Starting seeds in unheated conservatory

I’ve bought a few packets of seeds and have never grown from seed before. Two packets can be directly sown but the other two mention a greenhouse. Can I use my conservatory for this? It is south facing and unheated. It has no blinds up so is there a possibility of the sun being too strong? Will I need any particular equipment or a way to measure and control humidity? I have seen seed trays with little plastic lids before which seemed to work like tiny greenhouses - will I need this sort of thing if it is inside the conservatory?



  • ObelixxObelixx Vendée, Western FrancePosts: 15,962
    Seeds need warmth and moisture to germinate and when they do, the seedlings need plenty of light to grow strong and sturdy.    Your seed packets should indicate sowing times and depths.

    If you tell us what you have, we can give your more specific advice about when to sow, how to sow, whether to cover or not and so on......
    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • Hostafan1Hostafan1 Posts: 20,219
    be aware of temperature fluctuations. When it's sunny , it'll probably become very hot , very quickly, but during cold snaps, it'll probably get very cold at night.
  • SplandySplandy Posts: 125
    I have a packet of foxgloves and one of Cosmos which are the ones I was going to sow directly into the border. They say to sow into a prepared seed bed but will it be ok to rake the soil over and scatter them into the border? 

    The two which say to sow indoors are didiscus blue lace and ammi majus. The didiscus seeds say to cover with glass, polythene or propagator lid and keep at 15-20 degrees. Then remove cover when seedlings appear, transplant when large enough and grow on at 13-15 degrees, and to gradually introduce outdoors in late May. I don’t know how to ensure the correct temperatures. Ammi majus does have an outdoor sowing instruction but I can’t tell whether it’ll flower the following year or during the current year. The packet says outdoor sowing needs to be done April to June or August to October. It then says it they will flower from June to September but late sowings will flower earlier the following year. Does that mean that if I sow outdoors in April to June then I will get flowers this year from June to September?
  • ObelixxObelixx Vendée, Western FrancePosts: 15,962
    You need to wait till March for decent light levels.  This will give you time to investigate simple heated propagators which allow you to control the heat of the seed trays.   You don't need a huge or fancy one as long as it has thermostat control so you can determine the temperature.

    Foxgloves don't need heat and can be sown in ordinary trays.  Better still is to buy module trays and sow just a teeny amount of seed in each one.  Much easier for the later process of pricking out and growing on.  I wouldn't sow Cosmos direct either.  Go for modules and prick out and pot on to get strong sturdy plants ready to go out in mid May. 

    Ammi will flower this year if sown early and grown on before planting out.    Later sowings need to over-winter as they don't have time to grow big enough to flower if sown in late summer.
    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • SplandySplandy Posts: 125
    Thanks for the advice. Why is it better to sow cosmos and foxgloves indoors? I didn't want to try to do too many seeds indoors for my first time and end up not having time to deal with them properly. 

    When you say that those two don't need heat, does it mean that the conservatory is the wrong place to grow them? Will direct sunlight coming through be too strong so should I put them somewhere other than on the windowsills? 
  • ObelixxObelixx Vendée, Western FrancePosts: 15,962
    If you sow them direct outdoors they can be eaten by birds or disturbed so they end up too shallow or too deep.  Once they germinate they can be eaten by pests or accidentally weeded or be frozen by a late frost or shriveled by a hot or dry spell. 

    Seed trays, modules and propagators help you control the initial environment for better germination and early growth.    It is also much easier to thin and pot on seedlings in modules or seed trays.   An alternative would be to have a dedicated seed bed in your garden where you have worked the soil to a fine tilth and can provide cloches to protect against heavy rain or cold weather and also water more easily in hot spells.

    If you do still want to sow directly outdoors, make sure you prepare the soil well and sow your seeds in straight rows, even in a curved space, so you can recognise the wanted seedlings and weed out weedlings.
    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • SplandySplandy Posts: 125
    You’re right, that does sound like a better idea. And do you think the conservatory will be an ok place to do this? 
  • ObelixxObelixx Vendée, Western FrancePosts: 15,962
    If it has plenty of light and you can provide a constant temperature by means of a heated propagator for the germination of the ones that need heat.   

    have a read of this - 
    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • Jacqueline29Jacqueline29 Posts: 316

    Hi Splandy, I am just about to start seed sowing again this year. I to have an outdoor greenhouse but it is not heated, and the light is not good to start seed growing. However, I always start my seeds off by sowing them in little containers with lids. I place them inside the house on the windowsill. And also near a radiator. They get the light from the window, and when the seeds start to sprout I take the lids off the containers. I find it works out fine for me. Good seed planting. 
  • SplandySplandy Posts: 125
    Thanks Jacqueline. Are they south facing windows? I’m having difficulty working out what is the right level of light. I don’t have any radiators under windows so that might be the coolest area of the room. Do you have heat pads underneath the trays or is that just plastic to keep the windowsill clean?

    Does anybody know how important it is to get those specific temperatures mentioned on the back of one of my seed packets? The heated propogators whichout variable temperature control are much more affordable but would be a waste if variable control is absolutely necessary.
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