Hi, A neighbor has asked me to help him with some of his plants. I am unfamiliar with several of these. The first photo shows a plant that I was told was a philodendron, but I'm not sure. It is tuberous and I'm afraid of over watering it. Can you identify? Second photo is of an umbrella plant. Not sure that you can see the 'dust' on the leaves, but trying to rule out that this is some sort of bug issue. Third photo, I don't know if this is a cactus or succulent. Watering needs? Thank you!!
Denver County Colorado houseplants
The first is a spathiphyllum, a relative of philodendron. It is tropical and comes from areas of high humidity. The roots of all plants have to breathe air, so don't keep it constantly really wet. Water it over the sink and let it drain well before putting back in a saucer or container. It would really prefer rainwater or bottled water. Water when your finger, put down 1" into the soil, feels like it is getting dry. If you get yellow leaves, it is being overwatered.
I can't see anything on the next. I don't see small yellow or brown spots, which would mean it has a sucking insect infestation. It looks healthy for me. See what a tepid shower will do for it.
The last looks very much like a spineless cactus (I am 98% sure), but a Google image search failed to turn this particular one up. Please write back with just this one photo with the header, "Is this a spineless cactus?" and we will hope that someone with cactus experience will pick it up.
Thank you for writing.