Is it better to use rain water or city water for watering your garden?
Question:
I am planning a new home flower and vegetable garden and am wondering if it would be better to use rainwater rather than city water?
Answer:
Neither is bad, but the answer depends on which plants you want to grow, what your budget/available workload is, and your perspective. As with many things, it’s balancing trade offs. The benefits of rainwater are that it’s generally pH neutral, it has no intentionally added chemicals, it’s ecologically friendly, and it’s free (although you may need to make an initial investment is rain barrels and/or a catch system).
The downside is that because it’s untreated, it may also contain contaminants from animal feces or contact/atmospheric pollutants (particularly if the rain is being collected from a rooftop), which would mean you would want to be careful how it’s applied. Overhead watering would potentially leave contaminants on the outside of fruits and leafy green vegetables, so they would really need to be washed well before eating (and you would probably just want to put in drip irrigation–see here and here–to minimize the risk, which would be additional cost and effort). This is less of a concern with the flower gardens, where you aren’t eating anything from the bed. Also, if you collect more water than you use, you can also have algae issues in the barrels or reservoirs.
Contamination risks are far lower with municipal supply because it’s treated, but then you also have any additives from the treatment process, potentially hard or soft water issues depending on the pH, and you pay for it each time you use it. Elsewhere in the country, this might also be impacted by any restricted usage from drought, but that’s less of a worry here in Maine.
As I said, there isn’t really a *right* answer, but hopefully the above information can help you decide which works best for your garden philosophy and budget. You could always adopt a hybrid approach and use the rainwater for flower beds and municipal water for the vegetable garden. This would help you adjust to the particularities of the season’s rainfall, too.
Happy gardening.