I’ll touch on one special houseplant category: orchids, specifically tropical epiphytic orchids – which most cultivated houseplant orchids are. Frequently these will start to grow roots extending into the air and people are not sure what to do about them. The answer is: leave them be and DO NOT CUT THEM OFF. These plants normally grow clinging to trees in the rainforest. They gather water and nutrients from rain running or dripping down the sides of the trunks and branches, or directly from the humidity of the air. Those roots growing out the pot are how it naturally goes about its business. It’s the pot that’s the aberration here.
If your orchid does this, then it will appreciate an unusual form of watering in the form of a daily misting of the roots. Those roots are usually a sort-of-white to sort-of-brown colour with dull green tips; when they’ve been misted the tips will turn a brighter green for a while. Spray the roots until water starts to bead and drip off or trickle down them. This simulates how the plant gathers water naturally. Ideally you would spray with rainwater or soft, dechlorinated tap water if you have either; don’t use softened water because the softening salts can damage the plant. Distilled water, sometimes with a drop (and I mean a drop) of orchid fertiliser added, will also work. This doesn’t eliminate the need for other watering (I prefer top, but I’m sure there are many who would disagree), but it does reduce it. It could be a bit messy, though.
And for the love of dog, don’t water orchids with ice cubes.