Cosmos seedling is flowering

matt_fender

Hi all,
I have about 30 Cosmos of different types coming up well under glass. I pinched the tops a few weeks ago and most are starting to branch as they should. I just noticed today that one of the seedlings has sent up two flower buds already, and is only six inches. I probably started these seedlings too early, and they may well be getting quite cold at night.
Any thoughts as to what to do? I wasn't planning to put them out until end of April (we had a frost on 1 May last year on the South coast). Should I pinch out the flowering stems or let it get on with it?

Lyn

Pick the buds off,   There’s still time to sow more, this time of the year they will be up in 2 or 3 days. 

matt_fender

Thanks Lyn. So you think these ones might be compromised, as in not grow to their full potential? The budding ones are Sonata dwarf, if that makes a difference. I've only grown Cosmos once before (last year) and my memory was that they put on all of their vegetative growth, which was a lot, before budding. My fear is that these ones will stick at 6" and I think even this variety isn't supposed to be that dwarf!

Lyn

They will grow, but you need to take the early flowers off so they build a good rootstock. Keep potting them on and picking out the tips, top and side shoots, but you can’t plant them out until May so you’ll need somewhere to keep them.  At the End of April you can start hardening them off, put outside all day and under cover at night, if the weathers good you may be able to plant them out 1st to 2nd week in May. 
Monty Don sows his at the start of June, that gives him flowers right through to autumn.

matt_fender

Thanks again Lyn, I'll keep picking the flower buds off and sow a few more as well. I got a little over excited a month ago and planted too early - must have been that spell of nice weather we had!

JPea\'s

I had the same experience Matt but found putting them in a cold frame after pinching off any buds (I do the same to my geraniums) kept them well and with no detriment to their growth, had am amazing display last summer with some reaching 2m high!

matt_fender

Thanks, that's reassuring!

Lyn

@JPea\'s what grew to 2mts? 

Nollie

Glad you posted on this Matt, I was wondering the same about my little geum plants which are already flowering. They have only been potted on from 9cm pots to 2L pots for a few weeks, so can’t have developed a good root system yet.  I think I should remove the flowering stems. Would you agree @Lyn? 

Lyn

I do Nollie, they need to make a good root system, then when they’re planted out they’re away. 

Nollie

Cheers Lyn, on my way to do it now!