Thank you for your question. Color changes in leaves are typically an issue of nutrient deficiency rather than wilt, which is not apparent in your plant. What fertilizer have you given it? It may have some type of virus, but we should rule out the obvious fertilizer issue first.

We have to admit that we've never fertilized it.  What do you suggest that we use?  Thank you for your help!

There are several time release balanced (10-10-10) fertilizers, both chemical and organic, on the market. Water soluble ones aren’t recommended for outdoor use; they just get washed into the aquifer with weather like this! BTW, the first number in the trio is for nitrogen, which is needed for green foliage. The second is for phosphorus, necessary for healthy roots. The third is for potassium, essential for flowers and seeds/fruits. They are percentages of the total container by weight. So 10-10-10 has equal percentages of these 3. I suggest you look for a fertilizer that also has ‘micronutrients,’ which are the other nutrients (boron to zinc) that plants need in smaller amounts. Good luck!

We'll try using the suggested fertilizer.  Thank you and we really appreciate your help and advice!

Welcome!

I just wanted to recheck on what's going on with our clematis.  I did use the fertilizer (Pennington Ultragreen All Purpose 10-10-10 on June 11.  On June 27 I used a bit more because I thought I may have skimped at first and sprinkled some more (about 3 Tbsp.) around the base within about a square foot.  I scratched it into the soil and watered well both times.  I'm bet there is no immediate miracle cure and it takes a while. But, the plant is doing what it did last year and the ailment is now spreading up the plant.  If this is normal for this season and by following the recommended directions on continued fertilizing, will the plant be better next year?  My husband and I are not green-thumb gardeners and aren't sure on how these things really work.  I've included new pictures of the plant as of today and the fertilizer.  Thank you for your input.

I believe the red tissue illustrates the difference between mobile and immobile nutrients. When a plant is deficient in a mobile nutrient, old growth will show symptoms of the deficiency, while new growth will appear 'normal.' Phosphorus is a mobile nutrient, and it takes a plant time to be able to transport and utilize nutrients, generally, so there is no 'overnight' cure. And, the leaves may not be able to recover from the earlier deficiency, so die and fall off. What (hopefully) is not affected is the woody tissue, and that should survive over the winter. So, I think that if you are diligent in following the label directions, you should not have this problem next year.  

However, the leaves are also exhibiting symptoms of powdery mildew, a common malady of many species, especially in wet, humid spring-into-summer years. Here is an Extension diagnostic page on this problem:  https://pnwhandbooks.org/plantdisease/host-disease/clematis-powdery-mildew

As it says, you must apply a fungicide preventatively, and the only one of those listed for homeowners is the Safer Garden Fungicide (H).  I think you can assume that this will be an annual problem, so should put it on your gardening calendar for 2021. Hope this is helpful.

Kristena, 

Thank you again for your informative and very helpful advice.  Hopefully, our clematis will have a healthier season next year!

Patty and John

Along with us!