Hi guys, I have a small patch of potatoes where about 50% of the plants died/are dying with the leaves just turning brown and withering away.

I also have a tomato patch which has looked good for the last month, but this week there has been some intense, persistent leaf curl on 3 or 4 plants and tips of leaves are starting to turn brown on a few bottom branches.

First off I'm wondering if it's potentially a potato disease that is getting over to the tomatoes. If not, what is wrong with the tomatoes? I don't care that much about the potatoes, in fact, I already dug a few of the plants and got a bunch of nice, little potatoes. I care a lot about the tomatoes and don't want them to wither away.

For some reference, I live in the Sacramento Valley, zone 9B. It has been a relatively cool spring. The potatoes are not seed potatoes, they were just sitting on a shelf too long and started to grow, so I planted them. I have heard this frequently leads to disease but I don't know if that's true.

First 2 pictures of unhappy potato plants

Next picture of happy tomato plants, this is what the majority of the foliage looks like

This is the leaf curling, it's looked like this for about a week.

This is the browning of the bottom branches