Wonderful Gardens in Warsaw
It has been hard to choose which garden to visit in Warsaw. So far, I've visited 3 beautiful ones:
Lazienki Park - this nature "museum" (as they call it) feels like it's on the scale of Golden Gate Park or Central Park, with royal palaces - peacocks still wandering, but no royals - ponds and bridges and the Chopin Monument where they stage the free Sunday performances. It's amazing how the few thousands of Sunday concert goers can disperse into the enormous grounds and enjoy the walks and casual paths.
Tip - the group tour dropped us at one side of the park, walked us past the most beautiful areas and, after 45 minutes, picked us up on the other side. Or allow a long half day to do the same at your own pace with city buses. If I lived here, I would bring a picnic.
Saxon Park - just off the side of the Royal Way, this park is an easy anytime break from the busy city streets. It has wide, flat paths, fit for ladies in long gowns with parasols to stroll through the manicured gardens; and 21st century girls in more practical sundresses and tennis shoes.
University Library Garden and Rooftop Garden
Close enough to go for an hour, or stay to read a book or watch the sunset from the roof. Lots of students and non students relaxing in the grassy areas.
Tip to get to the roof: from any of the open street entrances, walk partway back into the park and look to the right to find the outdoor staircases that climb up to the small greenery covered dome and terraces. From the occasional seats, you can view the Palace of Culture on one side and the river on the other.
Summary
Saxon Park and the University Gardens are both great for an hour break from the city sights, or to take a break after a museum.
Lazienki Park requires its own plan, probably on Sunday with the free concert, in which case it's pretty much the entire day, allowing plenty of time for transit or a long walk.