What zone are you in?

I am in central NJ, I think it's zone 6. If not 6, then 7.

Did you have a cooler spring this year?

Possibly it is a Late Large Flowering Type 3 and the earlier ones are Type 2, Early Large Flowering.

Or maybe it is just being lazy. You could try pinching off some of the growing tips to see if this would wake it up. Since it is not blooming, feeding again wouldn't hurt, also mulch with dried cow manure, but not near the stems.

Is the clem several years old? Younger ones sometimes have their own time schedule.

Marie

Marie is correct..being in a colder zone you are behind alot of us so they could be ready to start setting it's flowerbuds soon!!..Also make sure you aren't using a fertilizer that has a high middle number (N) Nitrogen as it will make the plant produce gorgeous green leaves but inhibit blooms....Jeanne

Isn't N the first number? NPK? I think you would want a high middle number.

Sowwy...I meant in the NPK ratio...Make sure the FIRST number isn't the highest as that is Nitrogen and will produce the green leaves and inhibit blooming..you want the P (the middle number) to be highest to encourage the production of blooms...thanks Mehearty...Jeanne