Plant Identification Secrets: Using Keys, Images, and Expert Help

Identifying an unknown plant is a matter of knowing a little biology and doing a lot of observation. A magnifying glass helps examine details of flowers (and parts), fruits, leaves, seedpods, cones.

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• Flowers (and all their parts)
• Fruits
• Leaves
• Seedpods
• Cones

Using Plant Identification Keys

Keying is the process, especially starting from scratch. Online plant ID keys quickly identify plants but usually focus on a specific region or plant type (weeds, trees).

Some keys are dichotomous—divided into two parts. Start with two choices; each choice leads to next two, until identification (typically 6–9 steps). Others are multichotomous/polyclave—multiple choices per step, fewer steps.

The more details you know, the better. Some characteristics appear only later in the year or at maturity.

Identifying Plants with Images

Looking at pictures of identified plants helps, especially from reliable sources. But beware: plants change across seasons and life cycles.

Ask an Expert

County extension service or university botanists can help. Preserve a sample by pressing flat (not for fruits/berries) or keep briefly in a bag in the fridge until you can show it.

Learn About Plant Families

Botanists group plants into families sharing common characteristics. Learning basics speeds identification. Here are starting points:

Aster family (Asteraceae): Daisy-like flowers. Think sunflower, blanket flower, yarrow, chrysanthemum, osteospermum, marigold.

Mint family (Lamiaceae): Square stems, paired leaves, aromatic foliage. Think mint, sage, rosemary, lamium, Russian sage, coleus, lamb's-ears.

Lily family (Liliaceae): Grow from bulbs; long thin leaves; six petals, six stamens; seed capsule inside flower. Think lilies, dog's-tooth violet, fritillaria, agapanthus, tulip, mondograss, hosta.

Rose family (Rosaceae): Woody stems, large 5-petal flowers, many stamens, simple/compound leaves. Think rose, strawberry, apple, cherry, plum, peach, flowering quince, cotoneaster, firethorn.

Olive family (Oleaceae): Woody stems, showy 4-petal flowers, opposite leaves. Think forsythia, lilac, jasmine, privet, lilac.

Dozens of differences exist within each family (e.g., cultivated roses often have >5 petals). Once you dig into a plant's "family tree," you'll be enchanted by nature's variables. Learning ID tools adds to gardening enjoyment.