Cosmos in bud - at last!

HotwaxHotwax Posts: 7
Has anyone else had problems with their cosmos not flowering this year? I grew them as usual from seed (sonata mixed) in April, one flowered profusely from July, but all the others grew taller and taller without the sign of a bud even. Now they are about 5 feet tall and are finally budding up! The soil is the same as usual, not overly rich, so why is there such lush green growth but no flowers? I have seen similar rampant flowerless monsters in gardens nearby. So is it the weather? Or the seed? 


  • B3B3 Posts: 11,384
    Rich soil can do it too.
    In London. Keen but lazy.
  • Pete.8Pete.8 Billericay, EssexPosts: 5,008
    I agree, very likely the soil is too rich.
    Mine get to about 6ft tall with masses of foliage - I get masses of flowers too, but winds usually snap the stems - they carry on flowering regardless.
    This year I grew the dwarf varieties and they stayed at about 3ft.
    Every year I get several self-sown plants - they are just coming into flower now at about 4ft
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • PurplerainPurplerain Posts: 1,018
    I had this problem with the white cosmos purity. It grew like a Christmas tree so I don't grow that any longer. I have no trouble with Cranberry and some of the dwarf ones. I tend to start them off in late February to have them ready to plant out at the end of May. 
    SW Scotland
  • HotwaxHotwax Posts: 7
    Hmm. Thanks for that. I wonder if I left them in their modules longer before planting out, so they became a bit stressed, would that push them into flowering earlier?
  • Pete.8Pete.8 Billericay, EssexPosts: 5,008
    I did leave mine (cosmos Purity/Daydream/Pinkie) in modules too long (they were about 2ft high and looked quite poorly) and they started to flower in the modules.
    When I planted them out they still rapidly grew to 6ft as usual...
    That's why this year I grew Dwarf Sonata
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • B3B3 Posts: 11,384
    I don't plant mine out until there's a really good root system in the pot.
    I check after the roots start poking out of the bottom of a small pot. Then I pot them up from small pots to the ones about 4"  high ( don't know what that is in litres) and then plant them in the ground when that one has plenty of roots in it. By that time, the spring flowers are out of the way and the soil has warmed up a bit.
    In London. Keen but lazy.
  • BrexiteerBrexiteer Birmingham Posts: 955
    Mine were done a couple of weeks back now 
  • HexagonHexagon Posts: 1,021
    I had a fair few flowers on my cosmos but it reached nowhere near the heights you're mentioning here! It stayed around 2ft tall.
  • FairygirlFairygirl west central ScotlandPosts: 27,969
    It might be down to timing @Hexagon. You could maybe try sowing some at different times, and see if that makes any difference once you plant them out.  :)
    It's a place where beautiful isn't enough of a word....

  • HexagonHexagon Posts: 1,021
    You might be right. I didn't sow from seed, bought a 1L pot from a nursery and put straight in the ground. Maybe that was in May but maybe June, I can't remember.
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