In a series of trials covering four seasons, researchers at Cornell University tested various pairings of bulbs and perennials to find the best combinations. See the results here.

 

A sampling of the best at trials:

* Hyacinthus 'Jan Bos' with penstemon 'Husker Red' – The emerging penstemon leaves are dark purple just as the hyacinth is blooming, creating a nice color scheme. It seems as though many cultivars of hyacinth can be combined with Penstemon 'Husker Red.' The penstemon is slow enough to allow the hyacinths to finish blooming and reenergize their bulbs, and then takes over before the foliage becomes unsightly.

* Narcissus 'Slim Whitman' with Achillea filipendulina 'Gold Pallette' – The leaf texture of the emerging achillea offers contrasting texture, adding to the interest of the spring garden. The achillea foliage grows tall and thick enough to hide the fading narcissus foliage.

* Tulipa 'Queen of Night' with sedum 'Matrona' (pictured) – The purple tulip flowers complement the purple-edged foliage of the sedum to make a truly wonderful spring display. The deep, dark purple of the almost-black tulip flower echoes the hues of this dark-leaved sedum. The sedum then grows large enough over the season to overtake the old tulip foliage. This combo would be effective with any upright, dark-leaved sedum.