The nine who were charged are Dr Fredrick Mac Palm, Colonel Samuel Kodzo Gameli, Geshong Akpa, W.O.2 Esther Doku, Lance Corporal Ali Solomon, Lance Corporal Albert Baba Ibrahim, Lance Corporal Sylvester Akapewon, Bright Alan Debrah and Corporal Seidu Abubakar.
The charge sheet reads: "Conspiracy to comity treason felony.
2. Treason felony.
3. Possession of explosives, firearms, and ammunition".
The suspects were earlier slapped with five charges.
It includes conspiracy to manufacture arms and ammunition without lawful authority and possession of explosives and firearms without lawful excuse.
Defence lawyer, Victor Adawudu, told Accra-based Starr FM that his clients were expecting to be charged with treason.
He said, "Because of what was put out in the public domain that they wanted to attack the presidency, we expected to be charged with high treason."
Coup plot to destabilise Ghana
The government in a statement released last month said a joint security operation led to the retrieval of several caches of arms, explosive devices, and ammunition from locations in Accra and Kpone-Bawaleshie in Dodowa.
The charge of possession of explosives, arms and ammunition without lawful excuse was then leveled against some of them.
State prosecutor, ASP Sylvester Asare on Wednesday informed the Kaneshie District Court that the serving soldiers were members of 'Take Action Ghana' (TAG), a group led by Dr. Mac-Palm.
According to him, they intended to engage in a series of demonstrations geared at toppling the government.
He revealed they have since secured the services of one other person already in custody to produce explosives and guns for the operation.