liannenc · June 26, 2009

Yup, that picture looks like Carmello. From that info and the other things I've read about leafroll, I'm a lot less worried about that than about the yellowing. I'm going to try another Clearex treatment this evening and take a really good look at the stem which is affected by the color change to see how far it's advanced, and if I can see any changes on it. Carmello actually has two stems coming up out of the coir, and I may end up cutting back the affected one to see if there's any change inside the stem itself. I'm hoping that I can save the other stem, even though it's definitely smaller. If it's some root disease, though, I'm sure that it probably won't make any difference ultimately and I'll lose the whole plant.

If the plant were smaller I would just pull it out of the coir to check the roots for disease, then replant it if everything looked okay. I may end up doing that anyway if it begins to look like the plant is a goner. I'm just really puzzled about this, because I haven't seen anything like it even though my parents grew tomatoes for years while I was growing up. When I get home tonight, I'm going to search and possibly post to some of the hydroponics forums-- my understanding is that by using the coir only, I'm essentially growing hydroponically. I would try to do it here at work, but most of those sites tend to be focused on "other plants" and I'm betting that most of those sites are blocked on our servers. Even if they aren't, I don't want my employer to get the wrong idea from my web browsing!

Thank you, dice, for your patience with my newbie issues! You and so many others here at T-ville are the reason that I'm not just giving up on this. In spite of the problems I've had (which I know are really not major compared to what some others here have experienced), I'm looking forward to trying this again next year... with more plants, of course!

dice · June 27, 2009

Coir has three characteristics that can come into play.
One, it sometimes has excessive salt. The Clearex should
take care of that. Two, it really holds water well. If you have
had weeks of unending rain, the soil could simply have been
too wet (although I have had plants in homemade earthboxes
that have nearly pegged my moisture meter for a month or
more that still looked perfectly healthy). Three, the pH of it
can vary widely, from around 4.5 to 6.0+. If the pH was near
the bottom of that range, that could interfere with nutrient
uptake of phosphorus (purple on the bottoms of leaves, small
root systems, fewer and smaller blossoms, eventually stunted
plants) and create toxicities of trace metals (iron, aluminum,
etc).

liannenc · June 27, 2009

I'm thinking about going by the nursery today so I'm going to try to find some pH test strips so I can see if that's part of this problem. I noted a small spot of BER this morning on one of the two tomatoes I have so far on Goose Creek, so I'm going to check pH in that container also. The coir definitely holds moisture, because my meter has shown that it's still "moist" (not wet) several inches down, even though I've wondered if I'm underwatering-- I would think that, when adequately watered, I should not be able to easily pick up the container (15 gallons) full of coir AND plant but they are usually light enough that I can do just that.

I scared myself silly last night, doing more internet research-- in doing so, I thought I'd discovered that my plant has fusarium wilt. So, I went out this morning early and cut off a mildly affected branch (I cut off and discarded the worst ones yesterday). I noticed, as I did yesterday, that when cut the affected branches off, there was NO sign of discoloration inside them.

I was relieved to find the same this morning on the branch I cut. I split the base of the branch and, again, saw no discoloration whatsoever so it looks like this isn't fusarium wilt. I don't know WHAT it is, but I noticed in handling the branch that I got black powdery stuff on my fingers so I believe it's still some kind of fungus. I went right back out and sprayed some Daconil on the affected stems and branches. THAT was interesting, because I got it premixed and it was awfully thick and gloppy-- had a hard time getting it to cover the affected parts but I did the best I could.

In the pics I've attached to this post, you can see the difference between the affected stem and the one that is (so far) still "normal". The other pics are of this morning's dissection.

I'm still at a loss, and I'm torn as to whether to keep using Daconil until this hopefully clears up, or to start using neem. I'm leaning towards Daconil, because I'm serious about wanting to save these plants.

dice · June 27, 2009

"black powdery stuff":

That should be a major clue. If it was Late Blight, the plants
would probably be dead already. Botrytis is more of gray
color. I do not know exactly what that it is, but it does sound
fungal, some kind of anti-fungal would be a wise choice.

Daconil is basically a preventative. It will not kill fungi already
actively growing on stems or leaves. So you probably want to
continue with the Neem, too.

Here is a report on powdery mildew research on tomatoes.
They did not test any neem oil products, but they did have
some results with sulfur (probably "wettable sulfur" if you
are looking for it at a garden supply or nursery). Sulfur is
probably less expensive than any of the commercial sprays
that they tested. Powdery mildew is one of the fungi that
neem oil is said to do a good job against (black spot on
roses is another).

http://www.hort.uconn.edu/Ipm/veg/htms/pmildtom.html

June 25, 2009	#2
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Pic 1 is definitely not happy. Looks more toxic than anything else, but it could be a disease. Overwatering usually does not look quite like that to me. The leaves get kind of feathery looking rather than rolling up along the main stem like that. Maybe some root disease. Pic 2 looks like Cucumber Mosaic Virus. Pic 3 looks like Pic 1. (Different plant?) Pic 4 does not look that bad. I would say that the top of the plant is robbing the bottom leaves, either of water or nutrients. I would just cut off the dead leaves on that one and not do much of anything else. Do you have some convenient way to find out if it is drying out really fast? I could not see severe problems in pics 5 or 6. __________________ -- alias

June 26, 2009	#4
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Leaf rolling is often environmental (temperature and moisture fluctuations). It can be a nutrient deficiency, too, but there are so many possibilities that leaf rolling alone is not enough to pin it down. Sometimes the nutrient that is missing is not actually lacking in the soil, but an excess of some other nutrient is blocking uptake of it. Take a look at "physiological leafroll" near the bottom of this page: http://vegetablemdonline.ppath.corne...omWiltKey.html That looks rather a lot like your Carmello plant. General discussion of tomato leaf roll: http://gardenline.usask.ca/pests/tomato.html __________________ -- alias

June 27, 2009	#6
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Coir has three characteristics that can come into play. One, it sometimes has excessive salt. The Clearex should take care of that. Two, it really holds water well. If you have had weeks of unending rain, the soil could simply have been too wet (although I have had plants in homemade earthboxes that have nearly pegged my moisture meter for a month or more that still looked perfectly healthy). Three, the pH of it can vary widely, from around 4.5 to 6.0+. If the pH was near the bottom of that range, that could interfere with nutrient uptake of phosphorus (purple on the bottoms of leaves, small root systems, fewer and smaller blossoms, eventually stunted plants) and create toxicities of trace metals (iron, aluminum, etc). __________________ -- alias

June 27, 2009	#8
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	"black powdery stuff": That should be a major clue. If it was Late Blight, the plants would probably be dead already. Botrytis is more of gray color. I do not know exactly what that it is, but it does sound fungal, some kind of anti-fungal would be a wise choice. Daconil is basically a preventative. It will not kill fungi already actively growing on stems or leaves. So you probably want to continue with the Neem, too. Here is a report on powdery mildew research on tomatoes. They did not test any neem oil products, but they did have some results with sulfur (probably "wettable sulfur" if you are looking for it at a garden supply or nursery). Sulfur is probably less expensive than any of the commercial sprays that they tested. Powdery mildew is one of the fungi that neem oil is said to do a good job against (black spot on roses is another). http://www.hort.uconn.edu/Ipm/veg/htms/pmildtom.html __________________ -- alias

June 25, 2009	#3
liannenc Tomatovillian™ Join Date: Apr 2009 Location: Zone 7b in Concord, North Carolina Posts: 76	dice, thanks so much for your reply. I should have said which pics were which plants when I posted... sorry about that! Pics 1, 2 & 3 are all of Carmello-- the first was taken early this morning, the other two this evening. I sure hope it's toxic and not a virus... I think I would at least have a chance of nursing it through whatever it's been exposed to. I guess it wouldn't hurt for me to try Clearex again just in case it's some sort of build-up in the coir from fertilizer or something. Pics 4 & 6 are of Marianna's Peace (4 from this evening, 6 from this morning). I'm definitely going to take your advice, because except for the yellowing it seems to be doing well. I do have a moisture meter, so I'll keep an eye on that and make sure it gets enough water. Pic 5 is of Paul Robeson. It seems somewhat stunted to me and hasn't set any fruit at all, but I'm going to just keep an eye on it... it may just be one of those plants that's a "bad luck" variety for me! Any other ideas or input, dice or anyone? One thing I've noted is that blossoming has really slowed down on all the plants, but I'm guessing that's the heat here... even though I selected plants that are supposed to be more heat tolerant, I guess there's just so much the poor things can take before they just stop blooming until it cools off a bit.