Escobaria alversonii is in my opinion the most beautiful of all Escobarias. It is slow but becomes large given enough time. Dense while spines with dark tips are very decorative. Flowers are light-pink and come up in June in the wild.
The picture is taken in Joshua Tree NP. E. alversonii is a common plant there, if looking at right location. It occurs on the slops or near the rock outcrops.
In the culture Escobaria alversonii is somewhat difficult plant. As many Mojave desert cacti and only one another Escobaria it is not much tolerant to summer watering, and a bit slow from seed. Flowering specimens a rarely seen in collections.