It's an Allan Taylor song:

Chorus:
And if nobody wants to talk to him
Well that's okay
'Cause he's not too keen on talking anyway

Old Joe is a man who just wanders around
He says he moves much better when he's on his own
He walks the lonely roads from town to town
He pushes his home around in a broken cart
And he wears his ragged clothes and he plays the part

Old Joe is the man who'll fix the door
When the hinges break and it catches the floor
Then he'll spend the night in the barn on a bed of straw
In the morning he'll be gone when you try to find him
Some flowers by the door is all he leaves behind him

And when it's winter time and the wind blows cold
And the sheep are settled in the fold
People wonder where the old man goes
'Cause he disappears for two or three months or more
But he'll be back on the road in spring just like before

When I was a boy he was an old man then
And the old folks knew him when they were young
And now I'm grown and he's still around
I wonder if he's one of many that look the same
Or maybe he's just a small part of the game

Apparently, it's a real-life story:

[1983:] Old Joe was known by many who travelled in the South-West of England. Being a tramp and wandering throughout Devon and Cornwall, he was difficult to find. I met him just outside Wadebridge and remember vividly having tea and bisquits around his campfire at the side of the road. His skin was almost black, partly due to the sun, but mostly from the engine oil he covered himself with to keep warm. Sitting upwind from him, it was a pleasant afternoon. Joe died three years ago. (Notes Allan Taylor, 'Circle Round Again')