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Will Cosmos survive frost?

Shane15Shane15 Posts: 4

I've had a large amount of Cosmos plug plants delivered to me, however, i do not have any greenhouse to put them in or enough room indoors to accommodate them. Will they survive if i plant the plug plants outside at the start of April and cover them with those frost protection fleece's at night?

I am currently residing in West Yorkshire



  • PerkiPerki Posts: 2,327
    Sorry they will stand no chance of surviving outside at this time of year. plug plants need growing on into large pots then they are planted out around late May for you. Not only will frost kill them ( forecast next week ) the slug will soon see them off as well.  
  • AnniDAnniD Posts: 11,158
     @Shane15   I agree, even with the fleece they would suffer. Do you have a friend or relative nearby with a greenhouse or spare windowsills who could help out ?
  • B3B3 Posts: 24,425
    If all else fails, buy some seeds. You can put them in trays outside very soon. They might be a little late but they'll flower through to the first hardish frost.
    In London. Keen but lazy.
  • TopbirdTopbird Posts: 7,704
    I certainly wouldn't plant them out for the above reasons.

    How many is 'a large number'? How many do you actually need? - some varieties of cosmos grow as large as a small shrub.

    It was too early to buy these plug plants without being able to protect them (but you know that now😉😜) so you have to accept there may be some losses. However, I'd suggest:

    Buy a couple of pot trays - they're moulded plastic trays containing around 15 or 20  3" or 4" pots - and they'll last for a good few years. The trays enable you to carry 15 / 20 pots at a time. 

    Pot the plants up and find or make a very sheltered spot in your garden - preferably near the back door. The trays can then go outside during the day when the temp is about 10C or above and they're easy to carry inside for overnight / cold day protection.
    Heaven is ... sitting in the garden with a G&T and a cat while watching the sun go down
  • LynLyn Posts: 21,332
    The main downside to either sowing or buying too early is that you will need to keep potting on until mid May, by them you’ve got to house several 4 or 5 flower pots. 
    Gardening on the wild, windy west side of Dartmoor. 

  • Shane15Shane15 Posts: 4
    edited May 2019
    Hi all. Sorry for late reply-been on hols. They managed to survive the frosts. But i won't be making the same error again! I gave 15 to my friend (ordered 60) to pot up and keep in a greenhouse) On a side note, i wont be ordering from J Parkers again, the plants have all come up stunted, including the greenhouse potted ones. I've also ordered some other plants from them with poor results). thanks for the replies
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