You might want to consider using rain water or water from a dehumidifier - both are essentially deionized and are similar to distilled water.

There are actually 2 things to consider in your question. One is the actual level of chlorine/fluorine in your water. It's a certainty that letting the water set out doesn't reduce fluoride levels, and a near certainty it doesn't reduce the amount of chloride in the water ..... and a near certainty that it doesn't reduce the amount of chloride.

Only in water purification systems that are throwbacks to the 50s & 60s will you find a volatile form of chlorination. This is because of the short short half life of the compounds formerly used. Newer forms of chlorination use chloramine, which doesn't gas off. The fluoridation process (of drinking water) has always used a compound that is nonvolatile, so it too, remains in any water left out to rest for any length of time. As water left out evaporates, it leaves the elements/compounds dissolved in the water behind, which actually increases the concentration.

The second consideration is the TOTAL of all dissolved elements/compounds in the water. ANYTHING dissolved in the water contributes to the TDS (total dissolved solids) and EC (electrical conductivity) of the water. These measurements are valuable to greenhouse growers because they help to determine safe levels of solutes in the soil. If their concentration is too weak, nutritional deficiencies are assured; too strong, and it becomes difficult for the plant to take up water and the nutrients dissolved in it.

Using distilled water eliminates the extra ions dissolved in tap water, which can reduce the TDS/EC of the soil solution. This can facilitate water uptake and make it easier for the plant to move water to distal parts, like leaf tips & margins - so spoiled foliage is greatly reduced.

All this is pretty much a nonissue if you're using a suitable soil. By suitable, I mean one that allows you to water copiously, so that you flush salts from the water and prevent them from accumulating without worrying about root rot. If you're using an appropriate soil and watering correctly, chlorine/fluorine are usually never a problem, and you shouldn't NEED to worry about using distilled water, though it can still be helpful if you want to. Be very sure though, that your plants are getting the Ca and Mg they need - especially if they have been in the same soil for more than a year or two. Most soluble fertilizers don't supply these elements. SOME, is usually dissolved in tap water, which is why you need to be extra vigilant if using deionized water in any form.

Al

ACBROSS~~Thank you!! I was beginning to think I was the only one that had this prob. I have been using water from the dehumidifier and it is good, but for my Spider plant, she still likes Distilled the best. One good thing about moving to Idaho is the water there is good. Can drink it straight out of the tap! Will be good for the plants.

I can't tell you what it is about the tap water and plants, but thank you for letting me know I am not alone in this. :)

Marjie

Switching to rain water was one of the best things I ever did for my plants.

Joe

What to do if there's no rain?

As of winter 2011/2012, IL snow/rain % record is below average.
This winter we had three days of snow, under 5", and 3 rain storms.
Humidity is an all time low.

Why does some tap water harm plants?

a couple nights ago I was thinking this same topic. I wondered if tap water was boiled, chilled, then used to water plants would work..especially for people who have hard, or similiar to Acbross's water.

Marj..don't know if you're around, but are you saying, water in your last house wasn't drinkable? If so, that's awful.
You'd think, all of US's water would be safe..not only for plants, but PEOPLE!! Toni

toni-- the water here just taste bad, I don't like it, and I love drinking water. The water in Preston was good to drink out of the tap, clean, clear and it tastes real good.

I know water is safe to drink, but some states just taste better than other. (imo of course) And for some silly reason, my Spider Plant isn't as "spry?" if that is the word I am looking for, when I use tap. She always seems to pick up with distilled or dehumidifier water. My other plants don't seem to be to bothered with tap tho, so maybe it is just my Spidey being picky~~ lol.

anyway~~ that is just a "me" thing. :)
Marjie

"Why does some tap water harm plants?"

All tap water (except water treated to remove almost all ions [reverse osmosis]) contains dissolved solids and has the potential to harm plants in time. These dissolved solids are elements like calcium, magnesium, iron, sulfur, sodium, and many others. If you water in small sips and don't flush the soil when you water, or at regular intervals, these elements accumulate in the soil as salts. In the extreme, they have the same effect on plants as curing salt has on meat, actually pulling water from plant cells. As the level of salts builds TOWARD the extreme, it becomes increasingly difficult for the plant to take up water.

Often, the primary reason for impaired root function is an accumulation of solubles in the soil. Often too, root health is impacted by a lack of aeration in the soil due to a high % of fine particles that create compaction, robbing the soil of air spaces and increasing the amount of water the soil holds as saturation. Salt accumulation and compaction/over-watering are usually all part of the same triangle that revolves around a poor soil.

When a plant's ability to easily take up water is compromised, the plant cannot absorb enough water to satisfy the needs of the entire plant. More distal parts, like leaf tips and margins, are left wanting for water and soon dry up from the lack of it.

Boiling water before using it is quite counterproductive. The steam you boil off in the process is deionized - meaning it lacks ANY dissolved solids, so you would be boiling off the most desirable fraction of the water. As the steam reduces the volume of water in the pan(?), all the dissolved solids remain in the residual water, which becomes more & more concentrated (with salts) as more steam escapes.

Al

Not to mention the chlorine, fluoride, and other chemicals intentionally added for our sake. Fluoride is particularly known for causing brown leaf tips, especially on spider plants.

As for the rain, well, I have a custom collection system I made, for really cheap. The end result is a 55g plastic barrel of filtered rain water stored in my basement. Basically, rain collects on an old resin table top I have, and funnels through the umbrella hole, into a rubbermaid tub. At first, I would just transfer the water downstairs, where I have a 5g bucket with a bulkhead fitting through the bottom. I attach a coffee filter the the fitting, which sticks through the lid of the 55g barrel. I simply dumped the water in, it filters through, filling my storage barrel. Last spring though, I got lazy and ran PVC pipe from my 5g filter bucket up and over to the wall, where I drilled through to the outside. I put a valve immediately outside, as well as right at my filter bucket. Now, I just connect a hose from the rubbermaid tub to the barbed fitting stubbed out from the basement, and SHIZAAM! No more carrying water. I just open the valve and let the water drain.

I know it sounds like a bit much, but I can fill half of the 55g barrel with one good, rainy day, or a good hearty downpour. I ALWAYS have at least a half barrel on hand.

Joe

Wonder if bad-tasting water is sulfur water..Yuck, smells and tastes like rotten eggs.

Well, the boiling water concept was only a guess. I figured there'd be drawbacks. :)

Joe, you're lucky you can collect enough rain to water your plants. BTW, how many plants do you have?

Most of my plants are summered outdoors, or were..Don't know if I can anymore due to back/knee problems.

Some plants are set out as early as Apr, most May, brought in late Oct, so 6 months out of the year they're watered w/rain.

Please don't cringe, but there's been times I placed fresh soil directly on soil..lol. I know, I know, doing this is a root-shocker, but so far so good. lol.

I have 15 "houseplants" which includes succulents and tropicals. Most are in gritty mix, and a few are still in 5-1-1, to be put in gritty this summer. I also have 3 bonsai-in-progress trees in gritty mix. If I remember correctly, you have more plants than you can shake a stick at, so you'd need to collect a bit more water than me. The amount of rain water collected depends on the surface area you are collecting from. In my case, the table top is 4 feet, which is ok if we get a lot of rain. However, if I am desperate for more, I just shove the table top halfway under our gazebo, and I get about 10 times the water.

Joe

Hey Folks,

Some great information here, and I also agree that using rain, RO, dehumidifier, AC condensate, distilled or some form of de-mineralized water is great, at least once in a while, for plants in hard water areas. However, just keep in mind that if you *only* use de-mineralized water on a potted plant, and are not keeping up with a well-balanced fertilizer, you will leach out important macro/micro nutrients very quickly, which can leading to arrested growth and deficiencies. Again, this can be dealt with by maintain a good fertilizer schedule.

Regards,

RB