(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
This gorgeous plant is known for its vertical ribs along the side of rib. The name astrophytum means start plant, because of its start like shape. As the cactus ages the ribs becomes more prominent and it also gets more into a cylindrical shape. It grows up to 70-100 cm tall and 10-20 cm in diameter.
Recommended temperature zone: USDA: 9b-10
Frost tolerance: Hardy to 20° F (-6°C)
Sun exposure: Light shade
Origin: Mexico (Querétaro, Hidalgo)
Watering Needs: Moderate water in summer. Allow the soil to dry before watering again. Do not water in winter.
Propagation: Seeds that germinate rapidly.
Blooming habits: The Astrophytum ornatum blooms in summer. The 2.5" wide flowers (6 cm) are pale yellow and scented. It needs to be 6" tall to bloom (15 cm). This might take six years or more depending on the length of its growing period in your local conditions.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz