Showing posts from June, 2016

I'll Take Biochar Dressing on the Side

In addition to top-dressing, side-dressing with biochar looks like a labor-saving method of application. Not only is it easier, but the resulting black mulch will enhance the appearance of gardens like mine. I've been using free shredded wood mulch on the paths between my garden beds. With cardboard underneath, a thick mulch layer helps keep weeds to a minimum and feeds the underlying soil as it breaks down. The same can be said of biochar, but there are several additional advantages. (1) Biochar will last much longer than decayed wood chips. (2) Walking paths suffer from compaction, making them less hospitable to roots. Walking on the biochar grinds it down. Biochar particles contain pore space that will compensate for compaction, aerating the soil as they are leached in over time. Paths that are less compacted (containing more air) are more inviting to roots and mycelia. If the roots don't reach that far, mycorrhizae can perform their horizontal drilling trick, expanding the…

Sunshine Insurance

Composting biochar and digging it into the soil before planting is a best practice that needn't be followed in all situations. When mulch is needed, especially for warmth-loving plants, biochar could be a better choice than straw or other common dressings. As I pointed out in my previous post, this mimicking of a natural fire's residue gives the biochar an opportunity to become somewhat charged and inoculated while holding moisture in the ground.

Plants need three things to exist: Nutrients, Water, and a suitable atmosphere that contains Light. Charging biochar with nutrients and getting it wet make it an excellent buffer for the first two needs. For the sake of completeness, I've been trying to imagine how biochar could also buffer a plant's need for light, allowing it to make sugar without total reliance on photosynthesis. If it does this, it would be by use of an alternative energy source, e.g. electric current.

The discharge of electrical currents around plants is …

Making Biochar, Rain or Shine

My small scale biochar production cycle is weather-driven. When rain is infrequent, I make char while the sun shines and pour out the new biochar into a framed area dubbed my "biochar patch." Quite a bit can accumulate before rain comes to rinse the biochar and fill up its macropores, making it ready for the next step. I like to allow no more than a day to pass after a good rain before I crush the moistened biochar with a tamper and screen it through a salvaged patio tabletop into a bin. Dry biochar makes too much hazardous dust when crushing and sifting, so rain is welcome, though a couple of dry days are then needed for my feedstock to dry again. This gives me time to split more wood in preparation for the next round. 

The admittedly tedious process of sifting biochar by hand has the advantage that any remaining torrefied pieces can be culled and sent back for more charring. Torrefied wood, i.e. pieces not charred completely through, inhibits plant growth, and does not bel…

Making Ponds out of Parking Lots

In the Chesapeake Bay watershed, climate change will make cleanup efforts more challenging because, aside from the storm surges and shoreline damage from the rising sea level, runoff will increase with the greater amount of precipitation predicted in the cooler half of the year. Rain barrels can help only so much, due to their limited volume, but a pond could capture much more water, depending on how it is fed and drained.

Most garden ponds aren't designed with stormwater management in mind, but by allowing water to be partially drained in dry spells and filled up by storms, the pond would function much as a rain barrel does in supplying water to other parts of the landscape and saving on the water bill.

I hate to see all the extra free water from above wasted, so I am considering converting part of our overly large, increasingly obsolete driveway to a segmented pond that would provide a cool and sedate point of entry to our home.  It could be fed by rain barrel overflow, a shed r…

Geoengineering Your Garden

When life gives you liminality, make lemons or some other subtropical (or even tropical) fruit. For us here in hardiness zone 7, climate change will probably have us in zone 8 in a decade. My palm trees and peaches will feel right at home. To grow citrus or bananas, however, a little geoengineering will be needed by way of tweaking areas of our property where the microclimate can be pushed a bit further in the warm and humid direction. In Paradise Lot+Eric Toensmeier and +Jonathan Bates offer many suggestions on expanding your hardiness zone.

Raingardens, ponds, and swales all contribute to higher ground-level humidity. Our future hops vines, growing at a angle to a height of 35 feet should also create a quasi-greenhouse beneath, especially with the compost pit dug into the ground near their base. We also want to leverage warm, sunny spots created by South-facing walls as good areas to tropicalize.

And for that, we have a secret ingredient. Biochar, with its low reflectivity, is a …

Your Own Little Rainforests

Lawns do a fair job of capturing runoff, but just putting an average-sized house on a lot can double the amount of runoff from that property. Much of that increase is channeled to gutters and then downspouts, at which point an owner can take a number of further measures to reduce problems downstream. Outlets from downspouts, be they splash blocks or French drains will often evince erosion where the water is let loose to run freely on the soil. This is the place to intervene with a rain barrel and/or a swale. These may still lead to erosion wherever the water discharges, so a garden can be added to infiltrate the excess.

By concentrating the captured runoff, areas of Maryland properties typically receiving 44 inches of rainfall per year can easily get double that amount, making them like miniature rainforests.  Forest gardens are very good absorbers of groundwater, as are rain gardens.

One of my rain barrels discharges through a 25 foot garden hose into a French drain which discharges …

Char Your Lawn

Of the nutrients that pollute the Chesapeake Bay lately, phosphorus has been the worst. "Why, of course, with all those chicken factory farms on the eastern shore," might be one's reaction to this statement. In fact, the major phosphorus inputs are coming from tributaries on the western shore of the Chesapeake. The cause has not been identified, but it could well be leaching from residential yards. Maryland soils are generally high in phosphorus, so soil disturbances by developers could also play a role.

In 2012, Maryland passed a law that prohibits the use of phosphorus on lawns except for one-time applications in cases of repairing patches, establishing a new lawn, renovating an entire lawn, or if a soil test shows a deficiency. As the phosphorus gets used up over the years, lawns will then suffer, more soil testing will be needed, and more phosphorus. Biochar can help here. Along with its many other soil enhancing benefits, biochar is very good at adsorbing phosphorus…


Weeds like cypress spurge can establish themselves where nutrients are scarce, but most horticultural plants require more care and feeding in order to grow to their full potential. Nitrogen is the macronutrient in highest demand by vegetables, requiring most gardeners to supplement their soils with fertilizer at certain times in a plant's lifecycle. Farmers typically use aged manure as a nitrogen source, which may put their customers at slight risk of pathogens in their produce. Synthetic fertilizers are used by most non-organic farmers and gardeners, leaving a large carbon footprint and upsetting soil microbial communities. Compost adds some nutrients, but the nitrogen is typically consumed within six weeks.

Healthy soil has the ability to cycle nitrogen to plants from the activity of microbes with no outside supplementation. Healthy soil requires the presence of live plant roots throughout the year, e.g. cover crops, with no more than three weeks dead space. If one added compost…

Pretty, Hardy Weed

After considering problems in critical areas, the next logical runoff concern is that from slopes in general - the steeper the slope, the greater the concern. Slopes not only erode easily, but they also often carry water away too quickly for it to infiltrate the soil. A slope of sandy soil can wash out very quickly and sandy soils are the norm here in Calvert County.

Such was the case at my church where a pocket pond filled up with sand that eroded from its banks before vegetation could stabilize the slopes. The county inspectors finally caught up to us and put us on notice to fix it. The repair plan involves filling up woven bags with the sandy deposits and stacking them on the eroded banks. In short order, we need to also establish better vegetation cover to avoid future problems. Here might be a good place to show how biochar and compost can allow things to grow in difficult conditions.

Not many plants want to grow on sandy slopes, but cypress spurge is one that I found recommended…

Clueless Commissioners

Hugelkultur may not be in the Maryland Stormwater Design Manual, but it doesn't matter for the majority of properties. If a development activity doesn't disturb more than 5,000 square feet of land, the Manual isn't applicable. Most developed properties under private ownership are not going to build more large surfaces or structures, they just get landscaped, so we can do lots of things not discussed in the Manual that will contribute to cleaning up the watershed.

Some locations are still subject to local restrictions; critical areas, for instance. There are many homes in Southern Maryland located in critical areas, i.e. within 1,000 feet of a tidal waterbody. They are critical for the obvious reason that their proximity to the water makes them, by far, the major potential contributors to water pollution. Critical area buffers are therefore, the primary element of watershed protection that should be enforced everywhere.

Violators of critical area rules are sometimes fined w…