Carnivorous Plants/Distilled water
QUESTION: Hi sarracenia northwest, I grow couple of Venus flytraps and a sarracenia purpurea in peat and are exposed to 8 hours of direct sunlight. I had been growing them for about a year and are healthy. My question is on the water. I make my own distilled water by boiling tap water for 10 minutes and that is it.I checked on the computer how to make distilled and it is completely different from my way. Is this water okay for my carnivorous plants?
ANSWER: Hi Jacobo,
Here's the deal with this. This is an old urban legend that boiling water removes minerals. It doesn't. If anything it concentrates them. The only way to get the minerals out is to turn the water into steam, then re-condense the steam into water. That's what distillation is. The other two methods that will remove minerals are reverse osmosis, and ion exchange. Reverse osmosis works by forcing water through a special membrane with pores large enough to let water molecules pass, the not the larger mineral molecules. Ion exchange works by having a particular catalyst material that causes the minerals to stick to it. Examples of this are Zero Water filters. Nothing else removes minerals no matter what you may have heard.
The bottom line is that there is no super cheap easy way to remove minerals from water that cause problems for carnivorous plants. If your tapwater has a high mineral content rainwater is the lowest cost, but not helpful in dry climates. Reverse osmosis is the most cost effective, but the units are expensive. Zero Water is fairly inexpensive, but if your water is really hard, you'll be replacing filters frequently, and their not cheap. Distillation is very reliable, and units are not that expensive, but because of the electricity they use they cost more to operate. Hope this helps.
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QUESTION: Its Jacobo again. Like I said, I've been growing my carnivorous plants for a year and there are very healthy. Could I just re-change the soil every year to prevent accumulation of minerals in the soil? And how would I know if my tapwater is high in mineral content. I live in Fontana CA.Thank you.
It's quite possible that your water isn't all that high in minerals. Often if cities get their water from surface sources like rivers, especially if the rivers originate in nearby mountain ranges, they tend to have a low mineral content. Sometimes the type of mineral content can make a difference too. Calcium and magnesium tend to be the biggest offenders with carnivorous plants. Iron doesn't seem to bother them as much.
My personal experience with this has been where we live. Where we have the nursery now in Eagle Creek, OR we are on a well, and we do see mineral build-up after a time on faucets in our house. The deposits are white, so it's mostly calcium and magnesium. Our first year here we lost close to half of our Venus Flytraps from hard water damage, and they do tend to be the most sensitive to hard water. Sarracenia take much longer to show damage, but we saw plenty in the form of browning lids on many plants. We now pass our water through reverse osmosis units for the nursery. Now my father used to live about a mile from us, and his well was mostly high in iron; lots of red deposits on sinks and fixtures in the house. He had some cp there, but they were not affected that much.
So, changing the soil will definitely help if you're showing some hard water damage on plants, but testing your water will give you an idea of what you have. One simple way to do this is to go buy a ZeroWater pitcher. They come with a TDS (Total Dissolved Solids) meter. If your water is 50ppm or less you are probably fine. Just use rainwater when you can, or purified water. The ZeroWater is great at removing minerals, but only practical for smaller quantities of water. We use one for houseplants just because it's easy for indoor use. Other ways you can test the water is to take a sample to an aquarium store, or buy a test kit or meter. Also, here's a link to your water department in Fontana, and their quality reports: http://www.fontanawater.com/water.php?id_pge=15