When to fertilize seedlings? And legginess issues

dforrest · May 3, 2016

I made a bit of a late start on my seedlings. This is my first year growing my own. So now, May 3, I've got seedlings mostly with their first true leaves, some are starting on the second set. Official time to plant out in my area is May 15th.

My seedlings have come out very leggy, especially the tomatillos! One of them is so long it's fallen over and is lying down the length of the modules and is now reorienting itself to grow upward -- don't know what kind of a plant that will grow into, but suppose the bent part will get buried anyway once I plant out.

After poking around the forums a bit, I found the cold treatment method and popped the tray out of my heated, lighted germinator and stuck them on a table outside on a south-facing balcony but which gets little to no direct sunlight. It's 10°C/50°F now, forecast high today of 14°C/57°F and low tonight of 7°C/45°F. So maybe a bit colder than ideal, but OK I think. Hope they are not too shocked by the transition from their 25°C/77°F and bright light in the germinator.

Due to space issues, there are some peppers in a few modules in the tray, I'm sure this is not ideal for them but they'll have to suck it up and be tough I suppose. I hope they don't stop growing, because I'm verrrry late with them.

Another issue I've noticed is that the green color of the leaves is getting lighter and yellower and I'm beginning to think they need fertilizing. And it struck me that I have no idea at all whether, when, or how much to fertilize seedlings.

I have a nice organic 10-9-7 with kelp and amino acids that's supposed to promote the growth phase of the plants... Should I just serve it up at regular strength for any old plant? More diluted? Concentrated? Not at all? Something else? I will undoubtedly mix in some Effective Microorganisms (from the local licensee of SDC).

I am trying to keep the soil just moist and honestly have only top sprayed once since planting the seeds. Since they've been under saran wrap and then in the germinator, the soil has stayed moist, even on top, and is just now seeming like it needs a watering.

Any advice much appreciated.

Bulldog · May 3, 2016

use half strength fertilizer in your water, but yes they will need water. I was watering my seedlings every 2-3 days but it is warmer here. They will also need some light, and transitioning them out slowly is easier on them. How many weeks old are your plants and how tall are the tomatoes? How many seedlings to what size pot? Can you post a picture

clkeiper · May 3, 2016

Leggines is due to lack of light and heat. cooler weather will make them stockier. also "brush" your hand gently over them once a day to stimulate wind or set a fan to gently blow over them. I use full strength fertilizer not everyone does, but I haven't found it to hurt them. too high of a concentration will, but that is if you don't dilute it properly. it won't hurt the tomatoes to wilt down either. I let mine sit in a perpetual state of wilt right now. It isn't time to get them in the garden and they are already 10" tall. getting beautiful, but they need to wait. I also am letting them stay cooler. You may not want to retard their growth since they aren't very big yet, but getting them to be stockier will be better for them to put in the garden.

drew51 · May 3, 2016

They like it when lows only go down to 50F, so you could probably plant out. But they need 2 weeks to get used to being outside and slowly, very slowly expose them to light. Yes bury the stems. I had room issues this year bigtime because I rooted about 25 fig cuttings. My plants are now used to outside, and night temps are at 40F. Kinda too cold, but they will not die, just be a little set back. They turn a little yellow. Still, they will grow to be fine plants. I had no choice but to boot them outside!

dforrest · May 3, 2016

I planted all the tomatoes via the Saran Wrap method 19.5 days ago.

The leggiest seem to be about 11cm/4.3" tall at the moment, two of them now "fallen giants" and only the stockiest has a stem the thickness of a thin toothpick. The average height is probably 7cm/2.75".

In the pix, keep in mind the front middle and right 6 modules are peppers and so are 2 in the middle of the second row. The rest are my tomato babes.

The soil may look drier than it is, with soil coming back from the edges of the modules, as I have been moving the tray around a lot, turning it around in the germinator for even lighting and heating. The soil is still a bit moist to the touch, even on the surface.

I did not realize that heating tomato seedlings caused legginess! Oy! Big mistake to have planted them in the same flat as peppers, which as far as I know love all the heat you can give them. But boy do they ever grow slowly.

Do you think a bit of water and diluted fertilizer is in order? They're outside now.

dforrest · May 3, 2016

And one additional question while I'm at it...

If you notice in the photos, in the two outside columns especially, there are now several seedlings that have gotten so tall, leggy and topheavy that they have lain down and are pretending to be groundcover

The two tomatillos that have "fallen" still just have their cotyledon leaves, and four or five others that are more developed but in the same situation.

What should I do?

drew51 · May 3, 2016

I myself am clueless besides burying them. The worst case of weak growth I ever saw. They need light like yesterday, well a month ago. I have them under lights before they even come up.

taboule · May 3, 2016

Assuming you want to keep the very leggy ones (instead of terminating them) bring the lights very low and close to them and transplant at the next occasion -burying the stems. Make sure you dont over water once you transplant into a bigger pot and use a light mix to avoid drowning the plant or damp off.

dforrest · May 3, 2016

I think it was too much heat, probably. They have been under cheapo LED lights about 16h/day ever since they were born. But they were in the germinator with the peppers, which I was keeping quite warm.

Or maybe the light source was too far away? A couple of portable LED strip light fixtures taped to the top of the germinator (outside) -- maybe 6" above the surface of the tray to start, and now closer to the plants as they grow.

There is not much chance I can rig up better lighting soon -- no room in our flat, so it's either back in the germinator with the LEDs strapped on top and the heat off now, or out on the balcony (indirect sun) getting some cold treatment.

dforrest · May 3, 2016

No terminating, these are the chosen ones... I just need to learn what they need and cater to them better. (Actually they are varieties I wanted to experiment with from the catalog for this year and it just wouldn't be the same to give up and go to the nursery...)

I think I might just pot them up now and/or plant them out way early.

Two week forecast says nighttime lows under 10C/50F are unlikely before May 15th, our "official" local "plant em out" date. And daytime highs mostly 20-24°C/68-75°F. Bit of sun, bit of rain. My soil is very well drained (raised bed).

The advantage is that I can plant them really deep. It will be hard for me to scare up temporary pots that are deep enough without being ridiculously wide for these little dudes.

Is this a crazy plan?

taboule · May 3, 2016

I wouldn't plant out yet, they're too little. Pot up now, use the below (toilet paper roll) cut in half, or simile, or get creative. All you need it for is ~3 weeks.
a87a8acc0f21d86acf31b5258e9fcb04.jpg

Cole_Robbie · May 3, 2016

If you just re-pot them, you can cram all that extra stem down into the new container and bury it.

loulac · May 4, 2016

Fighting legginess in seedlings can be tricky, finding a delicate balance between light, heat and water comes with experience. I suggest you have a look at Craig LeHoulier 'nctomatoman" here : http://www.craiglehoullier.com/resources/
The legginess has been carefully monitored to make transplanting fast and easy, I wouldn't advise anyone to go further...

Starlight · May 4, 2016

Boy that is some legginess. Usually you get that kind of legginess from not enough light. When your seedlings sprout, keep your lights just maybe like a half to 3/4" in above them. The lights won't burn them. Then as they reach the lights, just raise up tiny bit at a time.

If you don't have enough containers to plant individually down deep, you might get a plastic tub, one that maybe 4 " deep. We call them under the bed plastic bins. Cut a bunch of holes in bottom and sides for drainage, fill with some soil, then plant you seedlings long ways leaving just a little bit of the tops showing and cover with more soil. You want just little foliage showing and put out in some sun.

I wouldn't plant them long ways deep either. That might hold them til you can get outside. Only thing I don't know and more experienced growers might know if with them being that little and if stem buried will they produce new little feeder hairy roots.

There some Tv folks here that know how to tell you do it real well.

May 3, 2016	#1
dforrest Tomatovillian™ Join Date: May 2015 Location: Basque Country of Spain (green, wet) Posts: 8	When to fertilize seedlings? And legginess issues I made a bit of a late start on my seedlings. This is my first year growing my own. So now, May 3, I've got seedlings mostly with their first true leaves, some are starting on the second set. Official time to plant out in my area is May 15th. My seedlings have come out very leggy, especially the tomatillos! One of them is so long it's fallen over and is lying down the length of the modules and is now reorienting itself to grow upward -- don't know what kind of a plant that will grow into, but suppose the bent part will get buried anyway once I plant out. After poking around the forums a bit, I found the cold treatment method and popped the tray out of my heated, lighted germinator and stuck them on a table outside on a south-facing balcony but which gets little to no direct sunlight. It's 10°C/50°F now, forecast high today of 14°C/57°F and low tonight of 7°C/45°F. So maybe a bit colder than ideal, but OK I think. Hope they are not too shocked by the transition from their 25°C/77°F and bright light in the germinator. Due to space issues, there are some peppers in a few modules in the tray, I'm sure this is not ideal for them but they'll have to suck it up and be tough I suppose. I hope they don't stop growing, because I'm verrrry late with them. Another issue I've noticed is that the green color of the leaves is getting lighter and yellower and I'm beginning to think they need fertilizing. And it struck me that I have no idea at all whether, when, or how much to fertilize seedlings. I have a nice organic 10-9-7 with kelp and amino acids that's supposed to promote the growth phase of the plants... Should I just serve it up at regular strength for any old plant? More diluted? Concentrated? Not at all? Something else? I will undoubtedly mix in some Effective Microorganisms (from the local licensee of SDC). I am trying to keep the soil just moist and honestly have only top sprayed once since planting the seeds. Since they've been under saran wrap and then in the germinator, the soil has stayed moist, even on top, and is just now seeming like it needs a watering. Any advice much appreciated.

May 3, 2016	#3
clkeiper Tomatovillian™ Join Date: Nov 2011 Location: ohio Posts: 4,350	Leggines is due to lack of light and heat. cooler weather will make them stockier. also "brush" your hand gently over them once a day to stimulate wind or set a fan to gently blow over them. I use full strength fertilizer not everyone does, but I haven't found it to hurt them. too high of a concentration will, but that is if you don't dilute it properly. it won't hurt the tomatoes to wilt down either. I let mine sit in a perpetual state of wilt right now. It isn't time to get them in the garden and they are already 10" tall. getting beautiful, but they need to wait. I also am letting them stay cooler. You may not want to retard their growth since they aren't very big yet, but getting them to be stockier will be better for them to put in the garden. __________________ carolyn k

May 3, 2016	#6
dforrest Tomatovillian™ Join Date: May 2015 Location: Basque Country of Spain (green, wet) Posts: 8	And what to do with fallen giants? And one additional question while I'm at it... If you notice in the photos, in the two outside columns especially, there are now several seedlings that have gotten so tall, leggy and topheavy that they have lain down and are pretending to be groundcover The two tomatillos that have "fallen" still just have their cotyledon leaves, and four or five others that are more developed but in the same situation. What should I do?

May 3, 2016	#2
Bulldog Tomatovillian™ Join Date: Aug 2015 Location: Georgia Posts: 126	use half strength fertilizer in your water, but yes they will need water. I was watering my seedlings every 2-3 days but it is warmer here. They will also need some light, and transitioning them out slowly is easier on them. How many weeks old are your plants and how tall are the tomatoes? How many seedlings to what size pot? Can you post a picture

May 3, 2016	#4
drew51 Tomatovillian™ Join Date: Dec 2013 Location: Sterling Heights, MI Zone 6a/5b Posts: 1,302	They like it when lows only go down to 50F, so you could probably plant out. But they need 2 weeks to get used to being outside and slowly, very slowly expose them to light. Yes bury the stems. I had room issues this year bigtime because I rooted about 25 fig cuttings. My plants are now used to outside, and night temps are at 40F. Kinda too cold, but they will not die, just be a little set back. They turn a little yellow. Still, they will grow to be fine plants. I had no choice but to boot them outside!

May 3, 2016	#8
taboule Tomatovillian™ Join Date: Jul 2013 Location: MA Posts: 903	Assuming you want to keep the very leggy ones (instead of terminating them) bring the lights very low and close to them and transplant at the next occasion -burying the stems. Make sure you dont over water once you transplant into a bigger pot and use a light mix to avoid drowning the plant or damp off.

May 3, 2016	#12
Cole_Robbie Tomatovillian™ Join Date: Jun 2012 Location: Illinois, zone 6 Posts: 8,407	If you just re-pot them, you can cram all that extra stem down into the new container and bury it.

May 4, 2016	#13
loulac Tomatovillian™ Join Date: Feb 2013 Location: France Posts: 554	Fighting legginess in seedlings can be tricky, finding a delicate balance between light, heat and water comes with experience. I suggest you have a look at Craig LeHoulier 'nctomatoman" here : http://www.craiglehoullier.com/resources/ The legginess has been carefully monitored to make transplanting fast and easy, I wouldn't advise anyone to go further...

May 4, 2016	#14
Starlight Tomatovillian™ Join Date: Jan 2015 Location: AL Posts: 1,993	Boy that is some legginess. Usually you get that kind of legginess from not enough light. When your seedlings sprout, keep your lights just maybe like a half to 3/4" in above them. The lights won't burn them. Then as they reach the lights, just raise up tiny bit at a time. If you don't have enough containers to plant individually down deep, you might get a plastic tub, one that maybe 4 " deep. We call them under the bed plastic bins. Cut a bunch of holes in bottom and sides for drainage, fill with some soil, then plant you seedlings long ways leaving just a little bit of the tops showing and cover with more soil. You want just little foliage showing and put out in some sun. I wouldn't plant them long ways deep either. That might hold them til you can get outside. Only thing I don't know and more experienced growers might know if with them being that little and if stem buried will they produce new little feeder hairy roots. There some Tv folks here that know how to tell you do it real well.