My first thought would be not enough sun.......

Sometimes they just need longer to develop a good root system--so that they can bloom easily. My neighbor has been waiting 5 years for her hydrangea to bloom. Finally, this year (its 5th) it bloomed. She was amazed.

Kate

Assuming you are talking about a Macrophylla, splitting and potting in the Fall are stressful and may have caused the plant to abort the flower buds. Think transplant shock. Not enough moisture in the potting mix may have had similar outcomes (aborting the flower buds) too. But it is good to know that they appear to be healthy!

I would not worry about lack of blooms much on year one but I would keep an eye on this in future years. Keep an eye on soil moisture and remember to fertilize them more often than you would a hydrangea planted on the ground.

Thanks for the input. I have been feeding them, and keep the soil moist without overwatering. The leaves look very lush and healthy, so I will be patient and hopefully next year will enjoy blooms.