Prospect Park is celebrating its 150th birthday party April 1 and 2, with more than a dozen events and activities that are as diverse as the borough of Brooklyn.

Dog owners, baseball buffs, bird watchers, urban gardeners, ice skaters and art aficionados are among the niche groups that will find their interests addressed.

The park’s youth baseball leagues march every year on opening day, but this year’s parade, setting off at 10 a.m. Saturday from Second Street and Seventh Avenue and led by a marching band, is expected to draw thousands. The young athletes will wind up in Long Meadow’s Field One, where, following a ceremonial opening pitch, the Brooklyn Atlantics — a historic baseball team wearing old-timey white uniforms and playing by 1860 baseball rules — will play an exhibition game.

If historic baseball is not your cup of ballpark beer, an opening day fair at the Bartel-Pritchard entrance is offering food, drinks and introductions to members of the Prospect Park Alliance and community partners, who help keep the park green and clean, beginning at 11 a.m.

“The theme for our 150th anniversary is ‘community,’ ” so the Alliance and the Parks Department want to honor volunteers and promote community involvement, explained Grace McCreight, one of the anniversary’s organizers.

Some events cost money or require RSVPs: Visit prospectpark.org/150 to confirm your attendance and make sure you have a spot at events, such as the 3 p.m. Sunday walking tour, led by Turnstile Tours ($10-$20 per person, with discounts for Alliance members).

Runners can join the 11 a.m. Saturday “Prospect Park History Running Tour” that will stop periodically to appreciate points of interest. For a $3 suggested donation, urban gardeners can report to the Lefferts Historic House at 2 p.m. and join the Alliance in planting a crop of flax. (The 150th visitor wins a mystery prize). Naturalist and birding tours, volunteer activities and a “grill out,” with meats and veggies sourced from Greenmarket farmers, are also planned.

“It’s going to be a great weekend to get out and enjoy the park,” promised McCreight.

But what if — heaven forfend — it rains on April Fools’ Day?

No worries! “Most of the events are rain or shine,” said McCreight.

Visit prospectpark.org for a full rundown and overview of events all park events.