Which incense should be offered to the navagraha individually for graha shanti?
I think Surya likes the smell of lotus flowers, but I have no idea what smells the other grahas like.
Does someone know?
The procedure of worship of Navagrahas is mentioned in the Padma Purana Srishti Khanda Chapter 61, 82. It was said by Vyasa to Vaishampayana and other disciples. The incense and the colours they like are also mentioned along with the procedure of worship to individual planets.
Surya - Hibiscus (Japa flower), Indian Oleander (Karavira), red saffron flowers of spring. Arka leaves (Calotropis gigantea).
Chandra - White fragrant flowers and garlands.
Kuja - As, Kuja or Mangala is Lohitanga, red flowers and anointments are offered to please him.
Budha - Sandal, incense of fragrant flowers.
Guru - Yellow coloured fragrant flowers.
Shukra - With white sandal, white flowers.
Shanaishchara - with black sandal, black flowers, pieces of cloth of that kind (i.e. of black colour), oil and sesamum.
Rahu - Flowers and objects same as Shanaishchara.
Ketu - The objects that are same as Shanaishchara.
Each graha has its own incense as same as the Flowers mentioned in the above answer.
Planet - Incense(Dhoopam)
Sun - Sandal
Moon - Benzoin
Mars - Goggul
Mercury - Pure Camphor
Jupiter - Lotus/Lily petals
Venus - Clove
Saturn - Black wood
Rahu - Mustard
Ketu - Red wood
Using the above dhoopams on corresponding days or offering in homam brings a good result to physical and mental health.