Some of my tomato seedlings look bad

[nickdu]

I've started a bunch of tomato seedlings. Some of them look pretty bad. They didn't look bad always, but they look bad now. I keep the seedlings under my t5 6500k bulbs 24/7 and they are indoors. I'm wondering whether it could be overwatering, but I think I treat all the seedlings the same yet some look ok and others look worse. I only water probably every second or third day. They are in 3.5" square pots with holes in them so the roots are not sitting in water. I water them until the water is coming out the bottom and them put them back in the tray.

Here is a picture of a bunch of the young plants:

You'll notice a couple on the left looking pretty sickly and one in the back. Here is a close up of the bottom left plant.

I also have this one which got bigger and I transplanted to a 9x9 pot and keep outdoors as long as the weather is not too cold. We had a couple chilly days of rain and I'm wondering whether that was too much for the plant. Notice the curled up yellowish leaves.

Any suggestions? By the way, the roma's seem to do better than the beefsteak. Not sure if that's typical. I'm also wondering whether being under the lights 24/7 is not good. I did read articles which seemed to indicate that 24/7 lights are ok for the first 6 weeks or so. To be honest, I'm not sure how old these are.

Thanks,
Nick

 

[Becky]

The soil looks pretty wet, so overwatering would be my first thought. I'm certainly no expert in this area though, so hopefully someone else will be able to shed some light on this!

 

[nickdu]

Thanks for the reply. I'm surprised you think it looks pretty wet. While there is some moisture in it, I wouldn't call it wet. As I mentioned, the pots have holes in them so the water drains through. After watering I let the pot drain into the sink and then put it back into the tray. There only water in the tray is from the few drops that continue to drain from each pot after watering. How often do you water your plants?

Just last night I turned off the lights. I think I'm going to start giving the plants a sleep cycle each night and see if this has any impact.

Thanks,
Nick

 

[Sheal]

I would imagine that it's to hot under the lights for the tomatoes now Nick, especially as they are indoors. I'm not aware of the temperatures where you live, but tomatoes will suffer from heat as well as cold. The first thing that usually determines that is the fact the leaves have turned purple underneath, although this is usually more common if the plants are cold. Your tomatoes are big enough to remove from the lights but they won't be happy in a temperature less than 7C/45F, night or day.

Check the base of the pots for roots, looking at the height of them I would think most need potting on. A gradual process is best with pot size, I pot mine on from a 3 inch pot to a 5 or 6 inch, from there they will go into buckets in my greenhouse, I can't grow them outside. I only water pots when they are almost dry and that can be determined by the weight. The plants may also have used up all the nutrients in the soil, which only lasts for six to eight weeks. If they are staying in their current pots then give them a weaker than usual tomato feed, if they are being moved on then new soil will be enough.

However, one stage at a time, give them a few days away from the lights and see if they start to pick up, if not try feeding them or potting them on.

 

[nickdu]

Thanks. In terms of the purple underside of leaves and purple stems, yes, mine have the purple leaves and stems. I have read that this can be caused from cold temperatures. In fact I just recently replied to a post regarding that saying that I didn't think it has much to do with temperature, certainly not cold temperature, but instead was due to light. That's my uneducated guess as it seemed my stems started turning purple as soon as I got the seedlings under the lights. Also, my lights don't give off much heat, they are t5 bulbs and a few inches away from the bulbs you really can't feel any heat from them.

The seedlings started in roughly 2x2x3 50 plug tray. I had transplanted them to the 3.5" square pots. I'm using fox farms ocean forest as potting soil so I'm guessing they have enough nutrients until they go into bigger pots. I don't think the weak looking ones are going to make it. They almost look dwarfed where the stem tapers abruptly at the top.

Thanks,
Nick

 

[Sheal]

I've just had another thought. Are you giving them cold water? Being under lights it may be putting them into shock!

Give the weaker ones a chance, they may well pick up away from the lights.

 

[nickdu]

I believe each time I watered them they got luke warm water. Once they get big enough to go outside then I water them from the watering can which I fill up from the spigot, so at that point they're getting cold water.

Thanks,
Nick

 

[headfullofbees]

If you think there's a possibility it may be too much water, then that's almost certainly it.
The way you describe watering them:

I water them until the water is coming out the bottom and them put them back in the tray.

Sounds like that would be plenty for a week.
The soil is supposed to practically dry out before watering again.
Sorry friend, but my advice is start again.

 

[Sheal]

Okay Nick, keep us posted on their progress please.

 

[nickdu]

Ok, thanks for the replies. I have a bunch of tomatoes which are good. Don't think I can start a new batch as it's pretty late in the season to be starting tomatoes from seed I think.

Nick

 

[pixie N.C.]

What are t5 lights(hps,mh or fluorescent) and why 24 hrs. I don't know much about growing with lights,but thought that changes in amounts of light creates plant change ?

 

[nickdu]

t5's are the latest, I believe, in flourescent. The ones I have are the daylight version, 6500k, so I guess the plants are getting the spectrum on light they need, or at least the best that can be offered by the latest flourescent technology. The are also very efficient, they don't produce a lot of heat.

24 hrs/day is because I'm a bit behind schedule and I also read that there seemed to be a benefit to keeping the lights on continuously at least for the first 6 weeks or so.

I'm not that familiar with growing with light either. My concern was that maybe the plants needed a "sleep" cycle just like we do. While some of the posts I read seemed to indicate that they don't in the early stages, I'm not convinced of that yet.

I think it was my second batch of seedlings that turned our really leggy. Maybe 3" seedlings with just the cotyledons. I was told this is because the plants were stretching to find light. That's probably the case because it was during a cold spell we were having so I wasn't taking the plants outside during the day and I had not received my lights yet. Also, the next batch of seedlings I started which I had under the lights as soon as they sprouted didn't get leggy at all. So this seems to make sense. However, maybe plants stretch during dark hours and maybe they need to stretch in order to grow. If I have the lights on 24/7 I may be stunting the growth of the plants. Just a thought.

Thanks,
Nick

 

[pixie N.C.]

Yea ya know when I first started gardening I used to plant seeds indoors before last frost date,and used fish tank and original fluorescent lights,before I realized that at a 7 zone just plant outside,unless it's a early plant,and I'm not that experienced yet,I'm going to try some late stuff this year,as far as lights,i'll have to learn more about,thanks for the info

 

[nickdu]

I am going to plant most of the seeds directly in the garden. The only ones I'm starting indoors are the ones which have a longer time to harvest, at least I think that's how I ended up picking tomatoes, cantaloupe and peppers. I could pick up the plants at a garden center but I wanted to start them myself by seeds.

Thanks,
Nick

 

[Norm]

Grow lights shouldn't be on 24 hrs. They should be off atleast 6 hrs a day per a grow light mfr's instructions.

My $.02