Dodgy weeds in the Netherlands

I drew this plant at Keukenhof in the Netherlands (a short bus ride from Amsterdam), which is a big flower garden that everyone tells you to visit if you're there in April. It was a bit of a disappointment as it was so pristine and organised that it felt like a giant garden centre.

Interesting(?) fact: if you visit Amsterdam in April, when all the tulips are out, thinking that some tulip bulbs (as sold by almost every market stall) would make a nice present...STOP! For the precise reason that it's the very time of year that tulips are looking their best, the bulbs you're buying won't do anything. Otherwise they'd already be...tulips! (fact garnered from the Tulip Museum, which explained why they had bulbs for every flower other than tulips on sale. I just thought they were really stupid.)

If anyone knows what this plant is, I'd be interested to know. Hint: I had completely forgotten what colours it really was by the time I coloured it.