Dendrobium nobile type orchids have flowers along the length of the upright canes.
To re-flower these plants is is necessary to try to mimic the monsoon conditions of the Himalayan foothills!
Let the current canes mature for a month after they have produced their terminal leaf and the end of the cane goes rounder; do not give any fertiliser during this time.
For the next 5 weeks keep at night temperatures of 10C or less, keep dry and in good light.
Then back to normal intermediate temps 13-15C for 7 weeks, and in that time buds will form. Once the buds are definitely flowers give some water; water too soon and keikeis (plantlets) may form instead of flowers.
No fertiliser until the new canes start growing, early March onwards. Water freely during the summer.