But they don’t last long. The huge clusters of blooms soon brown and fade. They are great at the right time of the year, but then they are just big green bushes and they need underplanting to make them look more interesting. Here there are wild buttercups and ferns which were just growing below the rhododendrons. Mostly they shade out other plants and in some places they are cut back and removed because they are not native to the UK and they can spread and can be invasive. The shade they cast stops native saplings growing.