Poorly spindly Mimosa tree- help!

Hello,
This mimosa tree has long been a joy in our family garden, currently about 45 tall. In recent years it has been so robust and strong and green it has needed pruning and keeping under control, and until about 2 years ago it was thriving with bouncy yellow flowers in winter.

Now it looks terrible and rather desperate and spindly- please see photo. We removed a bay tree growing near it in case it was competing but no improvement yet. The tree surgeon says he has seen many poorly Mimosa over the last couple of years.
Can anyone recommend a course of action for our lovely tree to recover its former glory? thank you in advance for any wisdom!

 

They are not totally hardy in my experience depending on species.
I assume you are somewhere mild in winter.

I also tend to think they are not long lived here in the UK mostly and dont reach a great age.

 

@Bluebell Q I'm afraid it looks pretty bad (although difficult to see details of foliage). It's possible wet conditions have done for it, and acacias don't recover well. Have a look to see if it has any seedpods on it. They grow very fast from seed, so you could soon have a decent replacement.

 

We inherited 2 large specimens when we moved here. I don't think they're very long lived in a rainy climate. One, multi-stemmed after being cut back hard by our predecessors, has just rotted and collapsed but has sent out healthy suckers on the neighbour's side of the fence.

The other, witha main trunk and normal branching stems, gets regularly pruned because it shades my polytunnel, drops loads of dirty brown petals and seeds on it and sends suckers out into my veg plot. I wish it would rot too.

 

Thank you for your thoughts! I was beginning to wonder if it needed to be removed as looking so poorly . Will be sad to do so…

 

Thank you for sharing! What a pain that it out out survival suckers on the neighbour’s side!

 

Yes, it does look pretty bad. You wouldn’t believe how lush it was only 2 years ago… thank you for sharing!