I could be wrong (and I usually am) but it puts me in mind of Brugmansia or Datura which have large trumpet like flowers. Someone will know.

Brugmansia would be my first guess. Do any of your neighbors have a large shrub or small tree with long, pendulous, trumpet-shaped blooms, Mlooi?

(snap!) I was writing while you posted Cammomile! :)
Datura is also a possibility, and they are more prone to self-sowing, but they usually have a purplish tint to the stem.

Cammomile and Tugbrethil, thank you very much for the posting. It certainly looks a bit like Datura when I search on the web. It has not start flowering yet so I cannot verify it. Will let you know when it starts flowering.

Do they flower in the Autumn in Oz? My daughter lives there and it's mighty hot at the moment.

It's a whole continent, Cammomile, with different degrees of heat. From what I hear, Alice Springs would be about as blazing hot as us folks in southern Arizona experience in early September--too hot for Brugmansia to bloom, even in the part shade they prefer, here. On the other hand, Sydney would be medium hot, about like Atlanta, Georgia, in the States. I don't think that anyplace in the UK gets hotter in the summer than Australia's highest elevations, where the Snow Gum grows. Mlooi obviously knows better than I, and may be blowing justifiable raspberries at me now! :)

I'd say Brugmansia rather than Datura because Datura usually has rather spiky leaves. Not 'spiky' spiky but just not as smooth as Brugmansia.

Thank you Thepoisonga. We would know one way or the other when it starts flowering. Will let you guys know.

Tugbrethil, it does not matter where we live in Australia anymore, the weather is so hot this year. I live in Sydney and Jan and Feb this year is constantly at high 30 degrees Celsius. Many days were over 40 degrees Celsius and one day it was recorded over 50 degrees Celsius. It is as hot as Alice Spring or even hotter. In the past, in Jan and Feb, our range of temperature would be high 20 degrees Celsius and low 30 degrees Celsius. I believe in global warming.

Wow!! Summers here in Phoenix usually run around 45º C, but 50º is rare for us. Our share of global warming has mostly been visible in night temperatures and drought. Well, my info is probably obsolete, now. Stay hydrated, Mlooi!

Yes my daughter lives in Manley near Sydney and is finding the weather rather hot at the moment. She came home for Christmas and we had to supply a hot water bottle each night for her!

I finally found what I think this is called. I had to ask a friend, and the Portuguese name for it is Forna de Porca. The real name is Solanum mauritianum. It is from South Africa, and grows as a very invasive plant here, reaching 5 meters tall if left alone. At least that is my guess.