Allotments 4 All

There isn't going to be an easy way, there never is with gardening! I think I may have to get someone in to dig a hole in the lawn a couple of feet away and put in a strong wooden post at an angle. then attach the tree to that.

A metpost and fence post support is an arrangement that is both sturdy and can be removed if no longer needed.  As the tree is leaning more above the present pole, a taller pole is needed.  Asymetric pruning can also help.  We had a leaning tree in our old garden in a very windy spot, and it was never an issue. But that was on MM106 rootstock, which makes for sturdier trees than miniature. 

You mentioned metal curtain rods  - presumably metal tubes are narrow and strong enough to drive into the ground and would be preferable to the excavation needed for wooden posts?
If so, maybe use a couple of fruit cage poles, they're about a metre long each. The first will be short enough to drive into the ground with a block of wood and hammer, then you just slot the second one over it and screw them together. One or two of these either side of the tree and a bit of strategic tying in should keep it upright.

Don't worry about duplicate pictures. Your message is clear.
A tricky situation. I can only wonder whether you have any vertical structures you can tie a horizontal rope to. But such an obstacle in your garden wouldn't be at all convenient ☹️

Otherwise perhaps more practical but quite labour intensive, can you dig through your rubble to get a hole big enough to concrete in a sturdy tree stake?

Oh dear, I seem to have mucked up my post, only wanted one photo but don't know how to get rid of the others, Ed - can you help please?  Also, sadly I don't have a quarter acre plot any more, just a small back garden, no idea how to change that!!

Hi! Three years ago I planted two dwarf fruit trees in my garden. They are doing well but they need a decent support. Unfortunately my garden has very little soil until you reach the rubble and rubbish, I grow everything in raised beds. So far I have used old metal curtain rods to support them, but as you see from the photo of the apple tree it's bending and once the weight of the fruit is on it we will be in trouble. Any suggestions please? 

No problem davholia. Go ahead and feed and mulch. Only mulched mine yesterday. Fed them a couple of weeks ago 
Morrisons are doing a deal of 2 bags of mulch for £6. It's good quality.

Plus netting to keep the birds and pigeons off!

I'm thinking that the amount of fruit you get will already have been determined by how many flowers you had and how many of them set fruit. I haven't looked at mine to check whether I'm right about the timing though.

I imagine you can marginally affect the quality of the developing fruit. The mulch will help to keep moisture in the soil which the growing fruit will need. And the weeding will help cut down competition for moisture and nutrients. And all of your proposed actions will help the long term health of the plant, so nothing to lose and all to gain!

Tomorrow I am going to weed, feed and mulch the gooseberries. Is it too late to do this? Or can I still get a good crop of my favourite fruit?