London (change)
Today 9°C / 7°C
Tomorrow 9°C / 4°C
11 messages
18/06/2013 at 00:02

Hi everyone

Not been on for a few weeks, maybe even months. I have my delphiniums that are in flower just now but....if I cut them back will they give a second show or do I leave them to seed??? Also, will they come true to the colour they are when they flower??? Thanks.

18/06/2013 at 00:24

It can be hit and miss as to whether you get a second flush - depends on the weather.  Some varieties will self seed, others (F1s) are often sterile.  I've grown seeds from some of mine (parents were all blue) and got a mixture of colours, but many were quite bland (eg dirty whites and some with sparse flowers.)  One thing I've learnt from experience is to cut them down right to the ground at the end of the year.  I left some until the next spring once (I usually leave most of my plants uncut to provide winter cover for wildlife) but found that the next year the flowers had all been eaten when they were small by caterpillars of the delphinium moth.  They overwinter inside the hollow stems..

18/06/2013 at 01:50

Delphinium moth? I havent come across that. Can I prevent that Bob?

18/06/2013 at 07:07

Hi there OW - welcome back !

I once quizzed the Blackmore and Langdon people at Hampton Court - he said always cut the flower spikes on delphiniums back as that makes them concentrate on becoming stronger plants for next year, rather than putting all their energy into setting seed.

18/06/2013 at 07:15

Yes, I don't leave delphiniums to set seed - I find they make stronger plants for next year if I don't, and I usually get a few more blooms from sideshoots if the weather is kind. 

18/06/2013 at 08:43

I cut delphiniums back as soon as flower,spike is going over.  I cut back entirely to,the ground or to lateral/ secondary flowers lower down on that stem.  The sooner this is done the more,likely it is that they will flower,again in late summer.  I agree with Bob.....I came to exactly the same conclusion, viz., to cut back everything to the ground in the autumn, for the same reasons.  (I find that cutting flowered stems on all sorts of plants before they totally go over often encourages earlier repeat flowering)

18/06/2013 at 23:48

Ahhh. brilliant folks. Will get that done tomorrow  Thanks for the welcome back chiky.xx

19/06/2013 at 00:09

Yes...welcome back Oakley

19/06/2013 at 12:17

Welcome back nice to here from you again - me not managed to grow delphinium that flower yet as only started to grow them this year - they are only small seedling

27/06/2013 at 13:42

Thanks folks  Lucy, they will flower next year hun. Get the seeds in now and they will flower next year. I have done my blue/purple mix but have just bought some lovely tall white ones for the moon garden so off to sow them this afternoon (and play with my new purple trug)

09/09/2014 at 21:50


I live in the Pacific Northwest of the US, so it's weather kind of like Britain.  I've heard that putting a plastic pot over the cut down delphinium can help prevent rotting in our rainy climate.  Has anyone done that and had success in wintering over?

email image
11 messages