Hi, Marguerite > I need some advice about hard water from my well. > I have > always read that the water softeners commonly used on houses will kill > plants. A websearch turns up lots of information, for instance > http://ag.ndsu.edu/pubs/h2oqual/… One of the quotes is > For every grain of hardness removed from water, 8 mg/1 (ppm) of sodium is added. This is fairly typical of the old types of water softeners, which mostly used salt (Sodium chloride). There are a number of newer types, and it might be worthwhile to talk to someone in your neighborhood who installs wells and treatment systems for the particular minerals in the water in your area. Saving rainwater: As much as possible, which means a big storage tank. The amount you normally receive as precipitation and the amount of roof area available will determine the size of the tank. If you collect from your roofs, the first rain will probably wash a lot of dust off the roof, so you might be reluctant to save it, or perhaps divert it to a small secondary tank that can be filtered. Ken