The capital's colourful, sweet-smelling floral celebration is back for another year.

The Canadian Tulip Festival starts today and runs until Victoria Day, May 21.

Tulips bloom on the front lawn of Parliament Hill in Ottawa last year, when there was concern about flowers blooming too early. This year, organizers said tulips wouldn't bloom too late after a chilly April. ((Adrian Wyld/Canadian Press))

The National Capital Commission, which bills itself as the capital's official gardener, said there will be nearly a million tulips in bloom throughout the festival.

There are 100 varieties of tulips, including this year's signature flower: the yellow "World Friendship" tulip, in "the symbolic colour of friendship," the NCC said in a news release.

The 'World Friendship' tulip, developed in 1998, is described as 'strong-stemmed and highly resistant to disease.' (National Capital Commission)

Nearly a quarter of the tulips are planted at Commissioner's Park on Dow's Lake, which features plenty of food and drink vendors. Other tulip beds can be found at Major's Hill Park, Jacques-Cartier Park, Lansdowne Park and elsewhere.

Big, decorative tulips made of fibreglass are also being set up across Ottawa-Gatineau, as usual.

The festival's roots (or should we say, bulbs) date back to 1945, when the Netherlands sent Canada 100,000 tulip bulbs as a token of appreciation for the role Canadian soldiers played in freeing their country during the Second World War.

Once the festival is done, the NCC plants more than 100,000 annual flowers in many of the flower beds, which are in bloom from late July to September.