Is there some sort of magic trick for climbing roses!?

There are many variables that will have and effect on the growth of your climbing roses. I grew a climbing rose at my old house which only managed around a foot per year (on good years!). I can only suggest that you make sure that the roses are well fed and watered. As with most aspects of gardening, you can only do your best to provide the best conditions possible, then it's up to the plant! It will take time for the plants to 'settle in' before they start to noticably grow anyway, so just keep an eye on it, tie new growth to the arch and be careful of the thorns! lol.

Good luck with it, I'm sure it will look gorgeous within a few years.

Are they in full sun? You don't want roses in the shade.

I see a lot of people do things you shouldn't with plants. Then they ask me why they died. I feel like answering because you didn't ask me before you planted it. LOL

Feed your roses weekly with a diluted solution in the spring through early summer. If the fertilizer says to fertilize every 2 weeks. Make it half as strong and use it every week.

Would a baby grow faster if it ate 1 big meal every 2 days or several small meals every day?