Showing posts with label soil. Show all posts
Showing posts with label soil. Show all posts

Saturday, March 05, 2011

March on the Paths

March is the month I love my garden paths the most.

I have a long list of things to do in the garden from March through May – cleanup leaves, branches, dried plants; prune the crepe myrtle, pussy willow, euonymus, japonica, roses; divide liriope, black-eyed susan, phlox, daylilies, mums. Soon there will be mulch to spread and weeds to pull followed by deadheading and planting. As the snow melts, the temptation get on with the job is overwhelming.

But the ground is soft and spongy

Good soil consists of 45% mineral materials and 5% living and dead organic materials and 50% pore space for air and water. All are necessary for good plant growth. Damp soils compact easily, squeezing out air and water. Roots have trouble growing and taking up nutrients. I try not to walk on the spongy soil (or on the sleeping perennials hidden under the soil).

This is when I really I appreciate the paths in the garden. I can reach a lot from the paths. Some paths are for wandering from place to place but almost every garden that is wider than 4 feet has a path for maintenance. That way I can keep my big feet out of the garden and march on the paths.

More information from the University of Delaware Cooperative Extension “Combating Soil Compaction.” (PDF)


Saturday, April 04, 2009


Marvelous spring weather between rainy days, gave me a chance to spread compost this week.

I have a small compost bin and a pile of shredded leaves.

I removed the top layer of un-composted material from the bin. Then I shoveled the beautiful black gold into a wheelbarrow and spread it around the lilac/shade garden and pussy willow/sun garden.

When the spreading was done, I put the top layer of un-composted material back in the compost bin to start another pile. I’ll add kitchen scraps, garden waste, and coffee grounds throughout the summer. Last fall’s shredded leaves will be added when I need “brown” material. I’ll turn it with a pitch fork from time to time. I’ll add water when it looks dry.

Five wheelbarrows of compost didn’t go far. I’ll spread mulch next week. I put mulch and compost on the garden every year. The mulch also decomposes and improves the soil making it dark and loamy. I have reduced the need for fertilizer.

The plants are happy. The gardener is happy.

(Planet Natural’s “Composting 101” contains a lot of information on composting. This site also has organic supplies for sale. I have never ordered from them. If you have placed an order with Planet Natural, please comment and share your experience. )

Saturday, October 11, 2008

Shade Garden

My shade garden is mediocre at best. Under a French lilac in front of 70 ft. hemlocks, the hostas get smaller each year. Asters, silver mound, mums and numerous annuals have met their demise. Planting bulbs is as bad as digging through a tangle of bureaucracy. The root mass is quite thick. The daffodils, columbine and Japanese anemone seem to hold their own. Astilbe survives in a low spot that gets a little more water.

Two years ago I started thinking seriously about this garden. Did I want a garden survive or thrive? This happened the same year that I decided to be more environmentally aware. I have never used a lot of chemical fertilizers, pesticides or herbicides. I decided to use even less or none. The plants would have to survive or thrive on their own with only organic methods. I have soaker hoses in all the beds. They were not turned on this year.

I did a soil test in the shade garden last fall. pH is near optimum neutral at 6.8. The soil is below optimum in phosphate and potash and way above optimum in magnesium and calcium. I admit I added phosphate and potash. I easily slipped back into my “only a little” mode. I don’t know if I would do that today and risk chemicals washing into streams.

Then, in a V8 moment, I started doing what my grandmother knew to be right - if you want a good garden, improve the soil. I’ve added mulch twice each year. I’ve sprinkled compost tea in the area several times. My only fertilizer is fish emulsion. I’ll add compost in spring. This is an ongoing, never-ending job.

I have had the privilege of reading a preview of Doug Green’s “Shade Gardening” ebook. It is a clear, succinct and no-holds-barred book about what it takes to have a thriving shade garden – good soil, light, water.

Now I have to decide how much I want to fight Mother Nature. Plants need light (even in a shade garden), good soil and water. None of these is readily available under most trees. I believe there is enough light under the lilac for shade plants. I’m doing my best to improve the soil.

But, by Doug’s calculations, I will need about 3 inches of water a week. I’m not sure that I’m willing to do that. I may have to let this garden just survive.

Wednesday, April 16, 2008


The other night I watched Jean-Michel Cousteau: Ocean Adventures Return to the Amazon” on PBS. I was amazed to hear about “Terra Preta de Indio (Amazonian Dark Earths)” currently called biochar or agrichar.

According to Dr. Johannes Lehmann of Cornell University Assistant Professor, Soil Fertility Management, Department of Crop and Soil Sciences:
"Soils with biochar additions are typically more fertile, produce more and better crops for a longer period of time."
From Cornell ChronicleOnline by Susan Lang (Dr. Lehmann) “shows how reproducing the Amazon's black soil could increase fertility and reduce global warming."

If biochar is some sort of miracle soil amendment, why have I never even heard of it? Have you?

Originally, Terra Preto was made by pre-Columbian Indians in the Amazon River Basin. Most information points to a society that burned trees to make room for agriculture then added agricultural waste, human and animal waste, broken pots and refuse in a sort of an agricultural garbage dump.

As I understand it, biochar can reduce the need for fertilizers, reduce greenhouse gasses. “Char-amended soils have shown 50 - 80 percent reductions in nitrous oxide emissions, increase crop yield as well as supply a renewable energy source" (International Biochar Initiative [IBI]). According to IBI, “The bio-char process . . . produces a combination of both bio-energy and carbon-sequestering fertilizer from agricultural waste, which results in a net reduction of carbon dioxide (CO2) from the atmosphere.”

Today, biochar is manufactured by slow pyrolysis. According to Best Energies in their work on clean energy production:

“Slow pyrolysis is a thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen. The feed material is dried and fed into a stirred, heated kiln. As the material passes through the kiln, a combustible synthesis gas (syngas) is evolved and is continuously removed from the kiln. Approximately 35% by weight of the dry feed material is converted to a high-carbon char material that is collected on the discharge of the kiln.”

An easier to understand article was published September 1, 2007 Environmental Science & Technology published by the American Chemical Society:

"Pyrolysis, a technologically advanced form of smoldering, involves burning biomass under controlled, low-oxygen conditions. Small- and large-scale facilities work in various ways and yield a variety of energy products, including bio-oils and gases, with biochar as a byproduct."

OK, let’s just say heating in the absence of air.

There is definite interest in biochar research and production worldwide. The International Biochar Initiative (IBI) was formed in 2006. In 2007, IBI held a conference in Australia. It attracted science & business professionals from around the world. The 2008 conference will be held September 8-10, 2008 in the UK.

Democratic Senator Ken Salazar of Colorado introduced S.1884 – The Salazar Harvesting Energy Act of 2007. A Summary of Biochar Provisions in S.1884: Carbon-Negative Biomass Energy and Soil Quality Initiative for the 2007 Farm Bill is published here The bill will boost funding for biochar research.

There are many unanswered questions:

Who will conduct research into the possible negative environmental effects?

Who will regulate or measure manufacturing methods and quality (how)?

Will modern biochar be able to reproduce the sustainability of benefits to the soil that was established in pre-Columbian soils?

What system is best to mass produce biochar?

Will biochar contain enough inorganic ions, such as phosphorus and nitrogen, essential to plant growth?

What is the best raw material to use? How will it be collected?

Who will develop distribution machinery for farmers to use to spread biochar on crop fields? Will it be affordable?

There is a lot of work to be done but I suspect we’ll be hearing more about biochar in the future.