Observing flowers in my garden is the reward for planting and weeding the plot. I take joy in making time to watch sunflowers follow the sun as it moves overhead; the process is so gradual that I marvel at incremental shifts. I delight in daylilies opening in the morning and closing in the evening. These prolific flowers are glorious one day and then fade. The morning glories are heavenly blue as day breaks and close up tight when the sun in overhead.

You don't have to have a sundial in your garden to follow a day's arc. Carl von Linne (also known as Linnaeus) just planted flowers to tell the time of day. By watching for the opening and closing of the blossoms, he claimed "nature's clock" was accurate to within a half an hour on a sunny day.

Here are some plants that can help you tell time:

Be sure to plant some flowers that welcome the dark. You might even see nocturnal moths pollinate these fragrant plants, much as bees and butterflies do with plants that bloom during daylight hours. The moonflower is the night-blooming relative of the morning glory. It vines on my garden fence and its saucer-like white blossoms look like the horn of an old phonograph. Datura is also a wonderful night plant. Its greenery frames the large white trumpets that lure night's insects.

What fun it is to see how your backyard can be both an indictor of the time of day and a reflection of each season's phases.