Horticulture - Vegetative Propagation of Plants

Vegetative Propagation

Making more plants without sexual reproduction

Ortet

Original plant where clone plants are made from

Ramets

Clone plants

Clone

A group of genetically identical plants derived from a single individual (ortet), and propagated exclusively from vegetative means (non-sexual)

Advantage and disadvantage of cloning

Limits genetic diversity

Vegetative Propagation Techniques

Cuttings, Layerage, Division, & Grafting

Cuttings

A piece of a plant, made up of one or more organs

• Cuttings are alive

Most home gardeners use

cuttings

What is needed to successfully “root” plants?

• Media (soil)

• Light (Northern exposure)

• Warmth (“Bottom heat”)

• High relative humidity (reduces transpiration)

• Health of the “Mother” - Ortet

Play a major role in future success of cuttings and growth

Light & Plant nutrition

“Sticking” Cuttings

Stick in trays or “direct stick” in containers

Cutting Propagation

• Herbaceous Cuttings

• Softwood Cuttings

• Semi-Hardwood Cuttings

• Hardwood Cuttings

Herbaceous Cuttings

From non-woody herbaceous plants

Softwood Cuttings

Soft, succulent new growth of woody plants, growth snaps when bent

Semi-Hardwood

Partially mature wood of current season’s growth often taken in July-September (may broadleaf evergreens)

Hardwood Cuttings

Dormant mature woody stems taken in late fall, winter, and early spring

Layerage

Stimulate rooting on a stem before the piece is cut from the “parent” (ortet) plant

Types of layering

Ground layering and air layering

Ground Layering

Pin root to soil with an object (rock, wire, etc.)

• Mid Spring (May-June)

• 1-3 Months

• Ex: Azealias, Hydrangeas

Air Layering

A method of propagating plants by inducing roots to form on a stem while still attached to the parent plant, often performed using a moist medium and a plastic wrap to maintain humidity.

• Mid Spring (May-June)

• 3-4 Months

• Materials: Polyethylene plastic, Sphagnum moss, rooting hormone, knife or pruners, aluminum foil

Division

A method of vegetative propagation where a plant is split into multiple sections, each with roots and shoots, allowing for new plant growth.

• Best done in late fall

• Dig up large clump

• Separate clumps with soil knife

• Pot them up, or plant them immediately

• Post division water is crucial

• No fertilizer until next Spring

Natural Plant Hormone

Auxin

Auxin stimulates

Adventitious rooting

Auxin product names

“Rootone” and “ Hormodin”

May & June are ideal for

Propagation

How to propagate Hardwood cuttings

• Plants must be dormant (December … hard freeze)

• Cut and treat with rooting hormone

• Stick in one gallon of water

• Protected shady location outside