Malbuk,
Rhubarb,Cannas,Butterbur,Catalpa tree,Castor beans, and Hosta are all great choices.My friend makes leaf castings and Loves giant leaves.I live on a busy boulivard with a 40 MPH speed limit.So I need them for the wow factor. Slows the traffic down because of the gawkers.LOL Why do you want big leaves?
Segra

Try hosta "Sum and Substance." It's in a league of it's own, with 16" wide leaves and 6' wide clumps.

Regards,
Firevicar

Darmera, Petasites gigantea, Alocasia, Colocasia, Tetrapanax with protection. Fatsia japonica, Brugmansia, Fig trees, Paulownia trees, Cardoon, Heuchera,Acanthus, Rodgersia. I also grow Lotus in big tubs. You can bring them inside a greenhouse or non-freezing garage in the winter if the temps. get very frosty.

You can't beat Ligularia for large leaves AND long flowering period. I recommend 'The Rocket'. Prefers partial to full shade and moist rich soil.

The petasites gigantea also comes in a variegated form, which is lovely. These are very nearly bog plants, though, so I don't know if this is what you are looking for. Also Hosta "Blue Angel" gets very large blue-green leaves, as does Salvia 'Clary Sage'. It is bienniel, but will reseed itself prolifically. If you're looking for a small tree (20' tops), I have a contorted mulberry with very large foliage, plus it provides interest in it's contorted branches even in the winter (morus bombycis unryu). It's kind of hard to find, but I'm sure someone carries it. It also grows faster than Harry Lauder's Walking Stick, and has larger leaves (about 9"). Also, no messy berries like some mulberries. Hydrangeas (the mopheads) have large leaves on them, and are best in shade. You don't say whether you have shade or sun or in between, or what zone you are in.

You do say you like aroids, and some are hardy to zone 7 with protection, like the colocasias, alocasias, etc. I have regular elephant ears in my yard as well as the upright variety. I just put bags of mulch over them and they winter over fine.

Bergenias also have large leaves, and are an excellent ground cover, with lovely flowers.

SusanLynne

sambucus'black beauty'
9" dark purple leaves

it's not hardy, but taro bulbs are easy to dig up in the fall when you dig up your sweet potato tubers for next year...

and since a regular green 'elephant ear' sells for $4 for a bulb, and up to $15 for a growing plant... it's kind of funny to me that you can buy taro roots in most big grocery stores now for $2 a pound! I tried two of them (cost less than a buck) and they're both doing great- I might try bringing them in in pots for the winter!

prairie dock

Check your library for Myles Challis' books 'Exotic Gardening in Cool Climates' and 'Large Leaved Perennials'. He gardened in London and was my inspiration when I saw a magazine article about his garden in London years ago. l promise you'll love his books. josh

Try musa basjoo, it's hardy to zone 5 and it really packs the wow factor.....my leaves get to 3 feet and bigger.

Hosta"Big Daddy" is the biggest hosta I've ever seen. I also have a plant with big leaves which blooms yellow flower in summer and prefers part sun or shade. I lost name tag and hope someone tells me.

For an annual, try the big nicotianas: n. mutabalis(I grew this variety this year and it reached 6' but the flowerswere paltry, small pinkish-white and few - leaves were about 2.5'x 1'W); n. sylvestris, n.alba. Stunning plants that will take just about any siting without complaint. Bugs and diseases don't seem to like them at all - probably b/c they are in the tobacco family.

Wow! Thanks for all the suggestions! I love making leaf castings, but was getting a little tired of Elephant Ears. What fun to start shopping for goodies for the spring.

Has anyone mentioned Gunnera manicata yet? Leaves can be 6' across. Put it in an enormous pot if you want to curb its enthusiasm a bit.

So you want REALLY BIG leaves? Have you ever encountered a taro called Colocasia gigantea Thailand Great Strain available from Plant Delights Nursery (www.plantdelights.com) or a water lily called Victoria which is big enough that you can walk on top of it, available from Tricker's Water Gardens (www.tricker.com)??? Don

Colocasia gigantea Thailand Giant Strain:
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Victoria:
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Thank you Don, those are amazing..........Wayne

That colocasia is AMAZING!!! I really want one... I just saw that it's okay to zone 8, woohoo! Anyone know where to get one in the UK? I have a perfect spot to put one of these.

Anyone know of a place in Ontario Canada, that seels the bulb for that colocosia?

haha. there's a picture in my american history textbook of eleanor roosevelt standing on one of those lily pads, i think it was taken at the national zoo.