If you want to green it up, you could feed it with pelleted chicken manure. That usually gives leaves a boost. I have a fatsia in my garden and it is one of the chicken's favourite shrubs to hang out under, so mine gets direct applications on a regular basis. It looks good on it though
Another really quick pick me up is liquid seaweed feed, diluted and sprayed onto foliage. That works wonders as well.
Longer term, you could mulch the soil with composted manure or soil conditioner. Both are sold in bags at garden centres. I would hold off over the summer as thick mulches can seal dry soil in and stop the rain getting through. It is a good job for the autumn though. Just make sure the mulch is not piled up against the stems of the plant,