For starters, when thinking of combinations, be sure to consider more than a plant's color or leaf size. Remember that the garden exists through the seasons and over time. Plants are changeable, and grow at different paces. The plants you choose to share the same few inches of ground need to be as harmonious in spring as in autumn, and not grow so vigorously that they squeeze or shade out the others. Remember, too, that many ideal combos never even show themselves at the same time. Early tulips and hostas can exist in the same small patch of ground; the tulips bloom first, dying back to allow the hosta leaves to emerge and cover up the bulb's withering foliage. Lilacs bloom in May, then serve as a green scaffold for a summer-blooming clematis.

But the real drama comes when you ally two or more plants whose foliage and flower play off each other to emphasize both to the best advantage.

Now In Bloom Red hot pokers are long-blooming and attractive to bees, and come in a wide variety of colors besides the plain, old-fashioned orange. They need a sunny location, moisture in the spring when budding up, and well-drained winter soil. Kniphofia 'Green Jade' grows to 5 feet, its flower spikes starting out green and fading to cream and then white by late summer. K. 'Ice Queen' is pale primrose yellow, and K. 'Bees' Sunset' (above) is a little shorter with flowers in rich apricot.

Arranging flowers has taught me more than anything else about effective plant combos because that is when I look closely enough to isolate the essential elements. I've picked chocolate cosmos to combine with a branch of Rosa mutabilis, realizing only when I see them in the vase that it'd be a good idea to move the cosmos in front of the rose. I planted another bunch of buff-colored lilies when I realized they were the same soft shade as the Rosa 'Penelope' blooming on the other side of the house. I probably never would have figured it out if I hadn't gone looking for flowers to complement the rich tones of a coppery vase.

A reward for being a lazy gardener is that self-sown seedlings are often left alone long enough for Mother Nature to form her own beguiling patterns. Right now I have some willowy purple Verbena bonariensis sticking up between the branches of a yellow variegated shrubby dogwood. If I'd weeded too quickly (little chance of that), I never would have discovered how happily the two coexist, playing off each other in both form and color. Earlier in the season, the dogwood's stiff arms embraced floppy peonies. For those of us inexpert at staking, using plants to support each other eliminates that stiff, tortured look as well as the trouble of tying up plants.

Seeing plant groups in three dimensions, and as part of a larger composition, is always more helpful than looking at photos for ideas. The perennial border at the Bellevue Botanical Garden is filled with inspiring combinations, as are display gardens at nurseries.

While plants paired by color may be the most dramatic, sometimes the eye tires of theatrics. Subtler combos based on leaf texture or shape can be the most satisfying. Right now I'm enjoying huge rough gunnera leaves mingling with the fluffy form and white flowers of mock orange, set off by the white-rimmed spikes of Scrophularia auriculata 'Variegata.'

In my shady side garden, filling in below slightly pruned-up hydrangeas, is an overlapping pattern of crinkly-leafed, dark purple-green ajuga and the glowing chartreuse of Lamium maculatum 'Aureum.' A spreading Styrax japonica shelters the hydrangeas, its little white bells shown off by the similarly shaped, although larger, flowers of purple Clematis alpina.

This game of combining can be played at all levels, from carpeting plants to overstory layers. I'd love to hear what combinations you've most enjoyed in your own garden and what it is you find special about them. If you'll e-mail me one or two of your favorites, I'll include them in a future column, and we'll compare notes.

Valerie Easton is manager at the Miller Horticultural Library. Her book, "Plant Life: Growing a Garden in the Pacific Northwest" (Sasquatch Books, 2002) is an updated selection of her magazine columns. Her e-mail address is vjeaston@aol.com.