I added a 'Ghislaine de Féligonde' rambling rose to my garden last year and it has come back double the height and with even more blooms this spring. I've managed to achieve such a full and prolific display by keeping on top of seasonal tasks – and June comes with its own set to tick off.
If you also grow a rambling rose, you likely have a gorgeous, fragrant display right now (though, exact blooming time depends on the variety). This means some light pruning, tying in new growth, and deep watering is essential to do now for early summer care that extends your display until fall.