I have often read that pumpkins and potatoes should not be planted near each other, and I've always followed that advice.

As they are not closely related , I suppose common diseases etc are not the problem. Is it simply a question of competition for soil nutrients and/or root-space the soil?

The reason I ask this now is that I have just found (in New Zealand's southern hemisphere spring) tiny bits of potato sprouting in the compost I've been using for planting out butternut pumpkin seedlings. Is it sufficient to remove the sprouting potatoes (to rule out competition) or is there something more "sinister" that may be lurking there that I should be aware of, and which might cause trouble for the pumpkins?

With grateful thanks for any light anyone can shed.

Davi Tupinikiwi ( love the name! Dude! ) hello from Colorado and welcome!

I've grown both, but never together, mainly because ( I.M.O) they both require the same nutrients but different watering needs. Lucky for me ,the soil around here needs little tweaking for them. The other reason I don't couple them up is the growing habit of the pumpkins is viney ( is that a word? ) and spreads all over the garden and makes a good weed supressor, which won't do my potatoes any good.

Another thing that needs mentioning, is that pumpkins attract squash beetles and I really don't want to give them a taste of something they might like! And since I really don't care what they do to my pumpkins ( I only use them for fall decor ), I do care about my potatoes.

What I have found is that asparagus doesn't seem to mind sharing some space with either, as I've got that in a few beds.

Anyhoo, I hope this helps, even if a little bit.