Blackman began her career as a street musician in New York City. She studied three semesters at Berklee College of Music in Boston and was a student of Alan Dawson. She returned in the 1980s to New York, where she runs her own band (including with bassist Kim Clarke). She is best known as the drummer of the rock singer Lenny Kravitz, with whom she worked from 1993 to 2004.
In addition, she has performed with musicians such as Jackie McLean, Joe Henderson, Don Pullen, Hugh Masekela, Pharaoh Sanders, Sam Rivers, Cassandra Wilson, Angela Bofill, Bill Laswell and Buckethead. She released eight solo albums and the instructional video Multiplicity took in 1997. In spring 2009, Blackman toured with Socialibrium through Europe (including with Bernie Worrell and TM Stevens).
Blackman attended a Baptist church in her youth, but was at the age of 18 years a follower of the Baha'i faith and in the 2000s she began a study of Kabbalah. On July 9, 2010 Blackman and Carlos Santana announced during a concert of his Universal Tone Tour in Chicago to get married soon. The wedding took place on Maui on December 21.
- Code Red with Steve Coleman, Wallace Roney, Kenny Barron, Lonnie Plaxico, 1992
- Arcane with Wallace Roney, Joe Henderson, Kenny Garrett, Larry Willis, Buster Williams, Clarence Seay, 1992
- Telepathy with Antoine Roney, Jacky Terrasson, Clarence Seay, 1994
- The Oracle with Gary Bartz, Kenny Barron, Ron Carter, 1996
- In the Now with Ravi Coltrane, Jacky Terrasson, Ron Carter, 1998
- Works on Canvas with JD Allen III, Carlton Holmes, George Mitchell, 1999
- A Lil 'Somethin ' Somethin ' with Kenny Barron, Gary Bartz, Ron Carter, Kenny Garrett, Lonnie Plaxico, Wallace Roney, Clarence Seay, Jacky Terrasson, Buster Williams, 2000
- Someday ... with JD Allen III, Carlton Holmes, George Mitchell, 2001
- Music for the New Millennium with JD Allen III, Carlton Holmes, George Mitchell, 2004