East northants, United Kingdom

I have a plum tree that was so infested in June with aphids they must have been several milimeters deep nearly all over, not just the leaves, the trunk, all branches, dropping off to the ground below, it was horrible. I shook off at first but as the ants had found them & they were firmly stuck with honeydew this did not work. Insecticide I had to hand was useless, I tried spraying with Provado but no spray was effective as the beggars were protected by curled leaves. I cut off as many leaves I could reach & burnt them. All to no avail, I ended up severely pruning the tree in July, & lo they disappeared. The tree, which incidentally was about 10 foot tall (now about 7) loved being pruned & put out a lot of lovely new growth....BUT this new growth is now re-infected.
I want to treat it so that I can try & prevent any egg laying or whatever it is they do to reproduce!
I should have realised that something was wrong in the Spring, it was smothered in blossom which all turned brown & fell off in clumps.
Would a winter wash work? As they appear flightless can I wrap the trunk & branches in anything?
Would a systemic treatment be any use? As it has no fruit (well 2 plums) I do not mind if initially it bears no fruit. I honestly can't see how spraying with anything when it is in leaf is going to work as I have no hope of reaching every leaf, so am really looking for something I can do before the Spring, otherwise I'm afraid it's the AXE!! Nothing else was affected thank goodness.

• 9 Sep, 2016