If a florist's porous foam material is used in assembling the arrangement, it is important that it is thoroughly saturated in advance in water containing a floral preservative. Be sure that the rose stems are inserted firmly well below the solution level in the container. Do not move the stem ends after inserting them into the foam. This may leave an air pocket at the base of the stem. Display your fresh cut rose arrangements in a cool area out of direct sunlight and drafts.
Roses are thirsty flowers.
It is important to check to see that the vase is full and add preservative solution often. Be sure foam materials are completely saturated and the container is full daily. It usually indicates that air is entrapped in the stem and the preservative solution can not flow properly up the stem. The end of the stem may be blocked, or look for a cut or scrape in the bark above the water level. Be sure to keep the stem and head straight.