I planted all my pea's but I did it without even thinking of how tall they would climb.
You didn't say what kind of peas...green english type peas only a few feet...but summer climbers like pink eye can climp 6 feet easy.
Even English peas come in assorted sizes. There are cultivars which only get 12 to 18 inches, others run 2-3 ft, there are cultivars like Telephone and Burpees Sugar Snap that will push 6 feet. Many southern peas can be quite viney, but there are few with fairly compact vines ( under 2 ft). You will need to know not only type but cultivar(variety).