Help in identifying what this is?

First year hop crowns, I have 8 different plants. Planted all in the ground with bagged garden soil. All plants have been in the ground for a little over a month and are growing like crazy. A couple days ago I noticed the ends of the leaves on my Magnum plant were drying and turning brown. We've had a lot of rain, followed by a mix of hot sunny days and cool rainy days. I've not watered or fertilized, however I think the garden mix had some nutrient in it. The seven other plants look fine. Any idea what could be the issue?

There is a good chance this is root damage, caused by the roots not getting enough of a wet/dry cycle and staying too moist. It shows up like a nutrient deficiency because the plant has made these lovely leaves and now cant give them enough food since the root mass has diminished. If you can find a way to keep the direct rain off of them with out reducing air flow and increasing humidity that would help.
the other thing you can do is take some sanitized toenail clippers or cutting implement of some kind and clip off the very tip of the growth tip. This will slow the growth of the plant temporarily with out hurting it giving the roots a little time to catch up. There is a catch though the plant will typically then sprout a new branch/growth tip at every node down the bine/trunk which can mean a lot more pruning if you are trying to train your hops into one bine.

But honestly if there is some drier weather coming up just wait and see. Don't give them any nutrients; if the others are fine then clearly they have what they want for now

Thanks for the reply. I don't believe I could keep the rain away from this plant. I will try to consider a method in doing that though. I'm hoping it dries up a little soon.

Seeing that these are first year crowns I am pruning to 4 bines a plant in hopes to allow the roots to develop, and also hopefully yield a few cones this year. I had just last week pruned the bines down to 4 each. Could this of had some kind of effect on this plant? Thanks!

pruning wont create that type of damage as far as i know. this looks very much like root damage from moisture.

last year i thought i had it all worked out on how i would grow hops down in Florida, i even picked hops with a higher tolerance for humidity and moisture. But alas i managed to plant them at the worst time just before the edge of a hurricane passed over central Florida. So right when they had just put out a few nodes we had like a month of rain and ridiculous humidity. The rhizomes literally rotted while the bine and roots were still alive.
Two actually survived because they had put out a fingernail sized rhizome but but it was a major step backwards from what i had started with so i just let them go.

if you just pruned them see how they do but i would looking into putting them into a raised bed of some kind and maybe adding some sand to your medium to aid in drainage.

Thanks again. I think I'll give it time and see what it does. It looks like it's only one bine so far so hopefully it pulls out.