What's wrong with my hop plant

[MatchstickBrewingCo.]

First time hop grower here and, as you can imagine, I'm worrying about everything. Everything seems to be going ok, the vines are growing up twine a little slower than I imagined but it's going. The only thing I've noticed is that on the bottom leaves on both my plants are starting to brown a little. (see pic if it works). Anybody know what this means? Am I not watering enough? too much? need more fertilizer? bugs? disease?

Thanks in advance for the help!!

 

[day_trippr]

The last time I saw that damage on my plants it was two-spotted spider mites.
Flip the leaves over and check for tiny spider mites and their very fine webbing...

Cheers!