I have never heard of them being invasive...Anyone else?

I have only heard of them being invasive (as in spreading quickly) in the garden in damp areas, never in pipes.
Cheers,
Dee.

What are elephants ears? Common name for what plant?

(In some parts of the world elephants are invasive)

I have a couple of what I think are elephant ears in my backyard, one of them was planted about 12 months ago is HUGE now, but it hasn't spread, it's leaves just grew really big! It is in a damp spot in our garden and I like it so much I have planted a couple more close by. I hope they get just as large as the first one.

Do they flower or are they just greenery?

Ange

I have some growing and they are not going anywhere meaning in width or height.
Got them from my sister in Melbourne last June they dont seem to like my side garden.
Too dry probably as I only water once a week but a 3/4 acre block takes heaps.
I believe they like the damp, so they wont get it in my garden.
They belong to the Colocasis family including the Alocasia that has real pretty leaves.
No flowers, Have a look at the link below little info there...Cheers..MM.

Here is a link that might be useful: Elephant Ears

Thanks - that's interesting because a friend used to grow a bulb that she called elaphant ears, and it had a flower of some sort. Don't remember what. It certainly didn't look invasive!

The one I grow definitely has flowers with a most beautiful perfume. The form is somewhat like the Spathiphyllum (peace lily) but more of a greenish colour.
Cheers,
Dee.

You only have to do a google to find the following.

This is from Weeds Australia.
"Taro is dispersed by water and humans and although first recorded as naturalised only in 1996 it is now spread along many creeks and rivers.

It has the potential to become a major weed along Queensland tropical and subtropical coast and northern NSW."

This is from a Gardening Australia program on weeds.
"But allow taro to escape into the wild and it becomes a serious weed. In fact, it's choking streams and rivers across Eastern Australia."

I am surprised you Northerners are not so aware of this.

Thanks for all the responses. Robert, mine will have no chance of escaping into the wild but appreciate the warning.

mine definitely has flowers, sort of longish yellow/green and scented. Not much to look at though

It also has grown rather large under a shadecloth covered area, but I just yank on a large section and it snaps off easily; resprouts easily too. Mine don't get much water; though maybe they survive on the seepage from a tree fern about a metre away

I have a few growing, in one area they only get water a couple of times over the dry summer and they behave really well and are much more drought tolerant than the books will tell you. another one is in a garden bed which gets watered from the retic and even though it's not a lot of water, I find that one a bit of pain because it does a little too well and it keeps sending up lots of pups which I dont really want in that area and I cut them off with a spade to keep it from taking over. I think if you give them plenty of room they wont be much trouble and as long as the drain pipes are in good condition then the roots shouldnt really be able to get in?

Sorry if I offend anyone, but this issue comes up from time to time. The use of botanical names does not completely save confusion, but it sure does help.
The elephant ears I am familiar with would be the haemanthus mentioned below.

From the internet:
Common names can vary from country to country, and region to region.
The botanical names are used worldwide, and are established by the "International Code of Botanical Nomenclature".
Unless you knew the botanical name, it might be hard to figure out which Elephant Ear you were talking about.

Alocasia odora is a tropical plant from Borneo, and Asia.
Colocasia esculenta is the common Caladium, grown from bulbs.
Philodendron bipinnatifidum is the common houseplant, Philodendron selloum.
Haemanthus albiflos is a bulb grown plant, belonging to the same family as an Amaryllis.
Acacia dunnii is a 20 foot tree, native to parts of the United States, as well as Australia.

just looked it up, and found a drawing on the Australian National Botanic Garden site of Alocasia macrorhiza, which is the elephant ears that grows in my garden

the url is
http://www.anbg.gov.au/poison-plants/poison-PDFs/Alocasia-macrorhiza.pdf

Sparaxis, I agree it can be very confusing using common names. I know of a number of plants commonly known as Elephant Ears or Elephants ears.

Taro or Alocasias, Colocasias, even Bergenias etc. Some are not potential weeds, while others are already causing problems in waterways.

Having looked at the suggestions that Jan has made, I have come to the conclusion that my 'elephant ear' is probably Alocasia odora. Mine does have a wonderful perfume and the growth habit looks the same.
Cheers,
Dee.

mine looks more like A Brisbanensis below, except a section of the flower on mine turns pink after a while

Here is a link that might be useful: A Brisbanensis

Brizzie,
there are two groups of elephant ears. One group consists of solitary or "clumpers" which spread very slowly by producing offsets. The native elephant ear Alocasia brisbanensis, or whatever it is called nowadays, falls into this group. There is little risk of it escaping or spreading even in damp conditions (they may spread by seeds though). The other group are "runners" which form long "rhizomes" and which form a new plant at the end. The dark purple Alocasia plumbea is an example. Running elephant ears may spread quickly, especially in damp soil and in good conditions. These are the one to look out for regarding weed potential. All of them will flower but flowers are generally insignificant, but some are fragrant.