Rooting systems

Before you start experimenting with propagation, it’s also helpful to understand what roots are and why they’re so important. 

Plants, like humans, have specialized organs that help them survive and reproduce in a variety of habitats. The major organs of a plant include the roots, stems, and leaves. They are found almost entirely underground and perform a range of services that are essential to the survival of a plant.

Roots perform the following functions:

• Help plants anchor themselves into the ground
• Absorb oxygen, water and nutrients from the soil for the plant
• Store energy produced by photosynthesis
• Resist forces from wind, water and mud flow that could damage the plant
• Support the microorganisms in the soil that benefit plant life

Plant roots are also extremely beneficial to human’s way of life. They prevent soil erosion, serve as a source of food (such as carrots, turnips and beets) and assist in the rehabilitation of depleted soils for future crop production. 

Types of rooting systems:

There are two main types of rooting systems that a plant can have: a fibrous rooting system or a tap rooting system. 

Fibrous root systems, common in monocots, have many extremely thin roots that spread out under the surface and form a ‘mat’ of roots underground. Because their roots are close to the surface, these systems may be fragile and unstable. However, they grow quite extensively and provide excellent exposure to nutrients and water in the soil as it covers a large surface area.

The tap root system occurs when a plant has a main root (the “tap root”) that delves deep into the soil with multiple lateral roots growing out from it. By having a thick tap root that grows deep into the soil, the plant gains extra anchorage to the ground and food storage. This system is found in many dicot plants.

It is common knowledge that roots grow below ground, but in certain cases, they will grow above ground from the stems and aves. Plant roots such as these are labelled adventitious/aerial roots, a term used to describe a structure that grows in a strange place.

Water roots versus soil roots:

Plants are truly amazing because they can grow roots in both soil and water. There are, however, some key distinctions between the roots that develop in each environment.

• When propagating in water, the roots that develop are fragile, thin and white with many root hairs. They require less energy because they can ‘breathe’ in water and have easy access to water and nutrients. 

These roots are beneficial in the beginning, but over time, plant growth plateaus in water and this is why cuttings should be moved over to soil. 

• Once cuttings are propagated or planted into soil, the roots change to adapt to their new environment. They become dark, thick and sturdy as they grow in the ground in search of nutrients. They require more energy to grow. They also don’t have the ability to ‘breathe’ underwater and become more susceptible to root rot.

The majority of nutrient uptake occurs near the tip of a plant’s roots. Here, very fine roots called root hairs develop. These root hairs have a large surface-area-to-volume ratio. This improves the efficiency of water and mineral absorption. These root hairs save the plant time and energy!