[Eightball]

Had nasturtiums growing all over my plot last year. Lovely flowers, tasty leaves and the bees loved them. They spread like crazy and obviously set seed. I've got some coming up in my potato mounds.

Do you think they would steal much nutrients from the potatoes? Was thinking of leaving them be but thought I would ask peoples opinions.

[Growster...]

I'd leave them there, Eight, they always brighten up any area!

I can't think they'll take that much from your spuds, and you never know, the spuds might actually like them there!

[ptarmigan]

I'd leave them for the bees and because the are just bright and cheerful.

[Comfr3y]

its considered a good companion plant although not specifically for potatoes I cant see the root or the leaf system competing.

https://porchsidegardening.wordpress.com/2010/07/02/top-ten-companion-plants/

Its related to brassicas but not a brassica for rotation purposes, I think -