Leek sprouts don't root

[Vanisle_BC]

This could perhaps be in the onion forum; I think some of my onion seeds have done the same as these leeks. The seeds germinate but instead of putting a root down and a shoot up, the puny sprouts sprawl on the surface. Like dreams in the old song about the Mona Lisa, 'They just lie there, and they die there.'

Any opinions on why this happens - just non vigorous, barely viable seed; or what? I sow them just scattered & patted into the soil, then thinly covered. I don't think they usually need much cover?

[applestar]

I think I’m going to move this thread to our brand-new Onion Forum in a minute.

I think I can guess the reason the onion/leek seedlings do this — onion seedlings grow mostly unbranched roots, and start with a single taproot. Onion seeds don’t grow a pair of seedleaves and then true leaves thereafter — instead, they start with a single loop that emerges from the seed shell/husk, elongates and then literally unfold and stand up twice as tall just about when you might think “trueleaves” would start growing. This is also when they start to grow more roots and more leaves, but for the moment, they only have one or two unbranched/minimally branched smooth roots

So sometimes, as the single leaf tries to extricate from the seed husk and stand up straight, and the angular/pyramidal seed husk is securely situated in the soil ... it manages to do a headstand and pulls out its root(s). Sometimes only a bit and sometimes pulling itself up and out by the root entirely.


Basic rule of thumb is to cover seeds as deep as they are thick. Bare minimum needed when indoors but a little bit more — twice as deep — when outdoors. Seeds should be pressed in to make full/firm contact With surrounding soil(mix). I like using white or light colored sand for surface sow seeds that should be pressed into the surface — just sprinkle to single grain layer of sand for indoor sowing projects — it has to be a bit deeper outdoors to avoid seeds being blown or washed away, but step on them with flat-bottomed shoes or firm with a piece of lumber, brick, etc. Carrots, etc. benefits from board or cardboard cover until germination to prevent drying out.

[imafan26]

I usually start leeks and green onions in pots. It takes a long time to germinate. Soaking seeds in warm water overnight does help. I do surface sow seeds, but I cover them with a light layer of potting mix. To keep the seeds from moving when they are watered, I put a paper towel on top of the soil and water thru the paper towel. I start checking the seeds about 10-14 days later to see if any have sprouted. When they sprout, I carefully remove the paper towel and then it is best to bottom water for 10 minutes and then drain the pots. Once the plants are big enough, I divide the community pot if a lot of seed sprouted and transfer the seedlings to gallon pots. They will pretty much stay in the gallon pots until they die.

[Vanisle_BC]

That's an interesting idea, Applestar, about the 'headstanding' leek/onion sprouts; but it seems some of my sowings do it much more than others. I think that must have something to do with seed batches and soil or watering conditions.

Incidentally these were planted as black seeds, already freed fom the fibrous cover that I call the husk - although you maybe used the word in a different sense.

[imafan26]

Actually, the picture looks more like the seeds were planted very shallowly and the soil was top watered to strongly. If it is in the soil, misting would be better if it could not be bottom watered. The paper towel trick works on the ground too.

[Gary350]

I think I’m going to move this thread to our brand-new Onion Forum in a minute.

I think I can guess the reason the onion/leek seedlings do this — onion seedlings grow mostly unbranched roots, and start with a single taproot. Onion seeds don’t grow a pair of seedleaves and then true leaves thereafter — instead, they start with a single loop that emerges from the seed shell/husk, elongates and then literally unfold and stand up twice as tall just about when you might think “trueleaves” would start growing. This is also when they start to grow more roots and more leaves, but for the moment, they only have one or two unbranched/minimally branched smooth roots

So sometimes, as the single leaf tries to extricate from the seed husk and stand up straight, and the angular/pyramidal seed husk is securely situated in the soil ... it manages to do a headstand and pulls out its root(s). Sometimes only a bit and sometimes pulling itself up and out by the root entirely.


Basic rule of thumb is to cover seeds as deep as they are thick. Bare minimum needed when indoors but a little bit more — twice as deep — when outdoors. Seeds should be pressed in to make full/firm contact With surrounding soil(mix). I like using white or light colored sand for surface sow seeds that should be pressed into the surface — just sprinkle to single grain layer of sand for indoor sowing projects — it has to be a bit deeper outdoors to avoid seeds being blown or washed away, but step on them with flat-bottomed shoes or firm with a piece of lumber, brick, etc. Carrots, etc. benefits from board or cardboard cover until germination to prevent drying out.

I found a YouTube video that shows cutting the loop with scissors promotes the plant to grow a 2nd root and a 2nd ring. Then your plant will have 2 roots & 2 rings. Home gardener can do this to a small crop but commercial growers can't do this to a 1000 acres of onions so they plant extra seeds to make up for plants that don't live.

Here is another good onion video. If I could learn to grow 100 big onions I would not need to grow 500 golf ball size onions.

https://www.youtube.com/watch?v=-4wNpwPQRa8

[imafan26]

When I plant onion seeds, I usually plant them in community pots thickly. When they are planted that way with a paper towel cover until they germinate and bottom watering or misting when they are small, they usually will grow straight up. If the seedlings are not planted thickly then I get more of the onions growing crooked. They use each other to hold themselves up. When they are large enough, like 3-4 inches tall, I divide and transplant them.

I grow mainly green onions and leek so they are always in pots and I grow them in bunches. Even in the pots after I divide them, they don't like to be moved. The tops fall over and they get messy, so I cut the tops so they will grow back straight again.

I have grown bulb onions in the past, but they take up too much space in my garden and they can't be kept for long, so it is cheaper for me to buy it than to grow it.

Green onions and leeks on the other hand are very easy to grow in 1 gallon containers and they are cut and come again. For me, I can get repeated harvests for at least 2 years. A bunch of green onions in the market costs $2.99, so I really feel guilty if I am not growing my own.

[pepperhead212]

I do that all the time - the cut and come again - with scallions, but never thought about doing it with leeks - thanks for the idea!