Thursday, May 31, 2012

Small-leaved Pennywort

Hydrocotyle peduncularis
At the other end of the size scale from last week’s plant is this dainty little pennywort. Its 1cm leaves, almost circular, have five scalloped lobes.

It’s a perennial plant which makes a pretty carpet of soft, fresh green at the water’s edge (both in and out of the water), and mixes happily with other small plants. As with all the Hydrocotyle species, the flowers are inconspicuous.

 Here it is with Pratia pedunculata (oval leaves and small, pale blue flowers) and Utricularia gibba. The latter is the plant with yellow flowers and green thread-like stems, an insect-eating plant which keeps the whole assemblage mosquito-free and allows me to grow water-loving plants without creating a potential disease hazard.

I planted none of them. A shallow muddy area, created in the corner of the birdbath to grow rushes, proved to be a suitable place for the others to appear. I imagine the seeds were brought in from other watery places by the birds.
(See Nov 2008 for more on Utricularia gibba)
Plant lovers can be odd people. In damper parts of Australia than ours, this pretty little native spreads into lawns, something which offends people who like their lawns to be monocultures. Many of the internet references to it, therefore, describe it as a “weed”.
Meanwhile an American plant called water pennywort Hydrocotyle ranunculoides was so valued as an “ornamental” that people have thought it worthwhile to introduce it into Australia, where it has gone on to become a watercourse-choking weed that now costs many dollars to eradicate.
You would really wonder why our own native Hydrocotyle species, attractive plants with no potential to cause environmental damage, are so rarely grown.


Tom said...

Hi Trish, thanks for these last two posts - it has stimulated me to try and ID some similar plants I have in my yard. I suspect they are hydrocotylesp and one maybe a ranunculus. I need to get into my reference books!

Patricia Gardner said...

Keep up the good work, Tom.