passionfruit deficiency?

[bigpepperplant]

Hi, I recently planted a passiflora edulis and have noticed that, though it's growing fairly happily, the leaves are going a bit yellow. My instinct is that it's some sort of mineral deficiency - it's in a well-manured raised bed in a fairly sheltered spot. I fed it with seaweed yesterday. Anyone know if I should be doing anything else?