Pub flowers

I have passed this pub several times in the last few weeks, but today was the first time I have been able to stop and blip it. How do they get such an amazing display? I am not keen on the orange and purple combination (see extra) but the whole effect is very impressive.
I was driving out for my regular lunch date with old colleagues. Our host this time doesn't cook so she takes us to a pub near to her home. It has an excellent menu, I must take Normous there some time.