Water type and pH for growing seedlings

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What kind of water do you use to water your seedling transplants and what is its pH level? What is optimal? Seems like there are so many variables that can be.
 

oneeye

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I use rainwater for all my container plants most especially seed germination and seedlings. The best pH for small plants is 6.5 to 7. pH for the best nutrient absorption. Since rainwater absorbs carbonic acid from carbon dioxide the pH is perfect.

Tap water is treated with chemicals, and the pH is altered to keep heavy metals from leaching into the drinking water. Some of the chemicals can harm tiny plant roots.

The other option is to use filtered reverse osmosis water fortified with Cal Mag supplement. Good luck and keep us posted.
 

Meadowlark

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Rainwater here. It is very easy to prove to yourself that it is superior to city water by just running a side-by-side test.

Or you can do a quick search of the 'net "The best water for seedlings is rainwater. Rainwater is nutritious because it contains small amounts of minerals and is slightly acidic ph. Rainwater causes the minerals in the soil to liberate more easily compared to other types of water."
https://www.bing.com/ck/a?!&&p=d6c3...5QjgzQjBFMzI5MzI2NzVCMiZGT1JNPVZBTUdaQw&ntb=1



 
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I just use tap water but, the tap water out here in the high desert of Nevada is basically straight well water. It's barely treated at all! So, the advice above for using rainwater is good, if you are fortunate enough to get rain. In my location, annual precipitation is right at 10 inches per year, on average. So, the rainwater idea, while a good one, just isn't practical here. Also, check your laws! In some locations, collecting rainwater is actually illegal!

As for PH? Yep, something slightly lower than 7.0 is best. I use a combination of methods to lower my PH. I use elemental sulfur in some places where MUCH lower PH is needed. It's a slow process but works for me. If I need to lower PH rapidly and in a limited area, such as watering seedlings would be, I mix vinegar into the water. You MUST be careful when doing that! I keep PH test paper on hand while making my mix. Add a little vinegar to the water, stir it up, test it with the test paper. If the PH is still too high, add a little more vinegar, stir, test. If I have added too much vinegar and the PH is too low, add water to dilute it. This is a quick but TEMPORARY method to adjust PH.
 

Meadowlark

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... Also, check your laws! In some locations, collecting rainwater is actually illegal!
Where specifically would it be illegal to collect rainwater?

And is it limited by amounts...such as even 1 gallon would be illegal?
 

Meadowlark

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Here's a site that lays it out. In Colorado, it's totally illegal. In Utah it's highly restricted.
You must be reading a different law than what you referenced. o_O

It is not "totally" illegal to collect rainwater anywhere in the USA. Two states, however, restrict the amount you can collect Utah and Colorado. There is absolutely no Federal restriction...only two states have antiquated restrictions and both of which currently are in the process of updating those antiquated restrictions.

In Utah the restriction is 2500 gallons per property. However, a permit system is in place for going above that amount.

In Colorado, the restriction is 220 gallons per property. However, in both states Colorado and Utah are in the process of updating their laws to allow for the legal harvesting of rainwater.

The law that is the basis for this ridiculous restriction dates back 120 years when it was feared rainwater collection could possibly adversely affect run off.

The fact that those two states are looking to "modernize" and update their antiquated laws is good news not bad. It tells me they recognize the stupidity of those antiquated laws and the incredible utility in encouraging property owners to collect and use rainwater.

Rainwater is the best for home gardeners.


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