Astrophytum asterias, commonly referred to as the sand dollar cactus is a spineless cactus species native to Mexico and parts of Texas. It is a popular choice among cacti enthusiasts due to its unique and attractive shape that resembles the shape of a sand dollar. This plant has eight ribs covered in dense white fuzz and can reach up to six inches in height and eight inches wide when fully grown.
So, what do you need to know about the sand dollar cactus? The cactus belongs to family Cactaceae, subfamily cactoideae, tribe cacteae, and genus astrophytum. The cactus has a dark green stem covered with ribs and woolly areoles. Its stem can grow up to eight inches wide and six inches tall. The plant produces yellow flowers with orange-green centers and small, round fruits that are edible. The fruits are usually covered with dense wooly hairs. The sand dollar cactus thrives in USDA hardiness zones 9a to 11b. The cactus is considered easy to grow. It prefers a warm, sunny location with well-draining soil.
This blog post discusses some interesting facts about the sand dollar cactus that you should know. Read on to learn more.
Sand Dollar Cactus: Overview and Classification
As mentioned earlier, the sand dollar cactus, or Astrophytum asterias, is a spineless cactus species native to Mexico and parts of Texas. It belongs to family Cactaceae, subfamily Cactoideae, tribe Cacteae, and genus Astrophytum.
Its disc-shaped body is divided into 7-10 distinct sections known as ribs. The middle of each rib contains woolly areoles. The areoles give rise to spines and glochids, the primary means of self-defense for the sand dollar cactus.
The sand dollar cactus produces yellow flowers with orange-green centers along with small, round fruits that are edible when ripe. The green stems of this cacti are covered with dense white hairs.
Sometimes, the body may appear speckled since it is covered with white scales known as trichomes. Perhaps, the most important distinguishing feature of this cactus is its resemblance to a sand dollar.
Sand Dollar Cactus: Biology
The sand dollar cactus usually reproduces asexually through cross-pollination. The cactus reaches sexual maturity after two or three years (once they attain about three centimeters in diameter).
The cactus flowers between March and June, and fruiting occurs from late April to June. During this time, small, round fruits are produced, which are edible when ripe.
This cactus is considered a slow-growing species since it may take up to three years for it to reach its mature size of six inches tall and eight inches wide.
The succulent bears a close resemblance to Euphorbia obesa, even though the two are unrelated. In fact, Euphorbia Obesa isn’t even a cactus.
Sand Dollar Cactus: Distribution and Habitat
The cactus is native to parts of Texas in the U.S. and the states of Tamaulipas and Nuevo Leon in Mexico. They mainly occupy the parts to the east of the famous Sierra Madre Oriental Mountain ranges.
Although the sand dollar cactus was previously available in abundance in this region, it has become increasingly rare due to habitat destruction.
Today, the succulent is restricted to a very small part of Starr County in Texas and a few parts in Tamaulipas. Most of it is associated with thorn scrub in rocky grounds that were previously flat and fertile grasslands.
Sand Dollar Cactus: Cultivation
This cactus has mainly been grown as a houseplant since the 1950s. It is a relatively easy-to-grow species that thrive in warm, sunny locations with well-draining soil.
It outshines other members of its genus despite its rarity. The cactus is usually propagated from seed.
Most of the young plants you will come across in nurseries are seed grown. The popularity of the cactus among gardeners and collectors has ensured that the species remains available in the market.
Furthermore, it has given rise to several cultivars. One of the most famous sand dollar cactus cultivars is the Super Kabuto.
This plant resembles the sand dollar cactus, although it has relatively large trichomes that congregate in dense spots arranged in a highly striking and exciting pattern.
The other common cultivar is the Hoshinoko. This one has smaller and more densely packed trichomes.
It also grows faster than the regular plant, making it a handy choice for gardeners who want to see quick results.
Sand Dollar Cactus: Growth Rate
As mentioned earlier, the sand dollar cactus is a slow-growing species. It may take up to three years for the succulent to reach its mature size.
It is important to provide enough light for the plant for it to thrive properly. The cactus does not require frequent watering and can be watered only when the soil is dry.
Generally, this cactus species is not prone to disease or pests and can do well in favorable indoor conditions. With the right care, it can live for many years in your home.
Sand Dollar Cactus: Care and Maintenance
Typically, the sand dollar cactus prefers a warm, sunny location with well-draining soil. Water it moderately during spring/summer months and keep it dry during winter. The temperature should remain between 10-25 degrees Celsius to ensure proper growth.
Maintain the humidity levels at about 40-50%, as this is the optimal range for the cactus’ growth. Too much humidity can encourage fungal diseases.
The cactus should be fed with a balanced fertilizer once every two or three months to ensure proper growth. To prevent any nutrient deficiencies, it is important to use fertilizer specifically meant for cacti and succulents.
It can also be grown outdoors, although this cactus species is mostly viewed as an indoor plant due to its slow growth rate and spectacular appearance.
Depending on its size, it is important to repot the sand dollar cactus every spring or once in two years. Don’t forget to remove dead leaves and stems before repotting.
The cactus should be pruned regularly to maintain its shape and size and promote the healthy growth of the plant. It is also important to check for pests or diseases from time to time and take appropriate action if needed.
Ensure the soil remains slightly acidic or neutral and use a fertilizer rich in potassium and nitrogen.
Finally, you must be careful when handling the cactus because its spines can cause skin irritation. When it comes to maintenance, regular pruning may be necessary depending on the state of your plant.
Sand Dollar Cactus: Flowering
This cactus usually flowers during summer or spring. The flowers are small, white, and bell-shaped with yellow stamens and light green sepals. They may be solitary or in clusters, lasting only a few days.
Once the cactus is mature enough, it will produce many flowers before going dormant during winter. Consider leaving the flowers in place because they will eventually die on their own.
Sand Dollar Cactus: Toxicity
The sand dollar cactus is not toxic to humans or pets. However, it is important to be careful when handling the plant because its spines can cause skin irritation.
Keep it away from children and pets to prevent accidental ingestion and be sure to seek medical help in case of ingestion.
Its fruit is edible, but you need to prepare it properly before consumption. The seeds of the cactus may also be used for propagation.
To prepare the fruit, remove the spines and cut it into small pieces before cooking. The cooked fruit can be eaten as is or added to other dishes such as salads.
Sand Dollar Cactus: Propagation
The sand dollar cactus can be propagated by seed germination or stem cuttings. If propagating by seed, sow them in small pots with well-draining soil mix and cover them lightly with sand.
Keep the soil moist but not wet and place the pot in a warm location where sunlight is available. The seedlings will take about two to three weeks to germinate.
For stem cuttings, you can use a sharp knife or scissors to carefully remove the stems from the mother plant. Allow the cuttings to dry for a few days before planting them in pots filled with well-draining soil mix.
Keep the soil moist but not wet and place the pot in a warm location with plenty of indirect sunlight. The cuttings may take several weeks to root.
Sand Dollar Cactus: Conservation
The cactus is listed as an endangered species in some parts of the world and is thus protected by law.
To prevent its extinction, it is important to take measures such as propagating it sustainably, avoiding habitat destruction, and using only legal sources when buying or selling this cactus.
It is also essential to avoid over-harvesting its fruit and seeds, which can reduce its population. Taking these steps can ensure that this unique and beautiful cactus remains in our environment for many years.
Final Thoughts
The sand dollar cactus is a unique plant that adds beauty and character to any indoor or outdoor garden.
It requires minimal effort to maintain and is ideal for novice gardeners who want something easy to care for and interesting to look at.
With its slow growth rate, a striking pattern, and unusual flowers, this cactus is definitely worth adding to your collection.
Last update on 2023-02-03 / Affiliate links / Images from Amazon Product Advertising API
