I really don't know since I am not a gardner but I have surfaced the internet for any reason "why does my rose bush have no flowers". Listed below are possibilities.
Have you been pruning it? The buds will grow on this year's growth so it is possible that if you pruned it too late you have got rid of the forming buds. Pruning is best done after flowering but not if frost is likely - in that case leave it until early to mid spring.
Roses are very sturdy though so it is more than likely that it will be putting on more growth at the moment and will try to flower from that a little later in the season.
Give it a good feed (Rose feed encourage flower growth - so that will help too)
Here are some of the reasons that roses don't bloom.
1-The rose plant is not getting enough sun. Roses need at least 6 hours of direct sun a day to perform well.
2-The rose needs more water. Roses like at least an inch of water per week during the growing season.
3-The plant has been given too much fertilizer, especially Nitrogen. Too much fertilizer can either damage the plant or cause it to grow extra leaves and stems at the expense of blooms.
4-The rose is a new plant. Don't expect too much from a plant during its first year.
5-Rose is a once blooming variety. This means it will bloom only once a year in the late spring or early summer.
6-Soil pH is too low or too high. If the pH is not in the range of 6.0 to 6.8 (ideally 6.5) then nutrient uptake will be reduced, and the plant won't be getting the food it needs to produce flowers.
7-Not enough foliage. If the bush doesn't have adequate foliage, it can't produce the food it needs to make new flowers. Inadequate foliage may result from disease or too little fertilizer