January: Month of the Holy Name
February: Month of the Passion
March: Month of St. Joseph
April: Month of the Blessed Sacrament
May: Month of the Blessed Virgin Mary
June: Month of the Most Sacred Heart of Jesus
July: Month of the Precious Blood
August: Month of the Immaculate Heart of Mary
September: Month of the Seven Sorrows
October: Month of the Most Holy Rosary
November: Month of the Holy Souls
December: Month of the Divine Infancy
The months are based on the liturgical feasts which take place on certain days during those months. For example, October is dedicated to the Rosary because the feast of the Rosary falls on October 7th, etc.
Hope this helps.