Re: CULT: Irrigation vs. rain
- To: Multiple recipients of list <i*@rt66.com>
- Subject: Re: CULT: Irrigation vs. rain
- From: J* <J*@Rain-Garden.com>
- Date: Mon, 10 Nov 1997 20:40:03 -0700 (MST)
We notice that rain water is magical here in coastal southeastern US
too.
Our water comes from a well and is not chlorinated of otherwise
treated. The well is bored into a limestone aquifer so the water has a
pH of about 7.7 with considerable buffering capacity. While we get over
a meter of rain annually and precipitation exceeds evaporation, there
are dry spells. This presents a dilemma for iris, camellia, centipede
turf, etc. which may hate the alkaline irrigation a much as the drought.
Our rain, on the other hand is acidic (yes, acid rain). The pH of rain
may be as low as 5.2. The thing that amazed me the most was not the
acidity, but the ammonia content of our rain water. I recall one shower
with an ammonia nitrogen concentration of 4.5 ppm! Most rain clouds
approach from the west, but the few rain cells which develop over the
ocean and move onshore seem to have much lower ammonia and more neutral
pH.
I believe the ammonia can be used directly by many plants to some extent
and is quickly converted to nitrite and nitrate by nitrifying bacteria
in the soil.
Ain't pollution wonderful.
John Hopkins
South Carolina - zn 8b
> John Montgomery wrote:
>> [snip]
>> Now I have a question. I am certain that the plants grow much better
>> after a heavy rain than they do following a similar amount of
>> irrigation water being applied. Am I imagining this or have others
>> noticed a similar result? For what it is worth, our irrigation and
>> domestic water are delivered in the same pipe and during the hot part
>> of the summer it is very heavily chlorinated - to the extent that we
>> buy bottled water for drinking. Can this have anything to do with it?
> I've been aware of this phenom & always assumed that it's due to my own
> miserly ways when watering with a hose. Thing is, my water comes from
> our well -- no chlorine. The well water is very hard tho -- the local
> wit has always advised 'chew your water well'.
> Bill Shear's mention of lightning converting nitrogen in the air into
> soluble nitrates intrigued me as we get a great deal of lightning along
> the Front Range in Colo., so much that there's some kind of national
> weather group that studies it here. Maybe this does contribute to plants
> showing more liveliness following natural rainfall than they ever do
> from being irrigated -- interesting!
> 'Nother thing -- garden writers often tell us not to wet the leaves of
> certain plants when watering as it's detrimental to good health yet
> these same plants seem to thrive after a good rain-drenching, even if
> the leaves do get mud-splashed. Odd.
