Clematis Yellow Leaves

[How Do I]

I've been growing clematis for several years. This is the first time I've run into yellow leaves - some green veins. Iron? Magnesium? Can you tell from the photos below what exactly these plants need. I say "these" because the mother plant, I layered two years ago. It looks like I have several new plants there this Spring, but I haven't checked underground yet so I don't know if they are all still connected or not. Just took these pics a few minutes ago so they aren't real clear but hopefully enough to tell what they need. All plants are doing the same thing - which makes me think they ARE still connected at the hip. Just a few leaves, hit and miss on each plant.

ETA - Just double checked the new plants. They have all rooted, but they are also still connected to the mother plant.

[oregon woodsmok]

I have never grown clematis, but I suspect that it is a good time right now to separate the plants and move the little ones to wherever you want them.

Yellow leaves is usually nutrition. I always think "iron" when I see yellow leaves. However, the best way to know is to get the soil analyzed. Acid loving plants can't uptake iron when the soil is too alkali for them. But I have no idea what sort of soil clematis likes.

So: soil test, feed them, maybe give them some chelated iron.

Any advice you receive from anyone who actually grows clematis is going to be better than what you've received from me.