Turning on the faucet or hose may be the easiest method for watering indoor and outdoor plants, but there are plenty of ways in which household water can go directly into the garden and not down the drain, saving both money and resources.
Not only does it save money and resources, but recycled household water can also be more beneficial than water straight from the tap! Here are five ways to make your water do double-duty:
1. Collect Roof Runoff - If your area gets enough rain during the warmer summer months, try installing a rain barrel or similar device to divert roof runoff to the garden. (I would love to install the clever Raindrop Mini at my house!)
2. Reuse Pasta and Veggie Water - Water used to boil pasta and vegetables is often nutrient-rich and great for plants. Similarly, water used to rinse fruit and veggies could be reused by placing a shallow bucket in the kitchen sink.
3. Collect Cold Shower Water - Even with an efficient hot water heating system, it can take a minute or so for bathing water to heat up. It’s a little extra work, but keeping a bucket in the shower could provide enough water to take care of daily indoor watering.
4. Recycle the Aquarium Water - Aquarium water can act as a natural liquid fertilizer for plants (as long as you’re not adding chemicals or salts to the tank), but most sources recommend limiting aquarium watering to once a week.
5. Reuse Unwanted Ice - Don’t just dump that glass of ice down the drain or the cooler from last weekend’s BBQ on the grass, spread it around plants and let evaporation do its thing.
(Image: Raindrop Mini from Bas van der Veer)
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Great ideas! The last one reminds me of how my boss convinced the ice cream truck man to dump the extra ice into the planters around the neighborhood at the end of the day.
There is a copper outtake pipe on the a/c unit outdoors where the humidity water taken from the air inside goes outside. I attached a rubber hose to that (the thin kind used to connect drip watering systems) and clipped the end to a gallon watering can. In the summer, I collect as much as 3 gallons a day. It's great for watering plants because it doesn't have the chlorine in it that tap water has.
If the roof in question has asphalt shingles (many do), then runoff water should not be used for edible plants. The shingles leach heavy metals into the rainwater, so the runoff is great for watering ornamental plants/trees, but not for eating!
I think I read that if your soap is biodegradable (or maybe even if it's not) it's OK to water plants with sudsy water.
@cammit -- your boss is brilliant!!
Thanks for the tip about the run-off from asphalt shingle roofs. I did not know that.
If your veggie or pasta water is still really hot, you can even pour it on weeds to kill them. We got rid of English ivy this way.
If you have access to the water output from your washing machine, we usually get a rain barrel's worth each run - plenty enough to go over our garden and lawn (although we've got a tiny lawn).
I have used Aquarium water to water my garden but your ideas are just great! Very helpful article.