Ideas on how to neaten up this hideous edge....

[Hombadigada]

I only rent the house so don't want to spend too much....

You could scoop a bit of mud out between the slabs & the edging & put some slate chippings or gravel down there.

Either gravel as a pp says, or mix loads of grass seed with some damp compost or soil and use it like grout to completely fill the gap. Keep watered.

Pea shingle gravel 10mm

About £2 a bag from b&q. One would do it

Plants, stick some evergreen creeping herbs down there, they cover a multitude of sins.

savvygardening.com/evergreen-groundcover/

Stick some gravel on and plant a load of Mexican fleabane. You can grow it from seed and it spreads really easily. Very pretty pink and white daisy typed flowers .

Thanks for the suggestions everyone. I'm not sure you can actually tell from the photo but the flagged part is raised up from the grass - there's a drop of about just less than a foot down to the grass.

I do like the idea of putting some gravel in those small gaps, but they dont have a solid edge all the way along, again it's not easy to see on the pic, but there are gaps where the concrete on the outside has crumbled away.

Chamomile?

Something like nasturtiums would spread and cover the edge (and weeds) by , say, mid summer. Poke the seeds in, and they usually like gravelly soil.
I have London pride in a few odd places. It's perennial and evergreen if you can get it.

Saxifrage would be another idea, nice mossy looking mats all year, pretty flowers. I find it really easy to spread about, just pull off a chunk (with roots) and shove it where you want it

www.alpinegardensociety.net/plants/mossy-saxifrages/

I would paint them with black masonry paint and then grow creepers in the gap to cover the edges and trail down towards the lawn. Which plants will depend on how much sun it gets.

@lightningstrikes

I would paint them with black masonry paint and then grow creepers in the gap to cover the edges and trail down towards the lawn. Which plants will depend on how much sun it gets.

North facing garden so doesn't get much sun, what creepers would you recommend?