help needed

[Medbury Gardens]

We can buy bone flour here,but its not cheap so would cost a fortune considering the size of my garden area.
I plan to buy 100kg of dolomite lime tomorrow and dress the orchard area as well.

[dice]

The things to watch out for as you raise pH between 6.0 and
7.2 are induced defiencies of trace elements manganese,
Copper, Zinc, and Iron. Above 7.2, you start to see issues with
phosphorus tie-up, etc.

Shortages of calcium and magnesium have drastic effects on
yield, though, so if you need those you do, and if adding them
raises pH too far, then that will need to be adjusted as a
seperate issue.

This document has a discussion of pH and the effects of
aluminum at various pH levels on the uptake of major and
minor nutrients:
http://hubcap.clemson.edu/~blpprt/acid2.html

The availability of Mn, Cu, Zn, and Fe to plants generally decreases as the soil pH increases. Liming soils that are inherently low in these elements may induce micronutrient deficiencies for a short or long time.

So, you may find that other deficiencies show up after adding
dolomite to supply calcium and magnesium or not, depending
on how much the pH is raised, what is already in the soil, what
you add with various organic inputs, etc.

[Medbury Gardens]

Originally Posted by dice

The things to watch out for as you raise pH between 6.0 and
7.2 are induced defiencies of trace elements manganese,
Copper, Zinc, and Iron. Above 7.2, you start to see issues with
phosphorus tie-up, etc.

Shortages of calcium and magnesium have drastic effects on
yield, though, so if you need those you do, and if adding them
raises pH too far, then that will need to be adjusted as a
seperate issue.

This document has a discussion of pH and the effects of
aluminum at various pH levels on the uptake of major and
minor nutrients:
http://hubcap.clemson.edu/~blpprt/acid2.html



So, you may find that other deficiencies show up after adding
dolomite to supply calcium and magnesium or not, depending
on how much the pH is raised, what is already in the soil, what
you add with various organic inputs, etc.

That's the interesting thing, even though the calcium and magnesium levels are low ive still been getting excellent yields

[ireilly]

But you'll note that your ratio is close to the 7:1 ratio they mention.

And they are below those minimums they list, but remember the soil properties affect bioavailability of nutrients because of leaching propensities, ion transport, etc. Another way to say this is that a sandy soil may have different recommendations than a highly clayey soil.

Thus fortyone's recommendations to essentially nurture the microlife in the soil and let it balance things out, with occasional help.

IOW, if it ain't broke, don't fix it. I'm a big worm fan myself.

Walter

[wmontanez]

More to read, this goes into details of each element and explanation of the chemistry in the soil. There are more fact sheets in the links at the bottom.

http://www.umassvegetable.org/soil_c...basics_II.html
http://www.umassvegetable.org/soil_c...basics_IV.html

[dice]

[Re: dolomite vs gypsum+magnesium]

Thinking more about this, dolomite is probably the better
choice despite raising pH because the calcium and magnesium
in it become available at the same rate. Gypsum releases
calcium at about the same rate as lime of the same fineness
(same mesh), but magnesium sulfate (epsom salts) dissolves
quickly, and the magnesium is immediately available. The
magnesium in chelated magnesium products is likely available
immediately, too.

You have some room before pH gets high enough to be a
problem in itself. If your soil pH were 7 or higher, a different
choice of calcium and magnesium sources might be indicated.

[Medbury Gardens]

I couldn't imagine that one application of dolomite would push the PH over 7 from 6.4 would it?.
Also dolomite is quarried locally so its relatively cheap at $NZ 13 per 10kg bag which works out at about $US11,how does that compare for you guys??

[dice]

I got 50 lbs for $9US recently. It was a powdered form.
I routinely find it granulated for $6US for 25 lbs at big box
hardware stores with garden supplies.

I add some gypsum every year. Calcium is not as mobile in the
soil as magnesium sulfate or chelated magnesium or nitrogen,
but there is some loss each year from our extensive rain. My
pH levels are above 6.5 now, so I have stopped adding dolomite
until it drops below there.

One vendor here that markets big bags of magnesium sulfate
(epsom salt) said it should be side-dressed on top of the soil
rather than broadcast so that leaching from rainfall and irrigation does not wash it out of the soil before roots can
reach it.

[Medbury Gardens]

Wow that is a lot cheaper than ours.

I wouldn't have the same amount of leaching from rainfall as our annual rainfall is 500mm 20in,90% of that falls in winter,how much do you get dice?

[dice]

Avg rainfall here is 43.71 in, (1110+ mm). That matters. You
will not likely lose nutrients that leach out of the soil as fast
as we do. What kind of soil matters, too. Nutrients leach out
more slowly in clay and soils high in organic matter than in
sandy soils (more binding sites for nutrient ions).

[wingnut]

We bury all the bones from our rabbits& chickens, as well as all the carcasses from my winter trapline in the garden.I also tote and compost all the undergrowth from my surroundinfg woodland, add rabbit, chicken, and whatever else I can add. Almost forgot, alot of fish heads/bones/guts go in also.