Apple Tree Woes

[boydzfish]

My last surviving fruit tree, a small apple one has suffered with brown spots every year; I think it might be bitter pit. Apparently this shows up because of calcium deficiency and the solution for this is mulching but this hasn't helped at all this year. So now I am looking at either digging it up (I would rather not) or sprinkling calcium around the base to wash down over winter to the roots. But I haven't been able to find anywhere that sells it and does it have to be horticultural calcium?

[boydzfish]

[galina]

More than calcium I think you got it half right with the mulching.  This is to keep water in.  But if the tree is in a dry spot and free-draining that may not be enough.  Additional watering as the fruits swell will help. 

We had bitter pit when our apple tree was crowded by a neighbour's pear tree the other side of the fence.  It was a real pity when they felled that tree, because half of the crown was leaning into our garden with nice pears, but as soon as the water and nutrient competition from the pear tree stopped, our bitter pit stopped too and we are now enjoying good apples.   

[Palustris]

If the brown spots are on the surface of the apple then it is Scab. Bitter pit spots are under the skin and in the flesh of the apple.
We bought Calcium from a fairly standard Garden centre. Vitax do it I am sure.
http://www.amazon.co.uk/Calcium-Carbonate-1000g-very-Powder/dp/B00CWMA702/ref=sr_1_1?s=outdoors&ie=UTF8&qid=1444115367&sr=1-1&keywords=calcium+carbonate

[Digeroo]

I am rather surprised considering your location that you have any calcium deficiency issues. It will be in the water.  What is your kettle like?
I would suggest a good dousing with tap water.
Some of lyneham is on sand and some limestone, so depends exactly where you are.   Are you where the red locator on the map is?

[Gavin63]

If it is bitter pit Calcium Ntrate is the most effective treatment; use a 1% sloution when the fruit is growing next summer at intervals of 2-3 weeks adding a few drops of a wetter to aid spreading.