Herbaceous Ornamental Plants Morphology Notes

Herbaceous Ornamental Plants Morphology Overview

General Lab Instructions

• Objective: Utilize the Leaf & Flower Terminology Manual (LFTM) to examine and identify plant morphology based on distinct categories.
• Examine Plant Samples: Focus on leaf arrangement, margin, shape, tip, base; flower, and inflorescence type.
• Draw Plants: Illustrate each plant and include detailed descriptions of parts such as leaf shape, arrangement, and flower or inflorescence type.
• Submission: Compile findings into an ID file for submission to the teaching assistant.

Plant Samples to be Studied

• Pelargonium x hortorum (Zonal Geranium)
• Pelargonium x domesticum (Regal Geranium)
• Pelargonium peltatum (Ivy Geranium)
• Pelargonium grandiflorum (Big Flower Geranium)
• Pelargonium graveolens (Rose-Scented Geranium)
• Dianthus barbatus (Sweet William)
• Dianthus chinensis (Annual Pink)
• Dianthus chinensis x barbatus (Hybrid Pink)
• Dianthus caryophyllus (Cut flower carnation)
• Lobelia erinus (Bedding Lobelia)
• Bellis perennis (English Daisy)
• Gazania rigens (Treasure Flower)
• Gerbera jamesonii (Transvaal Daisy)
• Calendula officinalis (Pot Marigold)

Detailed Plant Morphology Overview

Pelargonium x hortorum

• Leaves:
  • Shape: Orbicular to kidney-shaped
  • Margin: Lobed with a horseshoe-shaped darker zone (zonation)
  • Arrangement: Alternate
• Flower/Inflorescence:
  • Type: Umbels with 5 petals, often semi-double or double due to transformed stamens.

Pelargonium x domesticum

• Leaves:
  • Shape: Cordate to kidney-shaped, approx. 6 cm wide
  • Margin: Sharp unequal teeth
  • Arrangement: Alternate
• Flowers:
  • Type: Showy and held in umbels.

Pelargonium peltatum

• Leaves:
  • Shape: Ivy-shaped, leathery, circular zone, 5 triangular lobes
  • Arrangement: Alternating
• Flowers:
  • Type: Held in umbels of 3 to 9 flowers.

Pelargonium grandiflorum

• Similar to P. hortorum in structure and morphology.

Pelargonium graveolens

• Leaves:
  • Size: 3 to 5 cm wide, gray-green, deeply pinnately cut
  • Arrangement: Alternate
• Flowers:
  • Type: Pale pink, held in umbels (4 to 5 florets).

Dianthus barbatus

• Leaves:
  • Shape: Lanceolate, 5 to 7 cm long, opposite with a prominent midrib
• Flowers:
  • Characteristics: Toothed/fringed petals, distinct eye, arranged in flat-topped cymes.

Dianthus chinensis

• Leaves:
  • Shape: Opposite, slightly hairy, lanceolate
• Flowers:
  • Fragrant, 10 to 15 flowered cymes with deeply cut petals.

Lobelia erinus

• Leaves:
  • Lower: Toothed, ovate, short petioles; Stem: Linear, almost sessile
• Flowers:
  • Color: Blue to violet, in spikes, with exerted stamens.

Bellis perennis

• Leaves:
  • Shape: Oblanceolate to spathe-shaped, basal rosettes
• Flowers:
  • Small florets held in heads, less than 2 cm wide.

Gazania rigens

• Leaves:
  • Basal: Long and spatulate; Upper: Divided in growth rosette
• Flowers:
  • Borne on smooth peduncles with a dark ring of ray florets.

Gerbera jamesonii

• Leaves:
  • Structure: Entire, dentate/lobed, in rosettes
• Flowers:
  • Structure: Semi-double in head type inflorescence.

Calendula officinalis

• Leaves:
  • Arrangement: Alternate, simple oblong; hairy
• Flowers:
  • Size: Up to 8 cm wide, in dense head type inflorescence (ray & disk florets).

Terminology Reference

Leaf Arrangement

• Types:
  • Opposite, Alternate, Whorled.

Leaf Structure

• Simple vs. Compound:
  • Palmate, Even-Pinnate, Odd-Pinnate, Ternate, Tri-Ternate.

Flower Parts

• Stamen (Anther + Filament)
• Pistil (Stigma + Style + Ovary)
• Perianth (Calyx + Corolla)

Inflorescence Types

• Actinomorphic: Symmetric flowers. Examples: Raceme, Spike, Umbel, Corymb.
• Zygomorphic: Asymmetric flowers. Example: Cymes, Heads.

Leaf Margins

• Types: Entire, Serrate, Lobed, Cleft, etc.

Leaf Shapes

• Examples: Cordate, Lanceolate, Oblanceolate, Linear, etc.

Leaf Apex and Base Types

• Apex: Acute, Acuminate, Cuspidate.
• Base: Cordate, Rounded, Cuneate, etc.