To continue from the other thread: Buffers are soil additives to help plants cope with RAPID CHANGE in soil pH, either through fast-drop in pH, as in acidic rain at pH 5.6, or fast-rise in pH, as in too much lime in horse manure, cow manure, or Garden lime. The best buffer overall is neutral pH, slow-to-decompose, and balanced-nutrients. Alfalfa hay fits that bill, but alfafa meal and alfafa pellets ARE NOT good buffers, since they are processed & smaller particles ... these break down quickly, become "sour", thus provide optimal pH for fungal germination.

Too much Garden lime (pH 9) doesn't provide balanced nutrients. Dolomitic lime IS NOT best for multiflora rose with cluster-blooming. Red-lava (high potassium) is a better buffer for cluster-blooming. Alfalfa hay (high nitrogen & plus phosphorus & potassium & calcium) is the best buffer overall. I zapped Baby Fauraux rose (multiflora & cluster-bloom) with calcium via gypsum. Buffering agents against rapid change in pH (be it acidic rain, or very-alkaline topping) ... that depend on a rose' species, and depend on one soil pH.

For many petals-rose like Austin roses, best buffer is equal calcium to potassium, as in alfalfa hay. Second best buffer is high-potassium red-lava rock, at pH 8.2. Third best buffer is cow-manure, but it has to be fluffy, rather than compact. Cow-manure provides phosphorus for deeper-bloom-color.

For French Romantica with dark-green leaves like Sweet Promise, best buffer is alfalfa hay, plus dolomitic lime to buffer acidic rain. Own-root French Romantica prefer it alkaline, same with Dr. Huey-rootstock.

For wimpy own-roots that can't secrete acid, and for stingy bloomers, best buffer is alfalfa hay plus gypsum (calcium sulfate). Gypsum provides the sulfur to release nutrients from soil. Jude the Obscure is a wimpy own-root that prefer loose & loamy soil ... gypsum (neutral pH) helps to break up my clay. Jude HATES dolomitic lime (pH over 9), since the pH is too high. Madame Isaac Pereire is known to be stingy the 1st year. I got my band-size to bloom, with gypsum and alfalfa hay in the planting hole, that rose is 100% clean despite month-long rain, thanks to those 2 buffers.

For cluster-blooming, multiflora rose like Jim's sister-rose-bush, best buffer is alfalfa hay (to help re-grow dropped leaves), plus red-lava-rock (high in potassium, pH 8.2). Heavy-cluster blooming rose is depleted of potassium & phosphorus after a heavy flush. Multiflora does not like dolomitic lime, I already tested that on Baby Fauraux ... it became stunt, stopped growing, and leaves became pale due to high pH (over 9) of dolomitic lime. Cow-manure (high in phosphorus) is a good buffer for cluster-blooming ... that is, if the cow-manure is fluffy like Moo-manure from HomeDepot, rather than dense & compact like New Life manure from Menards.

Dense & compact bagged manure means they put quick-lime to deodorize, quick-lime raises the pH too quickly, thus zapping soil bacteria essential for nitrogen-fixation. I get really BS-prone & short roses, less leaves, but lots of blooms when I use cow manure. Cow manure, like chicken manure has salt, thus best on-top, and in high-rain season.

According to Wikipedia, excessive use of nitrogen and potassium also cause calcium deficiency. In hydroponics experiments, best health for plants is achieved with equal nitrogen to potassium, and 1/2 calcium. That was for SOFT tissue like lettuce and vegetables. But for roses with woody-root like Dr.Huey-rootstock, the calcium supplied should be at equal ratio to nitrogen and potassium.

See an excerpt from below link: "Acidic, sandy, or coarse soils often contain less calcium. Uneven soil moisture and overuse of fertilizers can also cause calcium deficiency. At times, even with sufficient calcium in the soil, it can be in an insoluble form and is then unusable by the plant or it could be attributed to a "transport protein".[2] Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium ... Soil pH should be tested, and corrected if needed, because calcium deficiency is often associated with low pH.[ .... "Calcium deficiency symptoms appear initially as localized tissue necrosis leading to stunted plant growth, necrotic leaf margins on young leaves or curling of the leaves, and eventual death of terminal buds and root tips."

https://en.wikipedia.org/wiki/Calcium_deficiency_(plant_disorder

There are many different types of lime. The slow-released type is best: dolomitic lime (has calcium & magnesium), and granular lime. The fast-released types are NOT best for plants, since they raise the pH too quickly, such as pelletized lime, quick lime, and hydrated lime (very caustic). Hydrated lime is used by municipals to treat tap-water, thus making tap-water alkaline. I went to HomeDepot, and they sell 2 types of sand for Paver-base: The yellowish COARSE sand, which doesn't break down and is great to break-up clay, and the limestone chips (whitish). See below:

considerwhy

I've seen the responses that suggest we use limestone chips instead of powdered or granular limestone, to buffer acidic soil. I went to garden centers, Home Depot, Lowes, and mulch/stone centers and none of these places knew what I was talking about. But all of these places sell bags of small, white, dusty, "marble chips". I tested these marble chips and I believe these are actually limestone chips. If you drop these chips into vinegar, the chips effervesce and do neutralize the acid. So the chips labeled as "marble chips" will buffer acidic soils"

http://forums.gardenweb.com/discussions/1887991/lime-granular-or-pelletized?n=4

Just a note that lime (calcium) should be used together with nitrogen. Hydroponics site stated that calcium should be 1/2 of nitrogen and potassium. My best result in this year's constant rain is to supply gritty lime together with chicken manure for nitrogen, plus red-lava-rock for potassium. Equal nitrogen to potassium, 1/2 phosphorus, and 1/2 calcium is the best ratio for optimal health. Below is Crown Princess Magareta, 100% clean, on its 2nd flush, picture taken today, July 15, after weeks of extreme humidity and drizzling rain:

There's many studies that show how re-mineralization helps with forest growth and increase yield of corn. Minerals act as buffers to neutralize the acidic rain, plus provide structure and nutrients for roses to re-grow leaves. Here's an excerpt from Wikipedia on rock dust: "The igneous rocks basalt and granite often contain the highest mineral content, whereas limestone, considered inferior in this consideration, is often deficient in the majority of essential macro-compounds, trace elements, and micronutrients.

Soil remineralization creates fertile soils by returning minerals to the soil which have been lost by erosion, leaching, and or over-farming. ... Volcanoes erupt, spewing forth minerals from deep within the Earth, and rushing rivers form mineral-rich alluvial deposits.

Rock dust is added to soil to improve fertility and has been tested since 1993 at the Sustainable Ecological Earth Regeneration Centre. SEER's research claims that the benefits of adding rockdust to soil include increased moisture-holding properties in the soil, improved cation exchange capacity and better soil structure and drainage. Rockdust also provides calcium, iron, magnesium, phosphorus and potassium, plus trace elements and micronutrients. By replacing these leached minerals it is claimed that soil health is increased and that this produces healthier plants.

The calcium and magnesium in high quality have the ability to neutralise pH in soils, in effect acting as a liming agent."

Below is a testimony to the effect of rock dust via Azomite on trees and tomatoes: http://www.underwoodgardens.com/soil-building/mineral-restoration-of-your-garden-soil/

"Two sources are readily available and usable for the home gardener to restore the minerals to the soil. One is sea minerals, the other is volcanic rock dust. My concern with using sea minerals for the home gardener is the salt content, and the potential damaging impacts that salt might have. The second source- volcanic rock dust has no salt and is composed entirely of minerals. This article introduces volcanic rock dust in a product known as Azomite. ..."

**** From StrawChicago: I think Azomite (rock-dust) is over-hyped & expensive. River pebbles are sold cheap for $2 per big bag at Menards. My neighbor put river pebbles AT THE BOTTOM of the planting hole in a soaking wet clay area, and her roses are blooming great & retain all their leaves in these 2 months of constant rain.

I'll include some links of rock-dust and granite dust on Amazon in case someone want to test them:

Five pounds of glacial rock dust for $15 on amazon:

http://www.amazon.com/Natures-Footprint-Glacial-amendment-5-Pound/dp/B008YSVPHC/ref=cm_cr_pr_product_top?ie=UTF8

Five pounds of azomite for $8.92 on Amazon. I'll get that just to test on the roses near trees (where minerals are depleted).

http://www.amazon.com/Pounds-Azomite-Organic-Essential-Minerals/dp/B00AJALC2G/ref=cm_cr_pr_sims_t/180-3258193-8004869

My high-magnesium clay is already rich in minerals to the point of being rock-hard .. but near the trees & in high-rain period, I still need to add clay on top to re-mineralize, and to prevent roses from breaking out in black spots from potassium & mineral-erosion due to acid rain.

atlantic_door posted this on June 16, 2012: "My wife has some health problems, so I placed some containers right outside of our garage so she could work with them easily. I added azomite and some earthworms to the potting mix this year and the plants have done incredibly well. The picture is from June 10th, still very early in the season." atlantic_door

From StrawChicago: Atlanta_door's picture shows vibrant color, deep-green. After my visits to Chicago Botanical garden with 5,000 roses ...and seeing how faded & bleached out the color of some roses ... I'm going to test Azomite to see if that deepens the color of blooms, also if it's effective as a buffer against acidic rain. Below link shows the many trace elements of Azomite.

http://www.azomite.com/resources/coa.pdf

Good luck with your testing of Azomite Straw! I'm not familiar at all with that term...

Wonder what these people used to feed the Earthworms in the pots? Potted soil gets so hot you would think it would cook the earthworms? That's why I've never tried it...

Interesting about the mineralization --- I don't want to deal with dust too much because I am not the safest when it comes to applying things, I don't want to inhale anything so either prefer as granular or as soluble.

Look forward to your test!

Re-posting what I posted on the other thread:

Folks report that Azomite helps to deter pests, it thickens the tissue of plants. Molasses work very well in deepening the blooms' color, but I'm afraid to use it, for fear that would attract pests like rose-slugs.

When to use gypsum (calcium sulfate) and when to use dolomitic lime (calcium & magnesium) ? I narrow down to:

1. If the rose blooms profusely, means it's good in acid-phosphatase, and will have excess acid at end-bloom-period. Time for dolomitic lime during profuse-blooming.
2. If the rose is stingy, means it doesn't secrete enough acid to release phosphorus from soil. Time for SOLUBLE gypsum (calcium sulfate, with 17% sulfur). The acid, or sulfur helps to release phosphorus from soil for blooming. The mycorrhyzal fungi that help plants to bloom also prefer slightly acidic. Some disease-resistant roses fall into this category (Home Run, Basyes Blueberry, Duchess de Rohan, some Kordes roses). Folks in alkaline CA complain about Kordes being huge & healthy foliage, but stingy in blooms. Never see a black spot on B.B, but it's stingy unless given soluble fertilizer. Home Run is filled with dark-green foliage, but few blooms. I would rather get the disease-resistance from thick & shiny foliage (FlowerCarpet), than stinginess in blooms (Home Run).
3. If the rose is wimpy, SOLUBLE gypsum and sulfate of potash help.

Buffers are alkaline stuff put on top to neutralize acidic rain. Horticultural sites listed calcium, potassium, magnesium, slow-released organic matter as good buffers. Alfalfa hay is a good buffer (neutral pH, slow-to-break down), same with pine-needles. But alfalfa meal is a poor buffer: breaks down too fast, and releases acids. Cedar-mulch is a good buffer (slow-to-break-down). Pine bark mulch is a poor buffer (acidic pH at 4). Penn State research on artillery fungus cited BIG CHUNKS & SLOW-TO-BREAK down mulch as best. Red-lava-rock is an excellent buffer (pH 8) & slow to break down.

I spent $10 on a tiny bag of crushed-red-lava-rock, ordered from Amazon, and it WASN'T AS GOOD as the cheap $4 per 40 lb. bag big chunks. The crushed-red-lava broke down too fast, and stained the leaves of Stephen big Purple with its high iron-content.

In contrast, I get continuous blooming on Wise Portia this year thanks to big-chunks red-lava-on top (for potassium), plus dolomitic lime (calcium & magnesium) .. lots of leaves thanks to neutral alfalfa hay on top. Nature's way is best: For centuries big-chunks stuff fall onto roses or occur naturally in soil: leaves, branches, rocks, etc..

Centuries ago, people didn't have wood-chipper to grind bark into pieces, or trucks to carry inappropriate mulch (pine-bark) onto roses. Chicago Botanical Garden made a good point of mulching plant WITH THE SAME optimal pH range for that plant. So it doesn't make sense to mulch Dr. Huey-rootstock with acidic pine (pH 4), or to mulch blueberries with horse manure (pH over 8, with lime added).

Thanks for the info Straw!