Topic: Lettuce - Sowing/Germination

[garyp]

Warning! new allotment holder in action again!!
Looking for some help with Lettuces. I thought that I would start sowing some lettuces in modules so that I would have some nice healthy plants to put out! But firstly the germination seems to be pretty erratic. The ones I have got to germinate have grown as very weak. A light watering causes them to keel over in a heap. They have been germinated on a windowsill and then transefered outside to one of those plastic mini-greenhouses. Varieties include Webbs Wonderful, Salad Bowl, Marvel of 4 seasons. Just wondering why germination is slow and erratic. I think I will have to ditch this sowing as they look pretty weak and helpless. Any help please!

[rdak]

I sowed some lettuce inside in modules too on a windowsill. Variety was 'Tom Thumb'. Germination was erratic too- I think only 20% germinated- and strangely only those around the edge of the module tray.
If they are only keeling over when watering, perhaps try watering with a spray? If they are keeling over anyway, perhaps they didn't get enough light. Are they all leaning over in one direction to try and get to the light? I have to turn my seed trays around each day to compensate for this. If they are just generally keeled over, then perhaps it's best to get rid of them and start again.

[john_miller]

  Lettuce need light to germinate. Did you bury the seeds? Try surface sowing the seed late in the afternoon to allow the seeds to get the required light but reducing the chance of them drying out. Once the light requirement is met, just a few hours, they can then be covered. Lettuce are also subject to high temperature dormancy. If it is too hot, 15C approximately, when they are sown they will not germinate. A windowsill in bright sun, even in the U.K., will achieve this so evening sowing will also overcome this. Older varieties such as Tom Thumb are especially prone to this.

[cleo]

Although John is technically correct my experience is that they are a bit more tolerant to temperature and being covered than that-but it`s worth trying.

And lettuce seedlings do tend to look a bit `sad` when young but soon pick up.

Stephan.

[tim]

Surely, the compost should be moist enough to see them through to seedling stage, without further watering?

And while on the subject, why do the 'old wives' always say 'cover with brown paper'?

And the light - is that why, if you spill seeds at the end of a row, every one will germinate? S-d's law? = Tim

[Mrs Ava]

Cor, Emma sits with big smug grin, lettuce grow like weeds for me!  No problems, I would say, near on 100% germination  ;D  not that I like to brag....MUCH!  hehehe.  Always taught that lettuce like cool conditions to germinate, so I keep them almost chilly.  They do look floppy, but then lettuce are kinda like that aren't they?  Just planted some on the plot under bottle cloches and they look sooooooooper!

[garyp]

And there I was thinking I would get the sympathy vote being my first season as a grower :'(
100% germination Emma, your having a laugh aint yer?!
After giving them a light sprinkling of water there certainly were floppy, well to be precise parallel to the ground! I have ditched those seedlings and started afresh. Yes I did moisten the compost after sowing and the seedlings were about 3cm high with their true leaves coming through. In my short experience of growing in modules, they do tend to dry out quickly and need to be watered reguarly. Here goes with the next lot anyway, though I doubt I will be able to match SuperVeg grower EJ!!!!

[Mrs Ava]

 ;Dhehehehehe.  Super veg grower I am certainly not.  Lettuce is just one of those things that I can do.  Now peas and sweetcorn are another matter!  Both are hit and miss with me.  I fine my lettuce go floppy when I water them gary, spesh if I am a bit heavy handed, but they soon seem to perk up, and are like little strong green leafy....well lettuce now!  ;D

[tim]

Right or wrong, I never water from above. As said, it can flatten weak seedlings; it does not get to the roots and will therefore dry out more quickly; & it may encourage damping off?
Any thoughts on my 'brown paper' yet?? = Tim

[garyp]

Tim - yes that makes sense about giving water from below. I will give that a try.  :)

[jammyd]

Nuts! I covered my lettuce seeds with soil... ah well, back to the drawing board!

j

[DarkSkies]

Nuts! I covered my lettuce seeds with soil... ah well, back to the drawing board!

j

I did the same, but left mine too long in my propegator.  I think they were murcilessly decimated by damping off.  I am trying again now.  Mine didnt mind the covering of soil tho.

[Dunc_n_Tricia]

I tend to find lettuce very forgiving. They germinate quicker if surface sown, but come up eventually somehow if covered with a bit of compost.

garyp, there is no need to chuck out young seedlings which fall over when they are watered. Give them a day or so and most will pick them selves up - hardy little things really.

 :-* Tricia

[Mrs Ava]

I agree, watered my italian mix earlier today, and they all laid flat and I thought...oh oh...but when I went up a short while ago to shut the greenhouse door, they were all upright and looking rather lovely!

[tim]

SO? Lesson? = Tim

[Hugh_Jones]

Just a thought on the brown paper, tim.  As it has a nice shiny side the effect would be very similar to covering with glass - keeping a close environment rather like a modern propagator - while at the same time excluding light.  Quite possibly, in the days of your particular old wives it was not realised that not all seeds need to have light excluded.

[Sparky]

Phew!  Just got in from work to find that my lettuce seedlings had flopped and was panicking I'd killed em all when i watered them this morning!  Now after reading all these i will chill out and leave them be! 8)

Thanks

Sparky

[garyp]

Well, I have done a couple of new sowings. The first was sowing the seeds just below the surface. This has brought a very high germination rate. I also watered from the bottom by putting in a tray of water for a period of time until I could see the surface of the compost getting damp. Then emptying the surplus water out of the tray.
It takes longer than watering on the top but it does give I think a more thorough watering. I think as tim said the water gets to the roots rather than just on the surface.
My second sowing was leaving seeds on the surface and covered the modules with clingfilm.
These are just beginning to germinate so will have to wait and see how they develop. Interesting to see the seed develop on the surface though. There is a little area which develops which has very fine white hairs. I presume this is the root system developing. Which I suppose in some way has the instinct to head into the compost?
So at the moment it is all big smiles  ;D ;D ;D

[john_miller]

  All plants (I think), Gary, exhibit geotropism, a sensitivity to gravity. That is how they know which way is up!
  Something I should probably have mentioned is that what really works well with lettuce is to lightly dust fine vermiculite onto the seeds and soil surface following sowing. Thin enough that you can barely see the seed. This might be the modern brown paper Tim? It also makes the seedlings temporarily invisible to sparrows. They will pull them up expecting a feast, especially if sown in an open greenhouse in the summer.  
 

[garyp]

John, thanks for that. It has been fascinating watching the seed develop over the last couple of days. They have now developed short stems with the seed leaves showing. The fine white hairs have started to bury themselves into the compost. The effect of gravity as you said. Its a high germination rate as well probably 95%.