Mammillaria pacifica

AKA Mammillaria petrophila ssp. baxteriana

Mammillaria duwei

Water in summer.  Allow soil to dry between watering.  Place in deep pot to accommodate tap root.  Well draining soil. Keep dry in winter.  Feed with a high potassium fertilizer in summer.  Frost resistant if kept dry.  Full sun or afternoon shade.  Indoors, needs bright light and some direct sun. 

Mammillaria camptotricha

A beautifully spined Mammillaria!  I was fortunate to have this offset after killing the
mother plant which died of rot.  Too wet in winter!

Mammillaria spinosissima

Summer grower
Keep dry in winter
Water sparingly in summer

Mammillaria vetula ssp fracilis var "Arizona Snowcap"

Winter dry
Water sparingly in summer

Mammillaria saboae handeana

Summer grower
Keep dry in winter
Likes small dose of potassium in summer

Mammillaria geminispina

Mammillaria herrerae

Mammillaria hernandezii

Newly purchased

Two years later