Like Robert Frost, Wilbur focuses on everyday experiences and domestic chores. For Wilbur, daily life informs the human condition. More so than Frost, Wilbur adds the lyricism of comedy in his poetry.
"The Juggler" is whirling dervish comprised of dualities: there are two juggling shows, the five red balls versus three domestic items (the table, broom, and plate). It's a poem full of cosmoses: it moves from earth to heaven and back to earth again. He's saying that one need not go to the circus or even look toward heaven to see a juggling show: we are all jugglers of the everyday.
If you ask a juggler how to juggle, he will tell you that you have to start with two balls, then three, and so on. Once you've mastered balls, you may move on to more complicated items to juggle: rings, bowling pins, knives. Eventually, though, no matter what goes up must come down. Wild rides are brief. So why not a table and plate? Why not spin a broom on your nose? Ouch!
Wilbur is saying that we all juggle. If it's not red balls, then it's cooking and cleaning and picking up the kids and going to school and talking on the phone and doing homework. It's a wild ride that we take for granted, but it's no less an act that needs applauding. Sure, we may not dress up and perform on the stage, but we have all made a heaven on earth by shaking up our gravity. And, boy, is it tiring.