HELP: another year of slow-growing (tomato & pepper) seedlings


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Hello Gardening Friends

It’s another year of slow-growing tomato (and pepper) seedlings for me and I’m looking for advice on getting a better system going.

I’m now about 5 weeks in and my seedlings still don’t have their first true set of leaves:
File May 01, 8 54 13 AM.jpeg


I am using coconut husk seed-starting media and a heat mat. I planted a mix of heirloom tomato seeds, some husk tomato seeds, and a mix of hot pepper seeds in late March. As in past years, after the seedlings initially sprouted I turned off the warming mat and turned on a florescent light fixture which I hang a few inches above the seedlings.

This year I actually upgraded my lighting rig from a basic shop lamp with inexpensive bulbs to an “AgroBrite,” grow-light specific setup. That doesn’t seem to have changed much the slow-growing seedlings that I seem to experience every year.

I seemed to get a quick initial start to my heirloom tomato seeds after just a couple of days. The pepper seeds took 10-14 days to initially sprout, and the husk tomatoes took at least another week after that to begin poking up through the soil.

But nothing has yet grown its first true set of leaves (first image below), the husk tomatoes seedlings are tiny (second image below), and the pepper seedlings are turning a bit brown/black (third image below). (Note: I JUST watered the trays which is why they look pretty moist in these photos.)
File May 01, 8 54 23 AM.jpeg
File May 01, 8 54 43 AM.jpeg

File May 01, 8 54 33 AM.jpeg


I know watering is an important variable. I water my seed-starting trays from the bottom and wait for the media to visibly appear dry before I add more water to the bottom. The following image shows on the right the level of dryness I wait for (these are the pepper seedlings) and then circled on the left (these are the husk tomato seedlings) what the soil looks like after it’s been watered:
InkedFile May 01, 10 30 30 AM_LI.jpg


I have had very similar slow-growth for the past many years. I used to think it might be the cool temperatures on the porch where I used to start my seedlings, but I moved over the winter and so this batch is in a new basement location that is definitely warmer, yet still my seedlings seem to grow much more slowly that they should. And again I also tried a new lighting system as well this year.

Any advice and guidance would be most appreciated.

Thanks,

-=RR=-
 
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It is easy to get seeds to germinate, all they need is warmth and moisture.

You have proved that.

It is what you do next is important, a basement is no good ,they need more warmth and natural light.

All they are doing now is growing slowly towards artifical light.

I would not start so early,it has given you no advantage at all.
 
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Agree.
Where do you live/USDA growing zone? That's really an important factor in answering any garden question.

Start getting them outside if you can. No full sun obviously, at first.
 
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What is the mats temperature and what is the ambient temp? If the mat is +/-80F and the ambient temp is above 70F it is not the temp. It looks as if the light bulb is slightly too high above the seedlings but what I think the main problem is the growing medium. I say this because of the purpleing of the stems and underside of the seed leaves. Also the leaf curl is a sign of some level of nutrition problem. Notice how the only problem, except rapid growth, only affect the larger seedlings. This is also a sign of a nutrition problem. I would change the potting mix and start over. I would use a mixture of 50/50 fine particle compost and organic potting mix.
 
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Your growing medium has no nutrients.
Change to seed compost or add some.
The problem is that the plants only have the energy inherent in the seed, and that is only enough to get the cotyledons out.
They are unable to do anything after that, and the lack of nitrogen is shown by the purpling of the seedlings.
By five weeks, especially if you use grow lights, your plants should be near ready to go in the ground. (6-8 weeks)
 
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Your growing medium has no nutrients.
Change to seed compost or add some.
The problem is that the plants only have the energy inherent in the seed, and that is only enough to get the cotyledons out.
They are unable to do anything after that, and the lack of nitrogen is shown by the purpling of the seedlings.
By five weeks, especially if you use grow lights, your plants should be near ready to go in the ground. (6-8 weeks)

I was thinking the same thing. I planted my seeds exactly six weeks ago today. They have been under a shop light (16 hours per day) the entire time, and in an unheated basement. I did germinate on a heat mat, but shut it off once they all sprouted.
Started them in vermiculite, and transferred to individual pots of potting mix once the leaves unfurled. I water them with fish tank water when the leaves start drooping.
Took this pic today...
20170501_162204.jpg
 
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Agree.
Where do you live/USDA growing zone? That's really an important factor in answering any garden question.
Start getting them outside if you can. No full sun obviously, at first.

Thanks for the quick responses everyone.

@Beth_B, I live in coastal CT - zone 7(a).

@Plantdoctor, my basement is really the only obvious place to set up a 16-hour-a-day lighting rig. At this point the temperature down there probably fluctuates from daytime highs in the low 70s to overnight lows in the high 50s.

So what should I do with the seedlings as they are now - transplant them immediately into more "nutrient-rich" media?

Thanks again all,
-=RR=-
 
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I was thinking the same thing. I planted my seeds exactly six weeks ago today. They have been under a shop light (16 hours per day) the entire time, and in an unheated basement. I did germinate on a heat mat, but shut it off once they all sprouted.
Started them in vermiculite, and transferred to individual pots of potting mix once the leaves unfurled. I water them with fish tank water when the leaves start drooping.
Took this pic today...
View attachment 19936

Don't rub it in, @Tmheldt78. Nice plants! :)
 
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Thanks for the quick responses everyone.

@Beth_B, I live in coastal CT - zone 7(a).

@Plantdoctor, my basement is really the only obvious place to set up a 16-hour-a-day lighting rig. At this point the temperature down there probably fluctuates from daytime highs in the low 70s to overnight lows in the high 50s.

So what should I do with the seedlings as they are now - transplant them immediately into more "nutrient-rich" media?

Thanks again all,
-=RR=-
If you move them on now,you run the risk of losing some, just don't handle the stems, they are just small seedlings.

I just wonder how many plants you need,that is a lot of tomatoes. :p:p:p
 
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Don't rub it in, @Tmheldt78. Nice plants! :)

Thanks! That wasn't my intention at all haha!
Trust me, I had plenty of failed experiments last year that I won't be sharing pics of. :whistle:
It just seemed like we have fairly similar setups, so I was trying to eliminate variables.
Mine are in an unfinished basement, and havent seen the light of day yet, so it almost has to be the growing medium.
Like Plantdoctor said, try not to handle the stems at all. I grabbed mine by a leaf and slid a toothpick underneath to pop them out when I transferred them to the 4-inch pots.
Good luck!
 
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Thanks for all your helpful suggestions everyone. I thought that sterile coconut husk seed starting mix was the organic way to go. I hadn't realized it had no real nutrients in it: I wish it was more specific on its packaging. Anyway, I just wanted to update you all that after transplanting my seedlings into a nutrient rich soil most everything survived and magically sprang to life. Thanks again! (By the way, would something like this be a better choice for future years? http://www.gardeners.com/buy/organic-seedstarting-mix/37-808.html)
 
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Thanks for all your helpful suggestions everyone. I thought that sterile coconut husk seed starting mix was the organic way to go. I hadn't realized it had no real nutrients in it: I wish it was more specific on its packaging. Anyway, I just wanted to update you all that after transplanting my seedlings into a nutrient rich soil most everything survived and magically sprang to life. Thanks again! (By the way, would something like this be a better choice for future years? http://www.gardeners.com/buy/organic-seedstarting-mix/37-808.html)
Just liquid feed them each week till their big enough to transplant into the garden or pots with plenty of nutrients.
Some looking a little leggy...searching for light.
Not a problem though.
You can plant them fairly deeply.
Best of luck.
 

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