Plant Profile: Hardenbergia violacea (Purple Vine Lilac)

Latin name: Hardenbergia violacea ("har-den-BERG-ee-ah vy-oh-LAY-sha")
Common name: Purple Vine Lilac or Purple Coral Pea Vine
Originally from: Australia
Blooms: Masses of small purple pea-flowers cover the plant in late winter.
Light: Full sun.
Water: Winter rain is enough.
Height x width: Vining to 12-16'
Zones: 10a -11
Where to find in P. Garden: Far in the back, by the compost bins, covering the fence.

Back in 2009 we were looking for very tough, drought tolerant and evergreen vines that would cover ugly things like fences at the garden. This one fits the bill! I don't think I bought this plant though - someone donated it. And it was pretty scraggly... it limped along for a while in a very tough spot getting no water because I thought it was doomed and the hose didn't reach all the way there... 

Well, somewhere along the way it found its feet and sprang into life, covering the chain link fence it was suppose to cover (and which the Bougainvilleas planted at the same time failed to help with - in fact they died, which tells you how tough the Hardenbergia is)

This evergreen vine has really pretty purple flowers with a chartreuse spot in center covering the plant from winter to early spring. It enjoys sun or light shade in hot inland areas, and tolerates (and even prefers) heavy soil so long as it drains well. 

Happily for us it requires little water once established, and if we could be bothered it would respond well to pruning - hard pruning can reinvigorate older plants. 

The species is widespread through much of Australia and can be found in Queensland, New South Wales, Victoria, Tasmania, South Australia and Tasmania where it grows from the coast to up into the mountains. 

Having a long, carrot-like root, it was reportedly used as a substitute for sarsparilla by Australian aboriginal bushmen. As a result, it also has the common names Australian Sarsparilla and False Sarsaparilla. The Australian aboriginal name for it is Waraburra.  

Dutch botanist George Voorhelm Schneevoogt first described the plant in 1793 in Icones Plantarum Rariorum based off cultivated plants that were thought to be from seeds collected in the Sydney area. Originally in the genus Glycine (the genus of the related soy bean Glycine max) this plant was later combined with Hardenbergia, a name Bentham used in 1837 when describing Hardenbergia ovata. 

The name for the genus honors Franziska Countess von Hardenberg, sister of the Baron Karl von Hugel, a 19th century Austrian patron of botany who collected plants while on an expedition to Australia in 1833. I can't find a photo of Frenziska, but I did find a pic of George Voorhelm Schneevoogt looking smug.

Worst weeds, ranked!

Last volunteer day we did a lot of weeding, and I asked each of our valiant volunteers what was their favorite, or most hated, weed. Well the results are in!

Chris has no fondness for Fumaria capreolata, or White Ramping Fumitory.  This weed is delicate and ferny, but man does it grow quickly! Turn around and it's smothered the plant it "ramps' up onto using it's little tendrils. 

In some ways it's not that bad because it's an annual, and it comes out pretty easily when you pull on the roots. On the other hand, it's awful because it grows and sets seeds so lightning fast that it's impossible to eradicate, and if you grab the stem it's so soft that it breaks off easily.

Jen pulled up this beastly Malva parviflora (read the Weed Profile here) and as you can see this weed is truly awful no thanks to its huge roots. If you don't get the root out, you can expect this one to come right back too. 

Another hateful thing about it is that it seeds quickly and those seeds can sit dormant in the dirt forever. Ugh.

Leslie told me about her most hated weed in the world, but as it turns out we don't have that weed at PG! Miracles. But her second most hated weed is ivy.

Way back when they were building the freeway, ivy was planted at this location on purpose as a ground cover. And I would say it's a great choice - as long as that is the only plant you want. Its ropey vines are impossible to remove completely, so we simply give it a haircut whenever we see it, with no hope of getting rid of it for good.

And John? John's favorite weed is Oxalis (read the Weed Profile here). When I say "favorite" what I mean is he actually likes it. John likes the acid yellow flowers and the cute shamrock leaves I guess? John also likes to pull my leg... so maybe he was kidding...

Oxalis, the bane of many gardens, is impossible to get rid of because it produced millions of tiny bulbs underground... just ugh!

Weed profile: Oxalis pes-caprae (Sourgrass)

Latin name: Oxalis pes-caprae ("ox-AH-liss pez-CAP-rye")
Common name: Sourgrass, Soursob, Oxalis, African wood-sorrel, Bermuda buttercup
Originally from: South Africa
Blooms: November to April
Worst feature: Dreadful replicating bulbs
Best feature: It's edible!
Height x width: 6-12" x 6-12"
How best to weed: Just pull the tops off... you won't find all the bulbs
Don't mistake it for: Any of the ornamental Oxalis cultivars that people buy and plant ON PURPOSE (!)

Oxalis is a genus of the devil. I mean I would call the entire genus an invasive, noxious weed but as it turns out there are a few ornamental Oxalis species and cultivars that people like to grow for fun, but when I see them for sale I either laugh or resist the urge to dump the pots in the nearest trash can.  Even I, as a newbie gardener, planted Oxalis about the place. SMH.

What makes it a bad weed is the fact that it's very successful at reproducing thanks to all the little underground bulbs it makes - they're impossible to dig out, and when bringing in new soil to your garden, unless it's guaranteed to be free of them can easily be contaminated with little bulbs. 

And you may ask "is that where one of the common names (soursob) comes from - the noise gardeners make when they see it growing?" No. The sour part is from the sour taste it has - due to large amounts of oxalic acid in the plant.

Is it all bad? Well, it contains large amounts of vitamin C. You can eat the leaves and (boiled) roots - it's "reasonably" harmless to humans and livestock, which is really all you can ask for in a foodstuff. In South Africa it is a traditional ingredient in dishes such as waterblommetjiebredie ('water flower stew')) and a yellow dye can be made by boiling the plant too.

On the whole thought I think you can tell I don't love this plant. I do find it a useful social litmus test though. Do you find acid-yellow a nice color? Do you like to see fields and gardens full of that shade?  Then, with notable exceptions (John...) we cannot be friends.