Casual gardeners who've inherited a garden or borders when they've bought a new house or adopted one in a community program might be taken aback at the challenge of identifying flowers in their new garden. Most plants, though, will help out by providing clues in their habit of growth and inflorescence (flowers). The earlier in the year you can get started the better. Your first hint is that most plants that come up without help from you are perennials or biennials.
Make a scale drawing of your garden and mark each plant's location. Number each plant. Make a chart listing plants that you think are the same variety (or cultivar) because they look identical and broke the surface at the same time.
Take notes on the plant's growth habit. Plants might grow in a single stalk or branch. Their leaves might be oval or grass-like with veins that are parallel or may radiate from the stem. All flowers in the lily family (Liliaceae) grow from bulbs, tubers or corms and those from the mint family (Lamiaceae) have square stems.
Count the petals and stamens and look for bracts in the flower (inflorescence). Members of the aster family (Asteraceae) like daisies, sunflowers, zinnias and marigolds have petals in multiples of five but the real flowers are the hundreds of florets or bracts in the center of the inflorescence, each with its own reproductive organs. Lilies have no bracts but have petals in multiples of three, six stamens and one prominent pistil.
Note when the flower blooms. Most perennials bloom at specific times; roses and peonies in early summer, lilies, dahlias and daylilies throughout the summer and asters and chrysanthemums in the fall. Although breeders have extended the season of bloom for many flowers, their most vigorous showing will be during their natural bloom time.
Combine the habit of growth, manner of inflorescence and period of bloom to look for a match. Since many flowers come in every color of the rainbow, color will be helpful only for native wildflowers like the delicate buttercups and trilliums that grow around the uncultivated borders of abandoned gardens in woodsy areas.