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Trying to understand the science of germination

LatimerLatimer Posts: 1,068
Hi all,

I popped out today to have a look at the state of some of the seeds I sowed last weekend and left in the cold frame and there was absolutely no movement at all!

So I took to the internet to try to understand why.

If I understand correctly, seeds need heat, not light to germinate. Different seeds have different temperatures at which they can germinate but that the rate of germination will slow down the lower the temperature. I didn't read this, but I assume that fluctuating temperatures also have an effect (day and night).

Therefore (and I'm simplifying here, I know there are other options) I (in my present set up) can either sow seeds indoor in our conservatory or outdoor in the cold frame and the pros and cons to both are:

Indoor: 
Constant warm temperature therefore faster speed of germination but once germinated, light levels are potentially lower leading to leggy plants. Requires hardening off, so a week of lugging everything in and out every day. 

Cold frame: 
Fluctuating and colder temperatures leading to potentially less successful germination and a much slower germination rate. However, plants are grown from "birth" into tougher conditions and are therefore potentially stronger healthier plants. Light levels should be higher though I'm not convinced it's that much brighter in the cold frames than in the conservatory. The cold frames only get marginally more direct sunlight than the conservatory.

Is there anything above I am getting wrong in a major way?

Thanks all!
I’ve no idea what I’m doing. 

Posts

  • B3B3 Posts: 27,505
    Mostly expecting them to germinate so quickly. For example, cosmos in the right conditions, can germinate in a week or so but parsley takes weeks
    In London. Keen but lazy.
  • tui34tui34 Posts: 3,493
    Absolute minimum: 10 days - in a light atmosphere - if sown say mid-end February - in an unheated conservatory for example.

    As @B3 states  - parsley under normal conditions can take up to a month and courgettes or beans - within the week.






    A good hoeing is worth two waterings.

  • fidgetbonesfidgetbones Posts: 17,618
    Some seeds such as field poppy need light to germinate. Hence when land is freshly dug over, they germinate after years of dormancy.  That is why the fields of flanders turned red after WW1.
  • LatimerLatimer Posts: 1,068
    @B3 @tuikowhai34 and @fidgetbones thanks.

    As usual a lack of patience is my downfall!! I suppose it's just difficult to generalise but I'll keep an eye on everything.

    Should I move them indoor if I have the space? Do the pros outweigh the cons?
    I’ve no idea what I’m doing. 
  • tui34tui34 Posts: 3,493
    I would move them indoors as your climate is cooler than mine.  Albeit, we are having quite a cold end of winter/beg. spring.   I sowed peppers 18th February (in the unheated conservatory - I cover a polystyrene box - used for fresh fish - with plastic) and the last of them are just surfacing now.  I thought they had rotted in the compost.              
    I laugh like a drain every year around June after having planted my various carefully nurtured veggie plants , when up have sprouted tomatoes, peppers etc as weeds do,  all around the garden, stronger than ever!
    A good hoeing is worth two waterings.

  • B3B3 Posts: 27,505
    I had loads of self-seeded tomatoes last year. I transplanted some of them. Very nice they were too. I'm hoping some will pop up this year. The trouble is, you don't know whether they're any good  until you taste them. Same with unfamiliar ones bought in a packet, I suppose. 
    In London. Keen but lazy.
  • tui34tui34 Posts: 3,493
    @B3  They usually taste good - like all rogues!!
    A good hoeing is worth two waterings.

  • LatimerLatimer Posts: 1,068
    Thanks @tuikowhai34, I'll do that.


    I’ve no idea what I’m doing. 
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