Twisted Willow

I am having problems with a twisted willow i bought earlier this summer. Originally I overwatered it and it wasn't happy. Leaves went yellow and fell off. Repotted it and been watering once a week and it seemed happier but now the bottom half seems happy enough (can see new growth) but the top half looks pretty dead (see pics below). Thought willows like full sun so it's located round back of house, south facing in direct sunlight. Has anyone any ideas how i can get the plant back into shape?

 

Can I just ask why it is in a pot?
I have a huge one of these planted in partial shade. It does well there but it was originally in full sun and did just as well there. I moved it when it became too big.
Yours does look as though it could use a feed. Have you been doing that?

 

I'd also suggest sticking a tray underneath the pot to reduce the amount of watering you will be doing. I would also cut back the dead top growth and the lower growth should make up for it quite quickly.

 

I've got one earlier this year and its doing great, I would also recommend give it a good feed,

 

Thanks everyone.

I gave it some blood fish and bone early in summer i think. Haven't fed it since. What feed is best?

It's in a pot as I don't have enough border space to plant out, but will eventually plant out when i move house in a couple of years so keeping in pot for now.