Rhizomes: definition and examples of plants

The stem that grows below the ground and horizontally is called a rhizome , so that it is considered an underground stem like bulbs and tubers, being capable of storing nutrients, therefore, they function as reserve organs for the plant when it faces extreme conditions or nutrient shortage. Furthermore, by growing horizontally it can also support the plant.

Plants that have this type of stem are usually perennial, so while they lose their leaves and surface parts during the colder months, they continue to preserve the rhizomes and store the nutrients that the plant needs to survive. This ability makes rhizomes very interesting stems for human use and consumption, such as ginger, valued for its properties and used both for consumption and for the treatment of certain ailments.

The rhizomes can grow and cover large areas of the ground, since their growth is indefinite . With the passage of time and the increase in length of the rhizome, the oldest parts can die. In these cases, if the shoots of what, at first, was the same plant are separated by a dead zone and therefore, two different plants will be considered.

This means that the reproduction of the rhizomes is asexual . From a fragment (as long as it has a bud) of the rhizome, shoots, roots and new plants can emerge . Therefore, in gardening the transplant technique is applied to promote its reproduction and growth. Once the rhizome has been transplanted, it will use the stored nutrients for the development of the new individual. For this reason, its division and planting usually take place during the months that present more favorable conditions, such as the beginning of spring, summer and even during autumn.

Depending on the type of branching and growth that the rhizomes present, they can be divided into two different types :

• Defined or sypoidal rhizomes: their growth is defined, which implies that the original plant can die when others appear too close to it. The symploidal rhizomes usually have short and thick nodes, being in turn, capable of storing a large amount of nutrients.
• Undefined or monopodial rhizome: its growth is considered indefinite, since the original plant never dies, giving rise to a large number of new plants. It is characterized because its nodes are more elongated than those of the defined rhizomes and new nodes and rhizomes are continuously generated.

As we have said before, plants that reproduce by rhizomes are perennial, here are some examples:

• Ginger : it is one of the most popular plants with rhizomes, belonging to the Zingiberaceae family, due to its multiple uses and properties.
• Grass: or white grass. It has a thin and elongated rhizome.
• Caña de las Indias: it is a plant of tropical origin and, despite having rhizomes, which favor its development and growth, it needs a lot of attention and care for its maintenance and conservation.
• Mint: it is one of the plants that have the most valued rhizomes, like ginger, for its properties, smell and peculiar flavor.
• Lily: it is one of the plants with rhizomes that have thick and leafy stems, which allows them to survive extreme temperatures and harsh winters.
• Solomon’s Seal: characterized by the presence of white tubular flowers. For its growth and development it requires a large supply of nutrients, so the presence of rhizomes favors their absorption, storage and disposal.
• Bamboo: all bamboo species reproduce by rhizomes, having a great interest especially in gardening, in order to create barriers that provide us with separation, protection or greater privacy in our homes.