Why are my plants growing so slowly

[ssummer]

Not sure what I could be doing wrong here. All my plants are getting around 300par of light for 12 hours a day. I water from the bottom every 3-4 days. The first photo, the seedlings are about 2 weeks old. They have looked the same since day 5 when they all sprouted. The bottom/second photo these seedlings are 6 weeks old and as you can see only two of them are about 1-2inches tall. What could I be doing wrong here…

 

[adamziegler]

Slow compared to what?

Can I ask what USDA zone you live in?

 

[deluxestogie]

It's not unusual for tiny seedlings to appear to stall for a couple of weeks, then begin to grow dramatically.

Bob

 

[ssummer]

Slow compared to what?

Can I ask what USDA zone you live in?

Philadelphia, so I assume 7b? And as far as my research, if don’t properly indoors within two months they should be nearly 6-8inches tall? Also at what point do I transfer them to solo cups indoors.

 

[ssummer]

It's not unusual for tiny seedlings to appear to stall for a couple of weeks, then begin to grow dramatically.

Bob

Thanks Bob, as I said though the top picture we sowed 1.5 months ago, and my biggest plant is only about 2inches tall, should they not be close to 6inches tall at this point?

 

[deluxestogie]

Some of my seedlings that were started at the beginning of March are still about the size of yours. Alive is good. Be patient.

Bob

 

[MadFarmer]

You're doing it right leaving lots of pics here with timestamps. This way, next year, when you wonder what you've done wrong you can look back at this year's blog and realize you're more or less on schedule. At least this is how it works for me most seasons.

 

[Knucklehead]

Thanks Bob, as I said though the top picture we sowed 1.5 months ago, and my biggest plant is only about 2inches tall, should they not be close to 6inches tall at this point?

The plants are putting their energy toward putting down roots to support the growth spurt you are about to experience. They usually stall again after transplant when given room to spread.

 

[WillQuantrill]

Thanks Bob, as I said though the top picture we sowed 1.5 months ago, and my biggest plant is only about 2inches tall, should they not be close to 6inches tall at this point?

Does your seedling mix have any plant food in it? Are you adding any when you water? As far as 6" in 6 weeks, that has not been my experience. If I up-pot seedlings at 4 weeks at 6 they might be 3" but mine live 8 weeks before transplant and I trim pretty aggressively. At this stage I wouldn't worry about height yet. The important part is growing a thick root ball that will sustain the plant through transplant. I included a picture of some starts I transplanted last year in the same size tray you are using so you can visualize what is happening under the surface.

 

[ssummer]

Does your seedling mix have any plant food in it? Are you adding any when you water? As far as 6" in 6 weeks, that has not been my experience. If I up-pot seedlings at 4 weeks at 6 they might be 3" but mine live 8 weeks before transplant and I trim pretty aggressively. At this stage I wouldn't worry about height yet. The important part is growing a thick root ball that will sustain the plant through transplant. I included a picture of some starts I transplanted last year in the same size tray you are using so you can visualize what is happening under the surface.View attachment 55840

Awesome info. When you say you trim pretty aggressively can you clarify what you mean?

 

[ssummer]

The plants are putting their energy toward putting down roots to support the growth spurt you are about to experience. They usually stall again after transplant when given room to spread.

Awesome thanks, I’m actually leaving about half inch of water at the bottom of tray as well. I know some people like to leave the water and some like to only water from the bottom once a week or so, does it matter that much?

 

[deluxestogie]

If the seedling cell inserts always sit in standing water, then the perched water table will be higher within the soil of the cell. It makes a difference. Tobacco is sub-tropical, so it benefits from ample water—so long as it is intermittent. Tobacco roots need to breathe, and will start to die if completely submerged for more than about 48 hours.

Bob

 

[adamziegler]

7b?

I am 5b and already have them in the garden. I am all for starting things inside to get ahead of climate, but at some point conditions outside are more productive than forcing a process that might have made more sense 8 weeks ago.

You have some expert growers here offering you good advice. I think I am just adding noise at this point.

 

[WillQuantrill]

Awesome info. When you say you trim pretty aggressively can you clarify what you mean?

While still in starter trays I clip about 2/3 of each leaf that is starting to impede light to the other cells. And when the second row of leaves appear I cut the bottom leaves off completely. The bottom row usually ends of getting buried or rest on the ground anyway when I transplant. Your trays may be salvaged if you put a fan close on Low pointed towards the cells and don't add any water for 5 days. I water once every 3 to 4 days. When I add water I watch the level come up about 1/3 of the way up one empty cell and I stop. When the soil is close to dry you would be surprised how quickly it absorbs upwards overnight. Honestly I only water when I can pick up the tray and feel how light it is and that tends to take a few days.

 

[ssummer]

While still in starter trays I clip about 2/3 of each leaf that is starting to impede light to the other cells. And when the second row of leaves appear I cut the bottom leaves off completely. The bottom row usually ends of getting buried or rest on the ground anyway when I transplant. Your trays may be salvaged if you put a fan close on Low pointed towards the cells and don't add any water for 5 days. I water once every 3 to 4 days. When I add water I watch the level come up about 1/3 of the way up one empty cell and I stop. When the soil is close to dry you would be surprised how quickly it absorbs upwards overnight. Honestly I only water when I can pick up the tray and feel how light it is and that tends to take a few days.

Gotcha, so you would cut off the leaf I’m pointing to on the bottom? Also it’s been nearly 3 weeks since these seeds have sprouted snd
Have not grown in the slightest, I water twice a week when they get decently dry, once the trays have soaked up the water I empty the remaining water still sitting in the trays. Also I have just turned up the lighting from 350ppfd to 600ppfd to see if that would make a difference