A frequent complaint gardeners have about spring blooming bulbs is that their leaves stay around for weeks, marring the image of a neat and tidy landscape.
That’s because the foliage needs to go through a critical process called ripening, which replenishes the under ground bulb with the nutrients needed for next spring’s flowers.
Cornell University researchers trialed bulb and perennial combinations for four years and developed several recommendations that can guide gardeners this fall when they plant tulips, daffodils, hyacinths, crocus and other spring-blooming bulbs.
The best bulb-perennial pairings do more than look good together. They also support each other in the landscape, the researchers said. For instance, the color of tulips, daffodils and other bulbs can compliment the emerging leaves of nearby perennials. As these perennials grow, their leaves camouflage ripening foliage of the spring bulbs.
“The idea of pairing bulbs and perennials to achieve multiple goals is so desirable, that we felt it deserved more than an anecdotal approach,” said Prof. William B. Miller, director of the university’s Flower Bulb Research Program. “We created an objective study to document what works and what doesn’t in a typical spring garden.”
The combination trials were designed to achieve four goals:
- Look at how early bulbs help extend the bloom season.
- Explore how perennials might best be used to mask the dying foliage of spring bulbs.
- Consider leaf texture as a design element.
- Examine the various roles color plays in creating successful combinations.
Cornell’s Bulb and Perennial Combination Web site is divided by recommendations for tulips, daffodils, crocus and other categories. Images for the top 15 combos show the progression of plant growth over the season.
One of my favorites: ‘Queen of the Night,’ a purple tulip, which compliments perfectly the purple-edged, new leaves of ‘Matrona’ sedum. As the sedum grows, it over takes the old tulip foliage. This combo would work with any upright, dark-leaved sedum.