Re: What will happen to flowers if you put them in salt water?

Cut flowers are routinely placed in a sugar solution to provide them with 
energy. Cut flower preservatives contain sugar. If you add too much sugar, you 
could harm the flowers as you can with salt.

If you add enough salt (sodium chloride), you can dehydrate the flower and 
make it wilt. Plant cells attract water by having a higher concentration of 
salts or other dissolved compounds inside the cell than outside the cell. 
Water movement across a cell membrane is termed osmosis. Normally, water moves 
by osmosis from moist soil into the plant. If you reverse that by having a 
higher salt concentration outside the plant cells, then water moves out of the 
cell, causing plasmolysis and wilting. Plasmolysis is often observed by 
students with a microscope. Salt will not be beneficial to cut flowers.

References


Re: Why did a flower in SPRITE last longer than one in water?


Re: What is the effect of saltwater on freshwater plants (elodea)?