As far as jihad-e-akbar, the jihad of self-reformation, a struggle against one’s own passions, and jihad-e-kabir, struggle in the spread of the Word of God, are concerned, they are incumbent on all Muslims throughout their life.
Regarding jihad-e-asghar, the defensive battle to protect the freedom of worship of God, this is only obligatory on the able bodied adults. See: What does the term “jihad” mean?