Tuesday, April 20, 2010

Something we can all agree on...COMPOST

Yes we can, agree.
Great pontification, dear readers reader! Decomposable compost is great for the soil, beyond just  soil structure improvements.  It does more than provide food for the soil microorganisms that help aid in aggregating soil.  Let us draw our attention to the mother of all soil amendments (please think out loud in a bellowing voice),  Compost!

  • It increases cation exchange capacity, 
  • improves structure, 
  • helps retain moisture, 
  • and provides nutrients! 
  • It can almost do no wrong!
As an aside, you can use manure to make your garden compost.  I am trying to help a friend learn about the nutrient profile of elephant and donkey poop manure for her bipartisan victory garden.  Ideas on where to find that info?

Here are some interesting links I found during my, so far unfruitful, search.

What do bees have to do with soil?

What is a picture of a flower doing on a soil blog? I'll tell you!  I'm hoping that by letting my collard greens flower out, and get taller and taller and taller, that the roots will get deeper and deeper and deeper.  I'm hoping that these roots will help improve the sad soil structure of my villainous vertisol.  Now, I didn't ask a real soil scientist if this would work.  I'm just guessing based on what I've read here (Reference #1).  So why do I think this will help my plants down the line?  Let's read bullet points!

  • Soil texture*  and soil structure* determine the ability for a soil to hold and conduct the air and water that plants and soil animals need.
  • Vertisols (high clay) are known to be massive* under wet conditions.
  • My clayey soil, with no structure (massive), might not have enough structure to allow proper drainage and aeration. 
  • One step in getting good structure is getting some good macropores* going.  They will allow space for roots to grow and to allow for flow of water and air.
  • Macropores can be made by roots and other living organisms, they are called biopores.
  • Other things help structure too:
    • Minimizing tillage, 
    • timing your soil traffic on drier days (don't crush those precious soil peds), 
    • mulching, 
    • adding organic matter to promote microbial decomposition, 
    • using cover crops or rotating crops which promote root growth, and
    • adding gypsum or other soil conditioners (works best in irrigated soils).
I wish you the best of luck with your soil structure!

Soil texture: the relative proportions soil particle sizes (e.g. sand, silt, and clay)
Soil structure: the arrangement of soil particles into larger units, or peds.  Link to examples
massive: No visible structure, or aggregation of soil particles.
macropores:  Soil pores large enough to allow water to drain readily by gravity.  They generally have a diameter larger than 6 mm.  You can consider this useful void space.
biopores: Large soil pores that were made by roots, earthworms or another soil organism.

Wednesday, April 7, 2010

What are cations, why do I care.

Soil is so interesting, it makes me want to stare into space.
What are cations? 
They are ions that carry a positive charge of electricity (Reference 4). The common soil cations are calcium (Ca+2), potassium (K+), magnesium (Mg+2), sodium (Na+), and hydrogen (H+) (What is an ion, you ask.  An atom or molecule that has lost or gained a charge -by losing or gaining an electron).
Why do we care?
Many of these cations are nutrients for plants.  Different soils have a different capability to hold these nutrients (and other non-nutrients e.g. aluminum Al+3) and store them. This is quantified by cation exchange capacity.  The higher the exchange capacity, the less likely your favored cations will leach away from your beloved plant roots (and in tangential news, the lower your "base saturation", the less likely the mineral will give that cation up and let it go into the soil water solution for roots.  What is base saturation? I'll get back to you with an eloquent reminder, just... remind me).

Monday, April 5, 2010

The Joys and Turmoils of the Yard Bird

Chickens provide many benefits and obstacles to the garden.  Here are some examples-
  • Their healthier, yellower yolks from eating greens (&bugs?) in your garden (omega-3s & carotenoids, etcetera, baby!), but be careful they don't compete for foods you intend for yourself!  
  • They make high nitrogen (nutrient) compost, but be careful it is "aged" properly or it will burn your plants or contribute disease to the soil.  Spreading it thin by always providing them fresh yard prevents some issues.
  • They are good surface tillers, and their "tilling" is less likely to hurt your soil structure; but they are SO good, given the chance, they'll get everything;
  • Pest eradicators.  They are equal opportunity hunters, so they will assassinate garden friends and foes- be careful!