Victoria plum tree aphids?

[sabulous]

I was just outside having a look at our victoria plum tree and noticed that a lot of the leaves had curled up and were covered in little bugs. Most of the leaves that weren't curled up were also covered in these bugs especially on the underside. There were also some larger red/orange and black beetle looking things on some of the leaves.
There are loads of baby plums on the tree and they looked fine (so far).
After some googling it seems like it might be aphids?
What do I do about this?
Some websites say soap and water spray but I also read in a few places not to do that because that also kills things that will eat the aphids.

I'm incredibly inexperienced when it comes to all things gardening, the tree was already there when I moved here, but I love my plums and making plum jam every year!

If someone could tell me what to do I'd be so grateful!

[FB.]

If the tree is established and generally healthy, the aphids will be tolerable. They don't usually cause problems with the fruit. Unless the tree is being severely stunted by their attacks, I would not worry.

Soapy/washing-up-liquid water spraying is often used to get rid of aphids. It is quite possible that the "red/orange/black" are ladybird larvae arriving to eat the aphids, so you may not need to take action.
Aphids are worst in warm and dry years. The warmth allows them to grow quickly, while lack of rain means that they don't get washed off by heavy downpours.

Now that the leaves have curled and are aphid-damaged, the tree will probably drop some or all of the damaged leaves in a few weeks time, no matter what you do. It will probably grow more leaves somewhere else.
Young leaves are most favoued because they are soft. Aphids find it harder to suck sap out of older leaves that are thicker and tougher.

So....in summary....

If the mature tree has managed growth of new shoots of at least three inches (about 7.5cm), it should be strong enough to shrug off the aphids.
On very young trees, it can be advisable to get rid of aphids, so as not to stunt its growth.

[sabulous]

Thanks! I think the tree has been there for quite a long time and there is no risk of it's growth being stunted as it's massive! I'm quite relieved by your answer as I was kind of wondering how on earth I was going to spray a whole big tree! I shall keep an eye on the orange/red/black things to see if they are munching the aphids.
Thanks for the help!