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Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 8:55 pm
by Setec Astronomy
Shule wrote: ↑Wed Apr 06, 2022 8:06 pm
@Setec Astronomy
Can you show us a picture?
What kind of softened water do you have? Some uses sodium to soften; How much sodium is in the water is a matter of concern.
What's the temperature in your growing environment?
The temp is 65-70°F. It's sodium-softened water, and it's not a huge amount because the water isn't hugely hard...just pretty hard. I've got my outside faucet turned on now so I can get unsoftened water, and I do have distilled.
IMG_2625.JPG
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 8:59 pm
by Shule
@Setec Astronomy
I'm more concerned about the leaves curling than the purple factor, in this case. Those are *very* purple, though. Curling could be caused by lots of things.
It might be the fertilizer, especially if you're not watering very much. The water to fertilizer ratio is normally recommended to be a certain balance. It might be too much fertilizer for how much water there is, I mean.
Since the plants have grown as large as they have, I don't think there's *that* much salt. So you could be okay there (still, though, the salt makes me nervous, even though it's probably in the range that is supposed to be safe for plants).
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 9:07 pm
by Shule
@Setec Astronomy
Are they blue tomatoes, or tomatoes with anthocyanin skin, by chance (like Indigo Rose, Fahrenheit Blues, Dark Galaxy, Dark Queen, Blue Berries, Dancing with Smurfs, etc.)? Those get purple foliage naturally, sometimes.
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 9:21 pm
by Setec Astronomy
The droopiest ones are Artisan Marzano Fire, that's one of them in the picture. I just gave them a good bottom-soaking with distilled water, we'll see if they've perked up any in the morning.
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 9:51 pm
by MissS
I agree with Shule that I would be more concerned about the leaf role than the color. The leaf role could be from a few things such as over feeding them or being too dry or wet and then there are mites too.
The purple is a phosphate deficiency caused by the cool temps. No matter how much phosphorous is you feed them the plants will be unable to synthesize it. No worries though, your plants will outgrow it once they get put outside in the sun and the nice spring temps.
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 10:39 pm
by Shule
Setec Astronomy wrote: ↑Wed Apr 06, 2022 9:21 pm
The droopiest ones are Artisan Marzano Fire, that's one of them in the picture. I just gave them a good bottom-soaking with distilled water, we'll see if they've perked up any in the morning.
Do you generally water from the bottom? That could also be an issue, if so. I've noticed that a lot of people who do that (with houseplants) report strange problems now and then. It could just be a coincidence.
Re: Purple undersides of tomato leaves
Posted: Wed Apr 06, 2022 11:11 pm
by Setec Astronomy
Shule wrote: ↑Wed Apr 06, 2022 10:39 pm
Do you generally water from the bottom? That could also be an issue, if so. I've noticed that a lot of people who do that (with houseplants) report strange problems now and then. It could just be a coincidence.
Well, sort of--I thought that was what you were supposed to do to get the roots to grow and to prevent any fungal disease to the plant.
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 12:45 am
by Shule
@Setec Astronomy
I wouldn't say you're supposed to do it, but it's something people can do. It probably would reduce problems like damping off, mold, and fungus gnats, though, but it might increase the chance of problems with the lower roots, and cause the upper roots to dry out. You might try checking out the lower roots to see if they look good.
If the upper roots were more moist in the past and are drier now, those might have suffered some damage and caused leaf curling. That would probably be a temporary issue, if so, since they'd probably adapt, due to the bottom water (I personally don't normally bottom-water, though).
If the lower roots are fine, I'd probably keep doing the distilled water experiment, for now, and stop fertilizing for a while. It might be that the upper roots do need more moisture, though.
Also, any time roots are damaged, plants are sensitive to strong light (it can make them wilt). That happens pretty fast, though (so, you don't need to wait days after the fact to see if it's going to wilt; root damage can result in leaf curl, though, and that can take a little longer to show up).
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 7:47 am
by Setec Astronomy
MissS wrote: ↑Wed Apr 06, 2022 9:51 pmThe purple is a phosphate deficiency caused by the cool temps. No matter how much phosphorous is you feed them the plants will be unable to synthesize it. No worries though, your plants will outgrow it once they get put outside in the sun and the nice spring temps.
I just dosed all my seedlings (from the top) with a little Mikro-Root with is a Trichoderma preparation which is supposed to help solubilize phosphates. I had meant to use it earlier, but. I also moved the two droopy ones to a heat mat I still have going for something else. So hopefully the belt/suspenders/overhead crane approach of Epsom Salt, water, Mikro-Root, no fertilizer, and some heat will cure them. Out of my other seedlings, some look great, some so-so. So we'll see what happens, still have 3-4 weeks until plant-out.
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 10:38 am
by Toomanymatoes
As mentioned, the purple is not really something to be concerned with at all. They will be fine. My seedlings are always purple and turn into great plants.
The leaf curl may be due to your lights. T5's are bright. The result is increased photosynthesis and heat, which increases transpiration. Curling the leaves protects the plant from this. I think that some varieties are just more sensitive than others. I am not sure if watering more will help or not because the transpiration rate may be higher than the rate of water uptake/transport. Anyway, just a guess and it could easily be something completely unrelated. The fact that it is only seen on a few of your seedlings suggests it is likely some sensitivity inherent with those varieties, which makes it more difficult to address (although, I do not think you need to do anything).
The more you mess around trying to fix a problem without knowing what it is, the higher the likelihood of a worse outcome. I would just leave them alone.
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 2:36 pm
by Setec Astronomy
Toomanymatoes wrote: ↑Thu Apr 07, 2022 10:38 amThe leaf curl may be due to your lights. T5's are bright. The result is increased photosynthesis and heat
The more you mess around trying to fix a problem without knowing what it is, the higher the likelihood of a worse outcome. I would just leave them alone.
These are LED's, so the heat isn't so bad, but still some. With all due respect, the reason I posted was to try and figure out what the problem is, so I could fix it. The two plants, and maybe a couple of others, were getting all droopy.
The two droopy ones look much better right now, but I'm not sure why, because I changed about 6 things at once--they are on a different shelf under T5HO fluorescents (but very far away), because that's where the heat mat was. They got a lot of water--no fertilizer mixed in. I gave them some Mikro-Root, and sprayed them with Epsom Salts.
There's another wrinkle here, I changed one of my T5HO fluorescent fixtures to LED, but since the outer bulbs are canted inwards, the fixture doesn't provide as wide a lighting area with the LED's. I had a tray of seedlings that didn't have true leaves yet that I wasn't fertilizing, but the other day I realized the light distribution was a problem so I rearranged all the seedlings and got a little mixed up about what had been where, which could mean that some of these that I'm having trouble with actually didn't get fertilized, so perhaps instead of too much fertilizer, it's uneven fertilizer--if it was the fertilizer.
Somewhere in this thread or another, in discussion about the temperature causing the purpling, and someone cited the air temp, and it was noted that due to evaporative cooling the seedlings would be colder than air temp--I can verify that with my air temp at about 67F, my IR thermometer showed 95 at the heat mat, 85 at the bottom of the Jiffy pellet, and 60 at the top of the pellet.
Anyway, here's how the same seedling looked a little while ago; you can see the one on the left has stood back up, the leaves have uncurled quite a bit, etc.:
IMG_2626.JPG
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 4:40 pm
by Toomanymatoes
Setec Astronomy wrote: ↑Thu Apr 07, 2022 2:36 pm
Toomanymatoes wrote: ↑Thu Apr 07, 2022 10:38 amThe leaf curl may be due to your lights. T5's are bright. The result is increased photosynthesis and heat
The more you mess around trying to fix a problem without knowing what it is, the higher the likelihood of a worse outcome. I would just leave them alone.
These are LED's, so the heat isn't so bad, but still some. With all due respect, the reason I posted was to try and figure out what the problem is, so I could fix it. The two plants, and maybe a couple of others, were getting all droopy.
The two droopy ones look much better right now, but I'm not sure why, because I changed about 6 things at once--they are on a different shelf under T5HO fluorescents (but very far away), because that's where the heat mat was. They got a lot of water--no fertilizer mixed in. I gave them some Mikro-Root, and sprayed them with Epsom Salts.
There's another wrinkle here, I changed one of my T5HO fluorescent fixtures to LED, but since the outer bulbs are canted inwards, the fixture doesn't provide as wide a lighting area with the LED's. I had a tray of seedlings that didn't have true leaves yet that I wasn't fertilizing, but the other day I realized the light distribution was a problem so I rearranged all the seedlings and got a little mixed up about what had been where, which could mean that some of these that I'm having trouble with actually didn't get fertilized, so perhaps instead of too much fertilizer, it's uneven fertilizer--if it was the fertilizer.
Somewhere in this thread or another, in discussion about the temperature causing the purpling, and someone cited the air temp, and it was noted that due to evaporative cooling the seedlings would be colder than air temp--I can verify that with my air temp at about 67F, my IR thermometer showed 95 at the heat mat, 85 at the bottom of the Jiffy pellet, and 60 at the top of the pellet.
Anyway, here's how the same seedling looked a little while ago; you can see the one on the left has stood back up, the leaves have uncurled quite a bit, etc.:
I apologize. I was not trying to imply you should not ask about your problem to find a solution. That is a large part of why these forums even exist. I was only trying to point out that often people "over love" their plants/seedlings and it results in a poor outcome. For example, I am not sure why you sprayed them with epsom salts. Were you assuming a Mg or S deficiency?
In this particular case, leaf curl can be caused by so many factors it will be almost impossible to get a proper diagnosis. Considering all of your other seedlings were doing just fine, that tells me that whatever you are doing is working and it is likely a sensitivity of the particular variety. I see it all the time, especially with peppers. It is just a consequence of treating everything the same.
As far as the heat was concerned, I was mostly referring to the fact that under excess light conditions plants dissipate the excess energy as heat to prevent photodamage. So, you could have two factors playing a role here - increased use of H2O due to high levels of photosynthesis and increased transpiration due to heat. Was just one of many possibilities. I also assumed you were using T5HO lights. I used to use those on my reef aquarium, so I know those things can be really intense!
Purpling is likely due to the lower temperature affecting phosphorous uptake (or is it processing? I am not sure, have to look that up). I am not sure if it is soil temperature or air temperature or both. Based on your observations, seems like it may be air temperature?
I am happy to see your little guy is doing better now though!
Re: Purple undersides of tomato leaves
Posted: Thu Apr 07, 2022 6:24 pm
by Setec Astronomy
I'm sorry, I get a little crazy about this stuff because I don't grow any extra seedlings, so it becomes a calamity if it looks like I might lose one. About the Epsom Salts--Googling purpling I quickly found 2 YouTube videos from people who have large followings (which doesn't mean they know what they are talking about) who both said that it can be helped by spraying with Epsom Salt solution. I had some so I figured I would give it a shot, nothing to lose it seemed.
I'm thinking part of my problem is that even with the LED lights, the heat/light is too intense, particularly the way this fixture upgrade went. This is only my third year growing seedlings (I think?), and the first year I didn't have enough light, so last year I went a little overboard with the 4-bulb T5HO's, and had them too close, etc. I thought with the LED's I could put them very close, etc. Some of this should be in my light fixture thread so I'm not going to go farther off-topic here.
I've backed off the lights a little bit more and in a couple more days I'll feed everything again, thin the ones that have yet to be thinned, and a few more days after that I think it will be time to up-pot and then it should be smooth sailing to plant-out.
Re: Purple undersides of tomato leaves
Posted: Fri Apr 08, 2022 8:33 am
by MissS
Setec Astronomy wrote: ↑Thu Apr 07, 2022 6:24 pm
I'm sorry, I get a little crazy about this stuff because I don't grow any extra seedlings, so it becomes a calamity if it looks like I might lose one. About the Epsom Salts--Googling purpling I quickly found 2 YouTube videos from people who have large followings (which doesn't mean they know what they are talking about) who both said that it can be helped by spraying with Epsom Salt solution. I had some so I figured I would give it a shot, nothing to lose it seemed.
I'm thinking part of my problem is that even with the LED lights, the heat/light is too intense, particularly the way this fixture upgrade went. This is only my third year growing seedlings (I think?), and the first year I didn't have enough light, so last year I went a little overboard with the 4-bulb T5HO's, and had them too close, etc. I thought with the LED's I could put them very close, etc. Some of this should be in my light fixture thread so I'm not going to go farther off-topic here.
I've backed off the lights a little bit more and in a couple more days I'll feed everything again, thin the ones that have yet to be thinned, and a few more days after that I think it will be time to up-pot and then it should be smooth sailing to plant-out.
I have found that with using the LED lights that I do not need to keep the plants so very close to the lights. If I do then they become stressed and look very similar to yours. Once I backed off the lights some my plants were fine. So that is a very good notion on your part.
Re: Purple undersides of tomato leaves
Posted: Fri Apr 08, 2022 8:54 am
by Setec Astronomy
MissS wrote: ↑Fri Apr 08, 2022 8:33 am
I have found that with using the LED lights that I do not need to keep the plants so very close to the lights. If I do then they become stressed and look very similar to yours. Once I backed off the lights some my plants were fine. So that is a very good notion on your part.
I'm not taking credit for the "good notion", I'm going to credit the fine people of this forum for all their help. And due to your post, I just ratcheted up the lights another notch, LOL.