A kind ship mate (Babs), told us about this coloured-water experiment with flowers. So, we enjoyed a happy half hour gathering white flowers (thank you "no mow May") and another half hour splashing around with food colouring and water (outside!) to make some jubilee-coloured water.
Alas, they weren't very thirsty flowers so the results are still pending... fingers crossed for red, white and blue flowers soon!