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  • Writer's pictureKate

Activity of the day: Water, water everywhere: use your waste water to keep your plants happy!

The water butts have run out of rain water here, so we've been getting back into using "grey" waste water for the plants.

Grey water is water that's been used but hasn't gone down the loo (if it's been mixed with wee and poo it's called black water).

Pictured above are our main grey water recycling devices. As you can see, they're not very complicated. The bucket and watering can go without explanation; the black rectangular thing that the watering can is in is our washing up bowl.

There are a few main rules with grey water:

  1. Think about what you're putting into the water to make sure it will be OK for the plants- put it down the drain if it has anything likely to be harmful in it- such as strong cleaners. Don't use dishwasher water (even if you can get at it) - dishwasher cleaners and salt will be really bad for plants.

  2. Don't use bath or shower water on plants like salad where you're going to eat the bits that the water has been on - if your bottom has been in the water, eating that salad could give you any bugs that were in your poo... and a very nasty tummy upset.

  3. NEVER store grey water- it will contain bacteria and other germs which will grow if it's left in a container. It will quickly go smelly and could cause illnesses if then used or touched. Filtering grey water through soil straight away will clean the water.

  4. Saying that- if it's really hot, leave it to cool for a little while- your plants aren't going to appreciate being cooked!

One useful thing to bear in mind is that mild soap is a great way to treat plants for greenfly: If you use mild dish soap to wash up then water your plants with the leftovers, you'll have a two for the price of one situation every time!

If you're in a house, kitchens are usually near to an outside door, so carrying out the washing up water is fairly easy (and if you have little people interested in watering very slowly with a small watering can, you can pour the water into a bucket then they can refill a tiny watering can to their heart's content and you get the dish washing bowl back- that would be why the bucket is in the picture above!).

Bath (and shower, if it's over the bath or you have a way to collect the water) water is more difficult, but can be used with a siphon pump or other small pump.

We had one of these siphon pumps for years when we were in our last house- it meant we could grow bumper crops of pumpkins every time as the bath was by a back window and the drop onto the garden meant water got easily down onto the vegetable plot.

Our system now is a bit more complex as the bath water has to get over a flat roof before it gets to the garden, meaning the pipe needs more pressure to flow than the siphon pump can manage. So we have a small hand bilge pump and a big hose which reaches between the bath and the garden- slightly daft but very effective! A powered pump would be easier, but we do have a fair bit of volunteer labour as the kids aren't allowed on the roof unless they're helping... We also have a squishy bucket to chuck water straight out of the window onto the green roof:

And here's hoping this can help with getting bumper crops and very small water bills this summer!

As it's now Easter Weekend we're going to have 4 days without Activity of the Day posts, but we'll be back on Tuesday with a whole series on keeping homes cool in the summer- with ideas for activities that everyone can join in with to keep the temperature down during the lockdown.

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