The latest evidence that colourful and fragrant blooms have been there at the funerals for a long time was provided by the remains of flowers that were found in Stone Age Natufian graves.

Nadel and his colleagues found four graves in Raqefet cave in the Haifa district, which were dated to 13,700 - 11,700 years back.
They found that the graves were lined with flowers; they also identified sages and figworts' imprints in the mud around the bodies - the earliest proof of plants being linked with funerals.
They believe that the plants were laid out beneath and under the bodies of the dead, and were put in a layer thick which was enough to prevent other objects in the grave from leaving their own imprints in the mud.
Source-ANI