Small triangle bed

[NorthFaceofthelaundrypile]

Hoping for some inspiration!
I have this little triangular bed that I want to fill.
It's south facing, and probably the sunniest part of the garden.
I would like ot to be as low maintenance as possible, though happy to add in some bulbs in the autumn.
Preferably pinks and purples. I panic bought lavender yesterday, as I just wanted to get something in there!
Any ideas of what I could plant, and where!
I’m thinking once it’s done, I shall top it all with wood bark.
many thanks!

Salvia is also usually purple or white.

Purple goes well with yellow. Coneflower would be a nice look. You can also get purple Coneflower/echinachia.

So could I just fill up the remaining bed with them…. And leave them there over the winter?

Have just had a look at pics and they’d both be perfect, and have a lovely cottage feel.
The bed is just over a metre square. Do yiu think I could fit a dahlia in the middle, or is less more?

Phlox?

https://www.rhs.org.uk/plants/phlox/border/growing-guide

These three plants would all be perfect.
Please excuse the basic questions, but how do I decide where to plant each one, and would I need more than one of each?

If you look on the labels (or google) it’ll tell you how tall/wide the plants tend to grow. That’ll help you work out how many plants you want - eg if a plant grows 1m wide and you’ve got a 2m bed you’ll want 2 of them. Usually you want tall plants at the back and the shorter ones in front so you get a nice display. Some lavenders can get pretty big but if you’ve only just planted them you can dig them up carefully and move them if you want to.

Btw I think lots of dahlias (there are so many different varieties!) tend to be tall flowers that grow in a small clump, so you might be able to fit in several and you’d probably want them at the back. They might need supported with a stake as they grow.