Blue lotus

This is a big spreading water lily with star-like, pale blue flowers about 15cm wide, and distinctive yellow stamens. It needs to be planted in a large aquatic basket filled with aquatic soil, with the sausage-like stem (or rhizome) going just under the surface. Put gravel over the top. The container then goes about 20cm under the water surface, possibly supported on an old brick. Only buy it if you have a large, still pond (avoid running water) in full sun, which will not be choked by its growth. Regularly remove the fading leaves and flowers. Because it needs to be kept at 10C in winter, the basket should be lifted and put in a small, water-filled container in a heated greenhouse. If you can't provide these conditions, buy a hardy water lily instead.