How is this possible?
D Simmons, Lancashire

A If the tree was neglected before you inherited it, it’s possible the rootstock sent up suckers on which the fruit grew, while the plum branches didn’t fruit (the Victoria plum will do that sometimes).

If there’s only one main trunk with both sorts of fruit on the same branches there are two possibilities.

One is that the flowers weren’t properly pollinated so you’ve had stunted, semi-formed fruit.

Even though Victoria is self fertile, the pollen still has to be moved from flower to flower, which won’t happen if it is cold, wet and windy at blossom time and bees aren’t working much.

The other possibility is that the tree is suffering from poor growing conditions so give it a dose of sulphate of potash now (1oz per square yard) all round the tree, plus a generous mulch of compost and general fertiliser such as blood, fish and bone next spring.