By Tonyandgay
Gloucestershire,
United Kingdom 
I have two buddleias which I bought as small plants last year. One hasn't grown very much, but has loads of flowers. The other has grown an enormous amount, but has no sign of any flowers at all! Although they are in different borders they are in the same type of soil and have received the same treatment. Can anybody tell me why the big one isn't flowering and if there is anything I can do about it? Many thanks.
14 Jul, 2010
Answers
Thanks for responding. They are both buddleia davidii - one (which is flowering) is Empire Blue and the one with no flowers is Royal Red. Surely the colour shouldn't make any difference!
14 Jul, 2010
No, it shouldn't make a difference, the colour I mean, Donna I suspect asked because you might have had a different form of Buddleia - there are 2 others which flower at different times.
Clearly there's something different about their situations which you are not aware of - both these should be the same size, so I'd hazard a guess that the smaller one has less access to nutrients, nitrogen particularly, and the other one is in richer soil, or perhaps a shadier spot than the other, and thus able to access more nitrogen and grow larger. Patience I suspect - it might just flower a bit later, end of the month or early August.
14 Jul, 2010
Are they the same variety too?
14 Jul, 2010