Japan's weather agency said Friday it would stop giving forecasts for the start of the cherry blossom season, an annual rite which sees millions of people flock to picnic under the delicate pink petals.

The start of the spring cherry blossom season is an excuse for drunken revelry across Japan but an annual headache for the Meteorological Agency, which has been trying since 1955 to predict when the trees will bloom.

Weather forecasters have been left red-faced in the past for miscalculating the start of the blossom season. In 2007, Japan's chief weatherman was forced to bow in apology after a computer glitch resulted in the wrong forecasts.

With a number of private weather agencies now giving similar information, the government agency has decided to end its service.

"The agency has given out such information in early March every year but we will no longer do so from next year," said Yoshitoshi Sakai, an official of the agency's observation division.

The agency will continue observing cherry trees throughout the nation to declare the official opening of the flower season and aid studies of climate change, he added.

Hanami -- flower-viewing parties at which lavish picnics are consumed, accompanied by beer or sake -- are planned weeks in advance among friends or by businesses looking to boost employee morale.