Alys Fowler: water lilies

Nymphaea pygmaea ‘Helvola’ likes water 30cm or so deep. Photograph: Howard Rice/Getty Images

Last year our tiny pond grew a huge population of tadpoles that seethed and wriggled in its inky depths. My husband worried, were they eating enough?

So we took to the internet to find out what tadpoles eat. It suggested cooked chicken pieces, fish food and lettuce leaves, all finely cut for tiny mouths. I read the ingredients of my dog’s food and fed them that instead. It turns out feeding tadpoles is frowned upon. Nature knows best, and not all tadpoles develop at the same time. You just leave them to it.

In fact, tadpoles can overwinter and mature in spring if the weather is mild enough, and lo and behold, at the bottom of my puddle lurk a few sleepy teenage tadpoles. This may even be a strategy: if you are out first in spring, you have an advantage over summer-born cousins.

Ponds are brilliant in this way: they turn the idle contemplator into a keen amateur naturalist. Plus I’ve developed a bit of thing for miniature water lilies – all perfect excuses for another pond.

Unless I radically reorder the garden, there’s not room for another traditional pond, so I have improvised and made an even smaller one in an old fish tank (tub trugs and large buckets are just as good). Life likes water whatever the size, as long as there is a way in and out. Some sort of exit strategy is essential, particularly for frogs, toads and newts: a stick for use as a ladder, a few old bricks and stones, say. So are plants, otherwise the water becomes stagnant, but in small ponds you need small plants. Go to a specialist water plant nursery: many sell by mail order and you get what you pay for. A generic water lily can easily grow into a monster.

If you use mail order, make sure your pond is ready to go; once plants arrive, they need to go straight into water. A good nursery will send clear instructions of how and where to place them. Nymphaea pygmaea likes water 30cm or so deep. The flowers are small, too, 3-5cm across, but that makes it all the cuter. You can have pink (‘Pygmaea Rubra’) or yellow (‘Pygmaea Helvola’). ‘Aurora’ has a slightly larger spread, opening yellow and turning a reddish-orange. Or there’s the pure white, double-flowered N candida.

For shady ponds, there’s the water forget-me-not (Myosotis scorpioides) or Anemopsis californica, which has beguiling flowers that smell of honey. Order soon, because you want your plants established before the tadpoles get big – a happy plant can cope, an unhappy one won’t. And if tadpoles do start devouring them, offer lettuce as an alternative. Just don’t say I told you to.