I'm 99% confident that it'll be perfect for you, but we need to make it 100%. You can buy Chempak products direct from the Thompson & Morgan website, and here's the link to the clematis food:
https://www.thompson-morgan.com/p/chemp ... /kww2556TM
Before you decide if this is really the right stuff, use the T&M contact page here:
https://www.thompson-morgan.com/contact-us
In case you need it, the clematis food product code is 14579. I don't necessarily have to see the fert's label, so just ask them about the following:
- Is P listed in their product description broken down as 14% P2O5 and 6.1% elemental P?
- Is the K listed in their description broken down as 32% K2O and 26.6% elemental K?
- Does the clematis food include Ca, Mg, and S? If so, what are their elemental percentages?
Just a reminder...
For our non-US members, I usually do all of the recipe calculations diluting in grams per liter/milliliters per liter. If you give me the volume of your watering container in liters, I can make the calculations easier for you.