Members of the Pakistan Awami Tehreek (PAT) and the Pakistan Tehreek-i-Insaf (PTI) began their protests Aug 15 in an attempt to topple Prime Minister Nawaz Sharif who has been accused of rigging the 2013 general elections.
Since then, the protesters have continued with their sit-ins in Islamabad.
The bouquets have been placed in front of the parliament house, lining the road.
The words 'Inquilab March' have also been written with flowers on the nearby greenbelt.
PAT media coordinator Ghulam Ali said the flowers have been sent to show solidarity with the people who sacrificed their lives and faced injuries during the ongoing protests.
"The flowers have increased the determination of the participants," Ali said.
The protesters Thursday agreed to vacate the Constitution Avenue, where the parliament house and the Supreme Court are situated, for a new site.