I found this interesting article in a magazine from 1946 that gives advice for care of several different kinds of pruned flowers, enjoy!
If you are addicted to using a gathering basket, put it away and substitute it for a sizable bucket. Fill it with water, and into this big drink plunge the stem within the first sixty seconds of a trice after you cut it. This is bloom-preservation principle number one.
A pruned stem, if not put into water at once, begins to suck in air which later will form “blocks” to prevent the sucking up of needed moisture when the stem does finally reach water. The result of such goings-on is a droopy, under-privileged looking thing that will soon lie down and die.
Second principle is proper treatment or “hardening” of the stem so that it can drink up more water and keep the blossom fresh longer. This treatment varies with the type of stem.
Woody Stem Plants, Shrubs
Examples: Chrysanthemums, Lilacs
Hard, woody stem plants, because of their internal structure, usually draw water very slowly. To speed up their moisture intake, smash the cut ends with a hammer for about two or three inches up the stems. This will expose the fibers and allow the stem to take up all the moisture it needs.
Hollow Stem Plants
Example: Dahlias, Delphiniums
The hollow stems of these plants have very little fiber surface and are quite hard around the outside. To open and soften the fiber layer so that it will absorb more water, dip the cut ends of the stems to a depth of four to six inches in boiling water, let stand a moment, then plunge into cold water.
Milky Sap Plants
Examples: Poppies, Poinsettias
In these, the action is reversed from the usual. Instead of the stem sucking up water, it lets its moisture run down, along with the heavy sap. They can be made to last two or three days in water if, when cut, the stems are immediately plunged into cold water and then, as soon as possible, held over a flame for about 30 seconds before being put back into water. Burning forms a callous at end, stops “bleeding.”
Those Requiring No Stem Water
Examples: Camellias, Gardenias, Orchids
These hold a great deal of moisture. They need no water in container, only a light daily syringing of water on blooms. Syringe corsages, keep in refrigerator.
Examples: Marigolds, Cornflowers, Asters
These require nothing more than immediate submersion in water, and placed in cool darkness for several hours.
Examples: Tulips, Lilies, Gladioli
These require immediate submersion in water in deep containers, with all of the stem surface under water right up to the blossom head. Then keep in deep water in the coolest possible place for three or four hours, or longer.
Source: Homemaker’s Digest (1946)