Packets of seeds are available in store alongside paper chains for people to decorate and hang in the community with messages of hope and celebration.
Community champion Ali Whitburn is also handing out hundreds of each to schools, care homes and community groups in the area.
She said: "We are giving away free packs of cornflower seeds to spread positivity and hope for the future. We chose cornflowers because they are one of the Queen's favourite flowers and she loves blue.
"The Platinum Jubilee is a time for celebration and hope, and through our paper chain messages and community awards we can help celebrate hope in the run up to the long-awaited weekend."
Ali will also recognise and award pillars of hope in the community in four categories as part of the campaign.
She explained: "Hero, Organisation, People' choice and Eco help spell the word HOPE. A hero is a person who goes above and beyond, the organisation will be a charity or community group that does outstanding things, the people's choice will be someone nominated by the community on my Facebook page, and eco warrior is someone who is supporting the local environment."
Cornflowers are being used in the Superbloom display at the Tower of London in celebration of the Queen's Platinum Jubilee. These easy-to-grow wildflowers are great for bees and butterflies and can be sown in June to flower in September.
Rebecca Singleton, community director at Morrisons, said: “It has been a challenging year for many people in the UK and around the world and we want to help spread hope amongst our customers and communities.
"The Platinum Jubilee is a time for celebration, and through our millions of Seeds of Hope packs we want the cornflowers, with their bold sapphire shade, to represent brighter and more positive times ahead.”Also in the news: Towns and villages across West Sussex prepare to celebrate the Queen’s Platinum Jubilee