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How to keep seedlings / plants warm indoors?

hc1994hc1994 Posts: 7
in Plants
Hi everyone, 

I'm growing some cosmos from seed indoors. The house gets cold during the day while I'm out (about 14.5c degrees) and even colder during the night (down to 12.5c), so I used some pricked cling film to cover one of the trays and a propagator lid for the other, and somehow, four days later, they have germinated and are doing very well from what I can tell with my limited knowledge. I should also add that the central heating goes on for 20 mins three times a day at 18c, so maybe this helped the plants to combat against the long periods of cold.

I read that as soon as germination occurs, you're supposed to whip off the lids/covers to avoid too much humidity, so that's what I've done. But can I put the propagator lid and cling film back on overnight to keep things warm during the cold nights, or will this impact the plants?

I've got the trays swaddled in a blanket and some insulation sheeting, with the trays popped on top, but I don't like the idea of leaving the plants open and exposed to the cold at night. I've attached some pics so you can see what I've done. I know it all looks a bit unorthodox, but it's all I had to hand! The tray under the propagator in the pics is some rudbeckia that hasn't come through yet, but you can see how I'm using the insulation sheets to keep the tray warm.

Does anyone have any extra tips I can apply that don't involve electricity? I know I can buy heat pads/lamps, but I have limited space to grow indoors and don't want to have additional bits and bobs and wires everywhere. 

Many thanks for anyone who has any advice or suggestions!

Holly




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Posts

  • philippasmith2philippasmith2 Posts: 3,742
    Once your seeds have germinated they will want light and air.  
    If your house is warm enough for you to survive, then so should your seedlings.
    You could make a bit of a frame and drape fleece over for the night if you are really concerned about the temps dropping.
    From your pics it looks as if your seedlings are already stretching for light and your compost level is too low.
    Without further info ( eg do you have a GH or Cold frame available ) it's a bit difficult to make useful sggestions.

  • hc1994hc1994 Posts: 7
    Hi Philippa, 

    Many thanks for your reply. I didn't realise the compost level was low - is this something I can rectify now? I have a cold frame I can use that is in the garden. 

    Holly 
  • FairygirlFairygirl Posts: 55,117
    To be honest- this is always the problem with sowing early. Much easier to wait until temps are higher. Less fuss - less problem trying to keep seedlings warm, or give them enough light.  :)
    You can't do much now about the soil level. It should be within half an inch of the top of the tray to prevent etiolation - ie reaching for light. 
    If you have more seed, do another batch next month  :)
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • hc1994hc1994 Posts: 7
    Thanks! I have tonnes of seed, so I'll plant again in March and up the soil levels. Many thanks for your input, both. Hopefully next time round I'll fair better :smile:
  • FairygirlFairygirl Posts: 55,117
    It's always good to do a bit of experimenting, and see what works best.  :)
    At least you have plenty of seed. That's a big bonus.
    We often used to get people on the forum saying [when they had a problem]  'oh, I sowed the whole packet of seed'. Not much you can do at that point apart from buying more  ;)
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • hc1994hc1994 Posts: 7
    Yes, exactly! At least now I know for next time :smile:
  • FairygirlFairygirl Posts: 55,117
    Good luck with the next lot, and your current ones might be fine anyway. Cosmos is a plant that benefits from pinching out as it grows, to make it bushier, so all is not lost  :)
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • Nanny BeachNanny Beach Posts: 8,719
    I'm in the cosy SE UK corner,and the only thing I sow before march is tomato and peppers. I don't bother with heat, wrapping, covering. They are all sown in my north facing kitchen window, when they germinate,they go into the conservatory, which will go down to 10c if it's frosty. When they reach about ,6 inches, they will be in a barely frost free green house.
  • philippasmith2philippasmith2 Posts: 3,742
    That's the best way to look at it @hollyrosecarolan. At least you know where to come to ask if you are stuck :)
  • FairygirlFairygirl Posts: 55,117
    As is always the case- it's not the germinating of seed that matters, it's what you do afterwards, especially if they all germinate.
    You need somewhere to keep them when they've been potted on, and before they go outside. That's where the timing, re weather and temps, comes into it, and it also depends on what the plant is too.  :)
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
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