Plastic Watering Cans

[Ian in Cumbria]

Hi JB

Do you mean impurities which have come in the rain or impurities (like moulds) which have developed in the water butt, maybe from the rain running down the roof? Bird droppings etc. I can see why you might not want to use the water in a closed environment like a greenhouse but can't see why you wouldn't use it on plants in the open which are subject to the same impurities by virtue of where they are growing.

Regards

Ian

[Johnboy]

Hi Ian,
Water butts are breeding grounds for quite a few nasties so that is why I was taught to not use them. When the nursery was in operation I had a sand filter and collected water off the tunnels was used but since I retired things like the filter are no longer in use.
I will give you an example of a friend who's plants always damped off and when I suggested he used water from the main his problems disappeared.
I had the old argument about rainwater being pure as the driven snow but sadly that is far from the truth. So although plants that get watered by the rain get fairly good quality water but it has never been in touch with anything else until it hits your plant. No time to breed anything.
JB.

[Ian in Cumbria]

Hi JB

Good advice. I'll take note. I don't think I've done any harm up to now because the butt was new just before the winter and I only collect off the greenhouse glass but it will be tap water from now on. (There's never a shortage here!)

Regards

Ian

[Monika]

JB, if one put a teeny-weeny bit of permanganate of potash into the can, would that not kill the nasties but not harm the plants? Or is that too simplistic? I do use the water from the roof of the sheds but only on shrubs, herbaceous plants etc., I would not use it on seeds or seedlings.

Just occurred to me: is permanganate of potash banned nowadays?

[Johnboy]

Hi Monika,
The answer is that I really do not know. Off a greenhouse it should not be so bad but water from the roof is a total no no to me.
JB.

[Beryl]

I always keep a netting bag of charcoal in the bottom on my water butts. It keeps the water fresh but I never use it for seeds and seedlings as Johnboys says sterile water is best from the tap till they have got a good start. Then I see no reason not to use it.

Beryl.

[oldherbaceous]

I too, use rain water on any larger plants, without any ill affects.

[John Walker]

I agree that using tap water is a good precaution against seedling diseases such as damping off, but I collect as much rainwater as possible in a large recycled plastic tank fed from my cottage roof. I use this for general watering in my greenhouse and outdoors, but not for seedlings under cover (part of the problem with damping off is it is encouraged by the close and humid conditions in a greenhouse, especially early in the year).

Collecting as much rainwater as possible in butts/tanks relieves pressure on mains supplies of drinking quality water, for which demand continues to grow. As an earth-friendly gardener, using tap water for my garden is a luxury I reserve for watering seeds and young seedlings. By harvesting as much rainwater as possible (which is free) I'm reducing demand for tap water, which is the product of an energy-intensive process (collection, purification, pumping/transport, etc).

If anyone is looking for a big recycled water storage tank (or a smaller butt) then Smiths of the Forest of Dean are well worth a look: http://www.smithsofthedean.co.uk/Recycl ... ainers.htm