Same here... the Cascade is the slowest.
I have Cascade, Mt. Hood, Tettnanger, and Chinook. The Mt. hood it about 18" tall already, and the Cascade is a group of miniature bushes about 3" round and 1" tall.
I planted the same hops while I was up in OR. Due to some neglect and insect damage, they all suffered somewhat. The cascades overgrew all of the others and were a bumper crop for me year after year. They were great plants.
Some varieties of hops will just grow better than others on the west side of the mountains. 30 mins north of Seattle and my Glacier, Willamette and Hallertau are already up to about 6 foot on several bines. My centential is still under a foot high.
Look for hop varieties that can handle wet weather for the west side. The hops that need heat (like centential) will underperform. It almost seems as bittering hops need heat.
My 2nd year nuggets and galena are about 5' already. I have a 6 year old Willamette that is about a foot tall. Added 3 new varieties this year: cascade, centennial, and zeus. All are just starting to poke up few inches. Gotta love the fertile Willamette Valley!
I planted the Chinook and Northern Brewer in miracle grow potting mix. The Cascade was planted in Sta-Green potting mix. The Cascades are about 1/4 the size of the others and have yellow spots on the leaves. This morning I replanted the Cascades in miracle grow. We'll see what happens.