I have to make a wedding cake with minimal decoration because the couple's budget is limited. They want fall leaves. Any ideas?

Using wafer paper and airbrushing on color is the most natural (real) looking leaves one can get.  You could get up to a 1/2 dozen leaves from one sheet.    I'd just make maybe a dozen or 2 leaves and scatter them around.  OR  make a cascade of leaves like this:  http://cdn.cakecentral.com/gallery/2015/03/37WgW8_fall-leaves-wedding_200x200.jpg        http://cdn.cakecentral.com/gallery/2015/02/37Z73c_pollus-red-rose-swag_200x200.jpg    

http://cdn.cakecentral.com/gallery/2015/02/372dPi_ethan-showerjpg_200x200.jpg         

  http://cdn.cakecentral.com/gallery/2015/02/377YpY_pearls-and-lace_200x200.jpg         This one shows how you could make a couple of small groupings of leaves

Yes,  the last 3 aren't fall leaves but the design idea is what I was referring to :)
One can also make leaves from gumpaste or fondant somewhat like using wafer paper but I find those heavy and not as real looking. 

http://www.cakecentral.com/gallery/i/3144245/small-wedding-cake  

http://www.cakecentral.com/gallery/i/2410209/red-amp-white-hearts  

http://www.cakecentral.com/gallery/i/3295955/sponge-cake-filled-with-whipped-cream-meringue-drops-and-dulce-de-leche-iced-with-smbc-tree-leafs-are-candy-melts   

http://www.cakecentral.com/gallery/i/3341042/wedding-cake  

Look at the cakes above and see if it inspires an "idea" for your cake.  Quite often I will go to my gallery of saved favorites and combine elements from several cakes into "my" cake.

You can also enter the search term into the CakeCentral search box:  autumn leaves

Here's one of my favorite, very elegant, brilliant autumn wedding designs:

http://www.cakecentral.com/gallery/i/2856977/elegant-fall-pumpkins

             I like this one!  Still fall leaves- but all white!

Just some inspiration to get the imagination flowing......     :)

for inexpensive -- i'd do something like this where you stripe the bag of buttercream --advance to 2:15

and i put orange, brown, green and red stripes of icing then fill with gold all in one bag -- so pretty so much fun so very inexpensive  and cascade them or whatever -- i'd add tendrils too for contrast -- maybe a couple acorns --

but for a wedding cake i'd have my icing a little stiffer still on the loose side but i'd want the leaves to stand up more

UUUggg just saw those mistakes in my post :(  Don't know how that happened.  If you go to my album you can see some ideas that should have posted in the above.

This is one of my favorites I've been saving !

Sorry - I tried to copy the picture!  And my type is covering up my pasted link!?!  Grrrrrr

Theresa

http://cdn.cakecentral.com/gallery/2015/02/58189gwyN_retrocontemporary-baby_900.jpg

you could make this all white-on-white or a color

@theresaf ~ that's darling!  It's going in my favorites too.

And for all the times I haven't been notified of an update to a thread -  I just got 5 notifications that Apti replied!

I did reply.

I did reply.

I did reply.

I did reply.

I did reply.

lol.....