You need to keep in mind they're a cactus and need good drainage. They're suited to subtropical/tropical climates and don't like to get down to freezing temperatures. They also like to be out in the sun.

I grow mine outside, but I only got three fruits this year - last year I got four. They get huge and do like full sun or partial shade. Here's a photo of mine from September - photo taken at night:

This flower (and the bud below plus one above) made fruit, but I had to hand-pollinate it at night soon after the flower opened. When the fruit was almost ripe, I put protection around it to prevent possums or raccoons from stealing it. I also put a bunch of prickly bromeliads around the one near the ground. I've given up trying to control this plant. If I try to move the branches, they are likely to break off, but they are easy to root.

Mine started out as one of those "grafted" cactus. With the bright colored fella on top. Well that part died and rotted off and I noticed the bottom part was wanting to survive so I thought what the heck. I had no idea what it was... Boy they are a stringy plant! I moved it inside for winter into a well lit sunny window. He has about 6 little "arms" now. They are and odd thing! I just water when it's dry? Have Fed him a couple times. Thank you for your input and beautiful picture!! I'm betting Kansas isn't the best place for them.