Tobacco Seedlings Falling Over

[shamorunner]

Ayo o7,

My seedlings are almost 2 weeks old currently, and I haven't watered them in a few days. I checked on them today and about a dozen of the 350 have fallen over. I don't know if they had bad genetics or the gnats did something to them. I've also only been watering them with a spray bottle gently when their soil dries out. If anyone knows what this is, or what to do about it, please let me know

 

[deluxestogie]

They are tall, and probably do not get enough direct light. Also, I would suggest watering them only from the bottom, after the seeds germinate. You can usually just gently pinch up the soil around the leggy stalk, but your soil appears to be quite coarse.

Bob

 

[Danny M]

Definitely water from the bottom, and you might not have had them in the soil deep enough. It’s easy enough to correct.

 

[Danny M]

Here’s a tip when planting seeds, always make sure the point is down Cucumbers though can be really tricky.

 

[Ginsinjones]

Definitely water from the bottom, and you might not have had them in the soil deep enough. It’s easy enough to correct.

It's my understanding your not supposed to bury tobacco seeds in the soil

 

[Danny M]

It's my understanding your not supposed to bury tobacco seeds in the soil

No, they shouldn’t be buried but I discovered something this year after using those Sterilite containers to germinate seeds. If the soil gets a fissure in it, and seeds go in there, they’ll sprout and oftentimes they’ll be the first to sprout. When tobacco farmers use pelleted seed, it doesn’t lay right on top it goes in a dimple. It’s hard to achieve with Uncoated seed however. So the lesson here is that if they are below level a little it won’t hurt, it seems that little bit of shade, assuming you’re using sunlight helps them. Those I had sitting on top where I could see them were some of the latest to germinate.

 

[deluxestogie]

I currently germinate all my seed on the soil surface. In the past, however, I experimented with a method that @BigBonner tried. Seed was mixed thoroughly with germination soil in a quart mason jar, and the lid put on. The jar was kept warm, until a few bright white radicles were visible through the glass of the side. All the soil was then dumped onto a tray, where all the germinated seeds stood out like Christmas tree lights. They were then individually placed into a dimple within a cell in a 1020 tray.

So they will germinate even when well buried, and those very few varieties that are photosensitive only require a momentary flash of light to get going.

My conclusion is that tobacco seed will germinate at any depth, but the tiny thing (compared to, say, a lima bean seed) does not have much spare energy to go without light and photosynthesis for very long.

Bob

 

[billy]

if you look up photos of damping off allot of them are like that, where a portion of the stem gets skinny and then falls over. cant say if thats what is is or not though. ideally youd want enough light that they dont get taller than wide. fluffier finer soil, like something peat based. temp 75-80f. and let the very surface start to dry sometimes when its safe to do as in the root extends down far enough. as far as sterile soil or not, im not sure that helps. ive had more problems with stuff colonizing sterile soil than when i use mix of 50% compost thats been sitting outside for years. maybe because sterile soil is like a petri dish free to conquer for the first bacteria or fungus that finds it.

 

[Oldfella]

Ayo o7,

My seedlings are almost 2 weeks old currently, and I haven't watered them in a few days. I checked on them today and about a dozen of the 350 have fallen over. I don't know if they had bad genetics or the gnats did something to them. I've also only been watering them with a spray bottle gently when their soil dries out. If anyone knows what this is, or what to do about it, please let me know

I'd agree with Bob and most of the other replies. Your soil looks far too coarse to raise the tiny seeds in. I think the roots are looking for soil to hang on to and the leaves are looking for light, so they fall over. I would suggest, carefully spread some fine seed raising mix around the plants and pinch them into an upright position, once they are standing up you can firm them. Always water from the bottom. I think the plants can sense the water and will send the roots to it.
Good luck with them I'm sure you will have enough survivors to get a grow happening.
Oldfella

 

[skychaser]

So they will germinate even when well buried, and those very few varieties that are photosensitive only require a momentary flash of light to get going.
My conclusion is that tobacco seed will germinate at any depth,
Bob

I disagree on both points. They will not grow if planted to deeply. They may germinate but they will never make it to the surface. Tobacco seed should be sprinkled on the surface with a tiny pinch of soil over it at the most. The dimple needed for pelleted seed is only about twice the coated seeds diameter. Just enough to cover the pellet and keep it moist so the clay coating will dissolve. My experience with pelleted seed is that it takes at least 2-3 times longer to germinate.

And it definitely takes more than "a momentary flash of light" to break photo dormancy in any seed. There are many different enzymes that coat seeds to prevent them from sprouting prematurely in a false spring scenario during a fall or winter warm spell. Some enzymes break down with time and exposure to air and some break down when exposed to light. Freshly harvested tobacco seed will always germ test lower than seed that has sat for 2-3 months. I always try to wait to send my seed in for lab testing until at least January. (I have had over 40 lab tested in this past year) Testing labs always use light when germ testing. Fortunately, in my experience I have found that 99% of tobacco seed is not photo dormant. I have grown over 300 strains from 7 different nicotiana families and have only found 3 strains that were photo dormant. Florescent lights didn't do it. It took several days of full sunlight in the greenhouse to break the dormancy and get them to sprout.

@shamorunner I enlarged your photo and looked at the stem at the soil line. Your problem is dampening off. You are keeping the surface too wet. After the first 2-3 days of the sprouts appearing you should stop misting them and water from the bottom up. And only do it when the surface starts to appear a little dry. A good starter soil mix will wick the water up to the surface from the bottom in about 1/2 hour. Letting the surface dry a little will stop them from dampening off and encourage the roots to grow downward. Never let them stand in water for a long period. No offense intended here, but that is a horrible looking starter mix. It is way to chunky and course. Some seed will fall down the cracks to deep to grow. And it will not disperse the water evenly throughout the soil. It may not wick water up from below very well either. I use nothing but BX Pro Mix now days. And I screen it through 1/4" hardware cloth to remove anything larger. I buy BX in 60 lb bales from a large AG supplier here. But depending on where you live, finding a good starter can be difficult. Sometimes you have to make due with the best you can find locally. Walmart sells Pro Mix in a retail version of the BX. It works well but has more chunks than the BX and needs screening to remove some chunky bits of wood that haven't fully broken down. Chunks will block the drain holes in small pots and you get a lot of dampening off or wind up drowning the seedlings because the water can't drain away. What ever you end up using, I always advise everyone to screen it. Also, your plants do look like they are stretching for the light and getting "leggy". Move the lights closer.

You are still doing better than I did my first year. I was advised to use a good starter mix but didn't listen. I tried using garden soil. Which was a freekin' disaster! lol Live and learn.

Sky

 

[deluxestogie]

Sorry, I should have provided a reference with regard to tobacco photodormancy.

"Tobacco photodormancy: Light is required for at least two aspects of tobacco seed germination (review: Leubner-Metzger 2003). First, in photodormant tobacco seeds germination in darkness is blocked at a step before testa rupture and neither neither testa nor endosperm rupture occur even after several weeks of dark-imbibition. Brief treatment of imbibed photodormant seeds with red light activates the phytochrome signal transduction pathway resulting in the release of photodormancy and the promotion of germination."

The Seed Biology Place - Seed Dormancy

www.seedbiology.de

Germination rates and non-photodormancy studies are all over the place, with results varying from location to location, seed year to seed year, brands of pelletized seed, and especially harvest conditions and storage conditions of the seed. I have all the references for those studies, but they are not really worth the time to read.

Bob