Not usually. If you want to get fancy, rainwater is primo as far as plants are concerned, but tap water will do fine. Ideally it should be room temperature. There are some people who like to toss the dregs of coffee or tea (as long as it doesn’t contain dairy or sweetener) on a plant as a mild fertilizer and pH balancer: coffee and tea are acidic, while tap water skews alkaline, especially if you have hard water. But don’t over do it or treat it as a substitute for normal watering. Others like to use ice cubes to water orchids and other moisture-sensitive plants in small pots to guard against overwatering. However, some experts and gardening books advise against this, arguing ice cold water can shock the roots and stunt growth over the long term.