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Cosmos not flowering!

Reb_tReb_t Posts: 47
Hi,
I have grown cosmos from seed, planted them out but not one has flowered! They are really healthy looking plants really big and bushy and loads of foliage, but just no flowers. What am I doing wrong?!

Posts

  • fidgetbonesfidgetbones Posts: 17,618
    Too much nitrogen.  Stop feeding them and they will flower, later than usual, but  probably better and bigger and for longer.
  • Reb_tReb_t Posts: 47
    Ah ok!! Thank you!
    I did give them some feed...well probably quite a bit 😂 
    I'll stop spoiling them, and next year will try again and neglect them a little!!
    Fingers crossed for big flowers then!
  • FireFire Posts: 19,096
    If they are planted into rich soil that has compost/manure they will also build up very healthy, large plants. The advantage is that you will have flowering trees into Oct, when lots of other flowers have gone over. Worth doing it, just for that.
  • JemulaJemula Posts: 196
    In addition to advice given above, Sarah Raven reckons that some of our cosmos seed is grown in Morocco where the growing season is longer but the days are shorter, which makes plants grow very tall and flower later than usual.  Link to notes from her podcast earlier this year about this.
    https://www.sarahraven.com/podcast/show-notes-ep067

  • Reb_tReb_t Posts: 47
    Thanks for your comments. 
    I planted some in pots and some in the boarders, all with a sprinkling of miracle grow granules  😁. The ones in pots are also in a peat free compost and were fed.
    They are getting to the size of trees 🤣
    Hoping there will be some tree size flowers on there now! Haha
  • Reb_tReb_t Posts: 47
    Hi Jemula, 
    Thanks for the link to the podcast, that was really interesting, and exactly what mine are doing! 
    I will listen to more of them 👍😊
  • JemulaJemula Posts: 196
    Hi Reb_t - yes, interesting to hear results from all the trials done at her garden at Perch Hill and Sarah's enthusiasm always comes across.
  • I grew Apricotta this year and it took an age for it to flower and then it lost its steam after a few flowers. Also, they weren't self-supporting unlike the more usual varieties. Did anyone find that theirs were very slow this year? 
  • GardenerSuzeGardenerSuze Posts: 5,692
    edited August 2022
    I have grown C Rubenza, five jumbo seedlings from Sarah Raven. They had germinated well and I actually had ten good plants after gently teasing them apart. They have been in a new border all summer and there has been hundreds of flowers. I have done lots of deadheading but worth the effort. Also grew C Apricot Lemonade as Jumbo plugs from Sarah Raven not worth growing some were more pink than apricot. 
    Still puzzled by the really tall ones they are only just starting to flower sadly don't remember what they are, good addition for autumn.
    I would like to know anyones thoughts on C Click Cranberry? If that is correct. Also are the Orange ones worth growing please.
    I have worked as a Gardener for 24 years. My latest garden is a new build garden on heavy clay.
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