The Cherries bounced back from their Capital One Cup defeat to Liverpool in superb fashion to make it 12 league games unbeaten, which in turn left Blackpool rooted 10 points adrift of safety.
Ritchie scored in either half and Callum Wilson also helped himself to his 11th league goal of the campaign in the first period.
Nathan Delfouneso did grab a consolation for Blackpool on 65 minutes, but Brett Pitman, Marc Pugh and Harry Arter goals ensured a comfortable afternoon for the visitors.
Bournemouth had the first opening of the game in the seventh minute, as Ritchie latched on to Pugh’s left-wing corner and fired left-footed from the penalty spot, only to see his effort cleared from the goalmouth by Kevin Foley.
But they took the lead in the 18th minute through Ritchie’s fifth league goal of the season. He cut in from the right and fired a left-footed shot from 25 yards that Blackpool keeper Joe Lewis allowed to bobble over his hands and into the net.
Eddie Howe’s side came close to doubling their lead in the 27th minute through Pugh, who drove at the heart of the defence and unleashed a fierce shot from 20 yards that Lewis pushed away low to his left.
However, the visitors deservedly doubled their lead after 41 minutes through Wilson. Chris Eagles tried to shepherd the ball out on the byline but Charlie Daniels hooked the ball across the box, where Wilson tapped into an open net from three yards.
Ritchie grabbed his second of the game in the 59th minute to make it 3-0. The midfielder picked the ball up on the left edge of the area and curled the ball superbly beyond Lewis.
Blackpool were rewarded for their improved efforts as Tony McMahon’s shot was saved by Artur Boruc but rebounded to McMahon, who squared for Delfouneso to tap into the empty goal.
But straight from the kick-off, Bournemouth won a penalty as Darren O’Dea brought down Wilson. The penalty was converted by Pitman, who had to retake for encroachment into the box, but proceeded to strike the ball home once again to make it 4-1.
Bournemouth continued to pile on the pressure and scored again after 73 minutes as Ritchie’s cross found Pugh, who nodded home at the back post from six yards, prompting a mass exodus from Bloomfield Road.
And Arter made it 6-1 on 75 minutes as he picked the ball up from Dan Gosling and lashed home left-footed into the bottom corner from 15 yards.