Cactus Identification Guide | Most Popular Cacti
Cactus Identification Guide will help you learn about most popular cactus varieties that you can grow at home.
This post may contain affiliate links. Please read our disclaimer for more info.
Cacti can grow in a wide range of environments, including deserts, grasslands, and forests.
Cactus Identification
Cacti are plants of the genus Cactus. They are native to the New World, mainly in South America but with some species in Central America.
Cacti are succulent plants, which are adapted to extremely arid climates. Most cacti live in habitats subject to at least some drought.
Cactus Spines
Cactus spines are almost always hard and sharp, and come in a variety of shapes and sizes. The spines are produced from areoles, which are raised points of tissue on the plant’s stem. The areoles replace leaves as the primary photosynthetic organs in most cacti when they are mature.
Some cacti have no spines, as is the case with C. pectiniferum. The bodies of those cacti are often oddly shaped or colorfully patterned, and have evolved to attract animals that will disperse their seeds.
The spines protect the cactus from animals and absorb sunlight. A spine may be long and needle-like, short and club-shaped, or even reduced to a tiny sharp point. The areoles are the most important structures for a cactus’ survival, because they are responsible for the plant’s water and nutrient gathering.
Cactus stems and leaves
Cacti show a wide range of adaptations to water conservation. Most cacti are succulents, meaning that they have some parts that are more or less water-storing. Their stems and leaves have a relatively large ratio of surface area to volume, allowing them to rapidly take up water from rain or dew. Their roots often have a high density of root hairs. These features are all adaptations to reduce water loss from transpiration, which would otherwise occur rapidly in the hot and dry climate in which most cacti live.
Cactus stems are often ribbed or fluted, which allows them to expand and contract easily for quick water absorption after rain, and then to release that water as soon as temperatures rise again.
The stems of most cacti are also covered with sharp, stiff spines, which discourage animals from eating them. The spines are produced from areoles, which are raised points of tissue on the stems. The areoles replaced leaves as the primary photosynthetic organs in most cacti when they matured.
The stems of most cacti develop spines, which typically remain for the life of the plant. The spines begin as outgrowths of the areoles. The growing tip of the stem, located at the top of the areole, produces a new spine for each areole as the cactus grows.
Areoles generally begin to appear on cacti after they have finished flowering. A spine may begin to grow from an areole as the cactus grows, or it may first appear as a bud and later grow into a spine.
Cactus Care Guide
Cacti can grow in a wide range of environments, including deserts, grasslands, and forests. They are found at altitudes from sea level to over 3,000 meters, and the plants have adapted to a wide range of temperatures, from below freezing to above 40 °C (104 °F).
Most cacti live in habitats subject to at least some drought. They are often found in habitats that receive more rainfall than other deserts, such as deserts with frequent fog and humidity. In these areas, cacti can survive long periods of drought, as their roots can reach water deep in the ground.
Cactus water requirements
Cacti need relatively little water, as long as they are not exposed to prolonged periods of rain and humidity. The stem is often the only part of a cactus plant that requires water.
Most cacti have some way of storing water for later use. In most species, the stem is the part of the plant that holds the most water. The stem may be fleshy, with a large ratio of surface area to volume, or it may be relatively thin and spiny.
When fully hydrated, the seed of a cactus will germinate and grow into a new plant. The new plant produces both roots and leaves, but only leaves are capable of photosynthesis. Therefore, the plant depends on its roots to supply water, nutrients, and oxygen. Cacti are able to survive in the dry climate they live in because their bodies store water. To be able to carry out photosynthesis, cacti have evolved to have highly modified stems, which are capable of storing water and nutrients.
Cactus light requirements
Cacti are native to tropical regions, where they need a lot of sunlight to grow. The spines help the cactus to be able to gather as much sunlight as possible and direct it to their photosynthetic machinery. The spines also help prevent animals from eating the cactus.
