Tuesday
Dec292009

Down in the dirt

Warning: This post is not for the squeamish, because we are going to get down in the dirt. Excuse me, I mean soil. I'm always having to correct myself.

What's the difference between dirt and soil? You can talk about soil at the dinner table. Soil is refined, and it grows vegetables and pretty flowers. Good soil promotes healthy growth in my garden. These are spring photos. On the lower left is the herb bed

Dirt is what's out in the wilds, and it grows good weeds. It gets under our fingernails and invades our homes. It is plebeian and gross, and kids had better wash it off.

Actually, it's all the same stuff. The difference is our attitude.

Soil (I'll be nice) is about 45 percent minerals or tiny pieces of rock, about 5 percent decayed plant and animal matter, and about 25 percent each of water and air. Sandy soil has the largest particles of rock, and water flows through it easily. The rock bits in clay soil are the smallest. When clay is wet, it is sticky; and when it is dry, it is hard (like concrete). It can contain lots of nutrients, but water has a hard time passing through. My pick ax and I know clay soil well, as that is what's in my yard. Loamy soil has medium size rock particles and is the ideal garden soil. Adding compost will improve the soil structure of all soils. 

I talked about compost and soil organisms in my last post, "How I spent my Christmas making mortar". According to Dr. Andrew Moldenke at Oregon State University, "Every time you take a step in an Oregon forest, your foot is being supported on the backs of 16,000 invertebrates held by an average total of 120,000 legs." I imagine something similar is true in an Alabama back yard.

All of these critters spend their lives gobbling up everything in sight, including each other. The food is processed through their systems and then excreted into the surrounding soil. This is an important way organic matter is transformed into minerals that plants can use for nourishment.

Heavy tilling and the use of chemical fertilizers and insecticides disturb the normal underground ecology. Insecticides especially interfere with nitrogen fixation, which is the process by which certain bacteria and fungi transform nitrogen in the air to ammonia, which is a natural fertilizer promoting healthy leaves and good color.

Some lawns are on artificial life support. The chemical lawn company comes in the spring, and the lawn immediately responds with green growth. A couple months later, the grass is looking sickly, so the company returns to spray again. And again. And again. I use a natural fertilizer twice a year, in spring and fall. Green-up takes longer in the spring, but my lawn is thick and healthy throughout the year.This is a summer view of my lawn.

There are many good natural fertilizers, including earthworm compost; seaweed; rabbit, cow, horse, and chicken manure; wood ash and coffee grounds; and composted grass clippings. I also like to use fish emulsion on my herbs and vegetables. It is sad that each year the average family throws away about 1200 pounds of organic matter that could be composted. As gardeners we have a responsibility to care for the earth, for ourselves and for those who come after us, and that includes the world down in the dirt where little worms dwell.

Sunday
Dec272009

How I spent my Christmas making mortar

Christmas at our house this year was a multiple day celebration, beginning with Christmas eve service at our church and ending the evening of the 26th. I felt a deep peace when family and friends came to our home to visit.

 A sunset on Christmas day offered a reflection on the special meaning of this season.

We spent Christmas day with our sons, and then my brother and assorted nephews and nieces and cousins and in-laws came the day after. I was in the kitchen early, peeling potatoes and chopping onions for potato salad. I also was preparing a cranberry salad, a great recipe I got from a fellow blogger, Villager. My family sends special thanks to him. Outside, frost covered the garden.

These knockout roses look like they are covered with a sugary glaze for Christmas.

The frost may kill these leaves, but oh, so sweet, the passing.

These nandina leaves will not be harmed by the frost.

The colors of the nandina are highlighted by an icy coating.

The variegated leaves and lily-of-the-valley flowers of Pieris japonica 'Cavatine' are lovely with winter frosting.

I watched as potato and onion skins piled up. When I was finished, I shoveled them into a stainless steel compost bucket under the kitchen sink. Soon orange, apple and banana peels were added. Then came used tea bags and coffee grounds.  As preparations for our big family meal were completed, I pushed to squash the contents of the compost pail so I could add new ingredients. The bucket was overflowing when I finally emptied it into the larger compost bin we keep behind the house near the vegetable garden. I was happy with the meal we had prepared, and I was happy with the good compost I had brewing behind my house. 

I have been re-reading an old David Bodanis book I own called The Secret Garden: Dawn to Dusk in the Astonishing Hidden World of the Garden. This book describes the incredible microscopic life that exists around us. I recently read a section that explains why compost is the best thing to enrich garden soil.

We hardly ever think about the billions of invisible creatures that live under our feet, but these microscopic critters promote good soil structure, enabling plant roots to grow and obtain nutrients. Basically, the soil dwellers live in underground cities made up of apartment buildings built of tiny clay bricks, and these subterranean dwellings give soil its texture. The bricks are held together by a gummy substance produced by decomposing dead bacteria. Without the mortar of dead bacteria, the apartment homes collapse and the soil becomes hard and compacted.

Compost is good for garden soil because its main ingredient is the gummy mortar used by earth dwellers to shore up the walls of their buildings and to prop open underground passageways. Uncomposted substances like fresh grass clippings are not so good, however, because they contain billions of living bacteria, which promptly go to war with the preexisting occupants of the soil. As the battle rages, nitrogen is burned up and heat radiates from the sweaty, hot warrior bacteria. Nearby plants may overheat and suffer from nitrogen deficiency. It's best to put those grass clippings in the compost pile, and let all the bacteria die off before putting them in the garden.

Ingredients in compost are termed "green" or "brown." Green substances are like those from my kitchen: fresh vegetable and fruit scraps, and also freshly pulled or cut plants from the garden. Brown substances are dried things, like aged grass clippings, shredded paper and dead leaves. The best combination is about four times as much brown as green. Do not put meat products in your compost, unless you want all sorts of critters rummaging through it.

Today I noticed that frost has finally killed the Boston fern in the lady garden. It is headed for the compost bin, where it will eventually turn into mortar to build underground cities.This photo was taken in November. The fern will be replaced next spring.

So, a gazillion bacteria are living and dying in my compost bin right now. Next time I open the bottom door and that rich black mortar mix pours out, I will think about them.

Happy New Year!