Can you zoom in those seed heads? They look like something in the Ranunculaceae.

Hydrocotyle moschata var. moschata, Hairy Pennycress

Duh! Of course. I was fixating on those buttercup-like fruits.

Floral, do you happen to know why 'penny' is used in many old common names. It's usually combined with 'cress' or 'wort'. Maybe all the plants could be bought with one penny? I'm thinking 'penny' may have been commonly used even before we started minting pennies. What is a penny in the UK? Cress I guess, means any Brassica? Wort means what? I googled penny, but nothing comes up except 'wort'.

Yes that's it! Pennywort. Thanks. It sure makes a nice ground cover.

You're welcome John.

A penny is a coin. Nowadays there are 100 in a pound but before decimalisation there were 12 to the shilling and 240 to the pound. They’ve been around for well over a thousand years. In plant names it just means there’s a flat, round leaf or seed, like a penny.

Wort is usually a plant that had some medicinal or culinary use. Cress is some sort of peppery flavoured plant, so yes, generally a Brassica.

https://en.m.wikipedia.org/wiki/Penny_(English_coin) 

'Penny' because the rounded leaves have the appearance and are the approximate size of an old penny coin and 'wort' just means plant, herb or root (from the old English - 'wyrt').

Excuse me for saying but an aquatic lover like hydrocotyle seems a very odd groundcover choice for a highly drought prone area..........

An Australian penny was quite a large thing, maybe an inch in diameter. Pennies of long ago would also have been large I think. (I'm probably coming out with the bleedin' obvious - my specialty.)

Thanks everyone

This is a 1967, pre decimalisation, penny. But, as I said above the penny has existed for well over a thousand years in various forms. The tape is in inches.

I think in most instances penny is used to describe plants with round leaves, and not so much the size being close to the size of an English penny.. A pennywort is any plant with round leaves. Everywhere the English empire traveled to has penntworts and pennycresses. Not very descriptive if you want an exact species ID. Now the words false and bastard? False would be a plant that resembles another plant, like ' False Foxglove' Bastard? I guess it must also refer to a plant that resembles another plant, Comandra = Bastard Toadflax. Galeopsis tetrahit is called Hemp Nettle, but it's neither hemp, (Cannabaceae), nor a nettle, (Urticaceae), but a mint, (Lamiaceae).

The leaves are way smaller than a US penny. Even smaller than a dime. Gardengal I didn't plant it, it grows there by itself. Without the irrigation system running I am certain it would die off relatively quickly.

Considering your governor is about to institute mandatory water restrictions, you might want to investigate some drought tolerant groundcovers by means of replacement :-)

And we seem to obsessing about the reference to a penny coin!! From Wikipedia: "In general they all have round leaves of about the shape and size of a (pre-decimal) penny." And a well grown hairy hydrocotyle does have leaves about the same size as a US penny...approximately 20 mm. But the common name was utilized long before our pennies were around.

“In general” .... is about right. There are exceptions eg Field Penny Cress with flat round seeds about 10-15mm diam.

Botanical names use the same descriptive devices as common ones. False and bastard would just be ’pseudo’. Plants are often named with reference to their similarity to other plants, both in the vernacular and in botanical language eg ’salicifolia’ etc.