I am making a cake for my niece's wedding similar to this one...
http://blog.pinkcakebox.com/search/hydrangea

I ordered a hydrangea kit - makes them great, but I thought they were a little heavy. I made a sample spray on wires for her. For the wedding cake - I will be making them without the wires - cake will be fondant. Just wondering how I will attach them and not worry they'll be too heavy - or do I just need to make them much thinner. When I made them thinner - they didn't hold their shape well - do I just let the gumpaste dry some before I press them with the veiner? I can't imagine making and coloring them all when I'm decorating the cake (as opposed to making them ahead and letting them dry).

Also - (sorry for all the questions!) - I've been brushing the color on - and read a little bit somewhere about about "dipping". Has anyone done this? Something about putting the powder color in alcohol maybe and dipping the dried flowers in?

I made a shower cake for her with my sample spray - http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1428796&done=1

When I make flowers I make them thin and I put them in round painting palate to dry (you can use flower formers) you can also shape foil into little cups and use that for drying flowers. I also dust them with powder color. What kind of gum paste recipe do you use?

Hydrangeas were one of the flowers I used for my parents' wedding anniversary cake (see my photos). I rolled by gumpaste thin but not so thin that you can see through the gumpaste or that it would tear when I pressed the veiner to it. I made my hydrangeas on wires individually and then hung them upside down overnight (You should have seen my kitchen with all of these hydrangeas) and once they were dried I dusted them with dry petal dust. I worried too about the heaviness of the bunch and so what I did was made the bunches smaller. For example, one of my standard bunches had 45 hydrangea blossom; a smaller bunch would have about 10-15 and then on the cake I would just but them as close together to make it look like a larger bunch but without the weight. Not sure if that made sense

Hydrangeas, need to be colored with powder dust, to achieve the many colors per flower thats natural of them. Dipping flowers is more to achieve deep color as in a very red rose.
A good gum-paste will accept you to rolled thin without a problem. Bunches need do be made if 10-15 flowers. Wire them, they look more professional in my opinion.
Dry them upside down for 24 hours before painting

I bought buckets of satin ice pre-made gumpaste. I'll try to roll it thinner, and hopefully that will help.

I don't know if you can see the one on pink cake box - but it doesn't look like they are wired at all - they cover the top of the teirs, and then are falling down over the sides. What should I "glue" them onto the fondant with? For the small things I've done in the past - I've just made a "glue" out of equal parts of meringue powder and water or just plain vanilla - but I don't think either of those will work to hold these blossoms on the sides after they've dried.

I did just brush on powdered colors (3 shades). They look nice - but it does take a long time!

Moralna your anniversary cake was beautiful! That's not really the same effect as the one she wants - but it sure is pretty. I do see what you mean about smaller bunches.