Most plants reproduce naturally without the involvement of human beings.
They do so by natural methods using stems, roots, and leaves.
Roots:
Tuberous roots of Dahlia, sweet potato, and Asparagus can be set aside for multiplication in the next season.
Dahlia
Sweet potato
Stems:
Stems are the most common part for vegetative propagation.
Oxalis
Plants such as Oxalis and grass grow horizontal stems parallel to the ground, almost touching it.
New roots sprout from the nodes (slightly swollen areas occurring at regular intervals on a stem or branch).
New shoots also grow upwards forming new plants at frequent intervals.
Chrysanthemum
In plants such as mint and Chrysanthemum, horizontal stems arise from the base of the erect shoot, grow horizontally in the soil, and then come out to form new aerial shoots.
These shoots become independent plants when stems break away from the parent plants.
Vallisneria
Wild strawberry
Some plants have arched stems which cross over small obstacles and develop small plantlets at their nodes, e.g., Vallisneria, wild strawberry.
Some plants have stems which grow underground.
They are mostly swollen because they have food stored in them. This food is used by the new plants to grow.
The different types of underground stem are: rhizomes, bulbs, tubers, and corms.
Rhizome of ginger
Rhizomes have buds from which outgrowths are produced which give rise to new plants.
This is seen in ginger, turmeric, and banana.
Onion bulb
Bulbs can be considered to be very short underground stems encased in thickened fleshy bulb scales (which are modified leaves).
The scales serve as sites of food accumulation.
In the spring when a new plant shoots up from the centre of the scale cluster, it will draw its food from the scales.
Tuber of potato
Tubers have buds in the eyes, which give rise to new plants, e.g., potato.
Corm of gladiolus
Corms are lots of rhizomes joined together which develop into new plants, e.g., Gladiolus and Colocasia.
Colocasia
Leaves:
Leaves of a number of plants, such as Bryophyllum, develop small buds called adventitious buds on their margin.
