Some plants just seem to be made for each other. You put them together and watch the sparks fly. Maybe it's the sizzle of complementary colors or a dazzling mixture of form and texture. April is a great time to play matchmaker, when nursery shelves are brimming with gorgeous spring-blooming annuals and perennials. Make your choices, and let instinct be your guide ― just take care that the would-be partners require the same conditions ― exposure, water, and soil ― and bloom at roughly the same time.

MAKE MAGIC IN SHADE

Lime-colored foliage often gets a bad rap. But it can play a strong role in the garden, as a foil, backdrop, or spotlight. Chartreuse foliage brightens somber purples like heliotrope and provides a lively backdrop for marine blue summer forget-me-nots (Anchusa capensis) or blue-red amaranth plumes. In a shade-loving container combine lady's-mantle, nicotiana flowers, and lime-leafed coleus, which provide the chartreuse notes, while deep purple heliotrope tempers the green glow.

A CHEERFUL TRIO

In early summer, the fluffy white flowers of Spiraea nipponica tosaensis 'Snowmound' bloom in concert with the yellow trumpets of lemon daylily (Hemerocallis lilioasphodelus). Later, when common chives at the front of the bed burst into bloom, their rosy lavender blossoms turn the harmonious duet into a merry trio. All three plants have similar needs: They bloom best in full sun and well-drained soil. A light feeding in early spring and regular water during the dry summer months keep the show coming back year after year.

PURPLE PARTNERS

This palette of unthirsty perennials thrives where summers are dry. Most prominent among the airy flowers is Trachelium caeruleum, a Mediterranean native whose dome-shaped blooms float on tall dark stems. (If you can't find it at your nursery, try Limonium perezii.) Flank the Trachelium with creamy flower heads of Achillea 'Anthea' and lavender-flowered catmint (Nepeta x faassenii). In the rear, wavy purple plumes of Mexican bush sage (Salvia leucantha) can play off spiky red leaves of New Zealand flax (Phormium tenax).

OTHER GREAT MATCHES

These combinations offer both interesting foliage comparisons and striking color pairs, such as blue and chartreuse.

• Crisp, erect, purplish blue Dutch iris (such as 'Blue Ribbon') poking out of billowy chartreuse Euphorbia characias wulfenii is a spring showstopper.

• The large blooms of a pink rose (such as 'Simplicity') mingle sweetly with clusters of small, blue lily-of-the-Nile (Agapanthus) flowers.

• Japanese barberry's chocolate tones dramatically mirror the brown centers of deep yellow black-eyed Susans.

• The stately spires of foxglove watching over a swath of pink and blue florists' cinerarias make a fairy-tale border.

• Strappy New Zealand flax with salmon accents (such as Phormium hybrid 'Maori Maiden') is a great partner for a low-growing blue-flowering rosemary (such as 'Prostratus').