Fresh flower bouquets are wonderful and can last much longer if, besides all the usual methods of adding conditioner/aspirin to the water, and freshly cutting stems and so on, you PRUNE your bouquets. Rather than just throwing out a bunch of flowers that has begun to wilt, change the water, and cut off/throw away the wilting foliage or flowers. Often you can end up with a smaller bunch of flowers which you can then rearrange and you will find that what remains will be quite fresh and will last another few days or a week or more. (I have even rescued cut flowers tossed by my neighbors, pruned them and had a few unexpected flowers to put in a vase and enjoy....)
By Pamphyila from L.A., CA