Buried Treasure

Beneath that mound in the backyard garden lies some very creative destruction.

By Sharon Parker 

(Editor's note: This article first appeared in the spring 2010 issue of  MOQ. The backyard referred to here is the author's former residence.)

When we moved into a modest 1927 bungalow on Fifth Avenue some 20 years ago, we picked what appeared to be the best location for a garden, and were pleased to discover that the spot boasted a rich humus that nurtured a vigorous crop of vegetables, even before our first compost pile was ready to use. Occasionally, we would push a shovel into the ground and turn up a steak bone or other remnant of somebody’s long-ago supper.

So we weren’t too surprised when one of our old-timer neighbors told us that Mrs. Nelson, who lived in the house from the time it was built until about 1980, used to bury her garbage in the backyard. Apart from the occasional bone, the only evidence of this long-ago practice was the richness of the soil that invigorated our vegetable garden.

I remembered that old garden last fall, after reading about “deep composting” in Thomas Powell’s little newsletter, The Avant Gardener. Powell described the “new” practice of burying compostable materials rather than amassing them in piles, also known by the German term hugelkultur, which means “mound culture.” It seemed a lot like what Mrs. Nelson used to do, which led me to investigate further, and now I have a small mound in my backyard, awaiting spring and the next phase in my hugelkultur experiment.

* * * * *

What’s different, if not truly “new,” about hugelkultur, is that it offers a way to compost woody plant materials that you wouldn’t ordinarily bother with in your compost pile, because they take seemingly forever to break down — things like tree branches and shrub trimmings, sunflower stalks, squash vines, corncobs and the like. Even heavy logs will eventually decompose after being buried underground. In constructing a full-blown hugelkultur mound, enthusiasts will use a front-end loader to do exactly that, burying logs large enough to build a cabin with. But not bones or meat scraps — as our backyard excavations attest, bones remain intact for decades (and such animal remains may attract unsavory critters, as well as an astute representative of the City inspections office).

Modeled after the natural process of decomposition that takes place in the woods, hugelkultur has caught on with folks in the permaculture movement. Consider how a fallen tree trunk rots, becoming host to lichen, moss, mushrooms, and then more green growing things. Such mini ecosystems last for many years; they foster valuable mycorrhizal relationships between plants, soil and fungi to facilitate the exchange of nutrients, and promote healthy moisture levels.

With hugelkultur, you bury those tough-to-compost materials under mounds of softer compostables and soil. The chunkiness of the buried materials also creates air pockets, which, say hugelkultur advocates, are good for roots. You don’t have to wait for the buried matter to decompose, either; you can plant as soon as you’re done building it. In this way, hugelkultur is similar to no-till gardening, in which a raised-bed is established by first covering the sod with multiple layers of newspapers, then piling soil on top, then planting. By the time the roots reach to where the lawn was, the newspapers and grass are well on their way to becoming nitrogen-rich compost.

* * * * *

I decided to make a hugelkultur mound in my backyard last November, so that it would be ready for planting early in the spring. I dug into one of my existing raised beds, piling the soil off to the side, until I had a depression about eight inches deep, then looked around for woody materials to bury. I fished out the logs from the bottom of the firewood pile, which had sat too long on the ground and were beginning to rot (“Great! A head start!” I thought), added pieces of a dead branch we removed from the Norway maple tree but never got around to burning, the sunflower stalks that are almost as tough as tree trunks, the spindly sticks from pruning the spirea hedge, and the squash vines from atop the compost pile, which had become a fibrous mass of tangles. The pile was now an unwieldy mess of twiggy matter, so I stepped into the middle of it and stomped around a bit to break things up and pack it all down.

In went some leftover segments of two-by-fours I found in the garage, but not the scraps of cedar fencing we had scavenged from a friend (the larger pieces of fencing frame our raised beds), because rot-resistant wood like cedar is, well, resistant to rotting. I would have also omitted black walnut, if I had any, because it’s allelopathic — it prevents other plants from growing.

Some time ago, a Master Gardener warned me that wood chips will draw nitrogen from the soil at the beginning of their decomposition process, so I added some organic fertilizer and plenty of green matter in the form of weeds and whatever was lying on top of the compost pile, for good measure. That may not have been necessary. Toby Hemenway, author of Gaia’s Garden: A Guide to Home-Scale Permaculture (Chelsea Green, 2009), doesn’t think this is a problem. “I suspect that the wood decomposes so slowly that very little nitrogen is bound up by the microbes gnawing at the logs,” he writes.

The rest of the partially finished compost from one side of our two-bin system went onto the growing heap, and I topped it all off with the soil I had removed at the beginning. I stepped back and admired the mound, which stood about three feet high at the center.

It will take years for the woody stuff at the bottom of all that to decompose, but it should make an excellent bed for squash and other sprawling vegetables in the meantime. Several gardeners say that berries of various kinds thrive in the mounds, too. And hugelkultur practitioners claim that these beds heat up in the spring because of the energy generated by the subterranean decomposition taking place, offering gardeners a head start on the season. I don’t know if my mound is large enough to generate any heat — it’s about four feet by four feet — but I’ll be watching for that this spring: I’ve got a soil thermometer and I’m prepared to use it.

At any rate, I know my husband will be happy if I stop tossing the spirea trimmings and squash vines into the compost — he complains about them getting tangled in the pitchfork when he turns the pile. Now, instead, when I prune the shrubs this summer, I’ll look for a spot to start a second hugelkultur mound. Mrs. Nelson would surely approve.

Two-by-Fours, Snickers Bars, and Furnaces

After a morning of drawing up plans and calculating lengths of lumber, Craig and I went to Home Depot today to get the wood to build the compost bins. We don't really consider ourselves fully moved in to a place until we get the compost bins built and the garden established, so these outdoor projects have now moved to the top of our old-house to-do list.

We walked into Home Depot with our list of so many two-by-fours and one-by-sixes and nails and other hardware. We  decided on horizontal planks for the sides rather than chicken wire, which is getting kind of fancy for us. We also decided not to splurge on cedar, which would be a little too fancy—and, besides, we figured that in the five or more years it takes for the cheaper wood to begin rotting, we may want to modify the design anyway.

After passing the helpful woman who directed us to the lumber department, we were greeted by a cheerful fellow with a clipboard, who said, "May I interest you in a furnace and air conditioner today?" We declined, and as we made our way to the shelves of two-by-fours, Craig mused, "Furnace, air conditioner, Snickers bar—all things you might buy on impulse, right?"

Then I smelled popcorn and started looking around for the source. "I must have popcorn," I said. And there she was, a smiling matronly woman standing next to a popcorn machine. "We give away popcorn every Saturday," she said. "And ask people if they'd like to sign up for a free estimate for any of these things—a furnace or air conditioner, perhaps? Patio or sidewalk?" I thanked her for the  popcorn but declined to sign up for the estimates.

We found the materials we needed, with assistance from a few more helpful orange-aproned people, all of whom seemed quite happy to have a job—and who isn't these days?—and made our way to the checkout. There I spied the candy bars and placed a Snickers on top of the two-by-fours to complete our purchase.

Despite the nice young man who cut the wood for us so we wouldn't have any boards longer than six feet, we found that we still had to allow them to protrude out the back of our Honda Fit, and so fetched a length of twine (of course they had precut pieces of twine available for just such a purpose) to hold the hatchback door down. Under the circumstances, we agreed that it would not be a good idea to take our lumber-laden little car on the freeway, which meant that we had to take the long way home.

"That's OK," I said. "We have a Snickers bar."

—SP

Urban phenology: all aflutter

One spring in early April I was out riding my bike when I spotted a large, dark butterfly fluttering over a mound of dirty snow. I did a double-take, for there was still a chill in the air and plenty of snow on the ground. In fact, this butterfly was perched on the snow, and appeared to be sipping from it, as though the pile of snow were a flower.

I later learned that the mourning cloak butterfly (Nymphalis antiopa—pictured here in my garden last summer), which overwinters as an adult, is known to emerge once temperatures are in the 50s, so keep a look out for them when you are out and about on these warming days. The one I spotted on the mound of snow was likely getting moisture from it.

Other flyers (birds, that is) we don't see much are here or soon will be, too, some just passing through to nesting grounds farther north, and others returning to the Twin Cities as the melting snow and ice exposes food and open water. I know I'm not the only one who's heard the honking of geese overhead at night (many migrating birds fly at night), or spotted robins in the tree branches.

According to the Freshwater Society's Weatherguide Calendar, we should be spotting various waterfowl this week as the lakes continue to open up, and red-wing blackbirds may be heard trilling any day now.

Over at Twin Cities Naturalist (which posts a phenology update every Monday), naturalist Kirt Mona photographed a northern harrier recently returned to the area. And the Minnesota Birdnerd blog offers a migration map, updated periodically, so you can keep tabs on the movement of birds heading our way, as well as reports of recent birding opportunities for the avian fan.

It helps to have these cheerful migrants to draw our attention away from the muck and litter that the receding snowbanks are exposing, doesn't it?

A botanical path from St. Patrick to the Easter Bunny

Have you ever questioned whether the “shamrock” plants sold at grocery stores and florists this time of year are really shamrocks? The word shamrock is not a botanical name, but a common one derived from the Irish seamrog, a diminutive form of seamar, which means trefoil, clover, or even honeysuckle. (Webster's )

The “shamrock” plants you see in stores are oxalis, a plant of either South American or Mediterranean origin. Oxalis, also called wood sorrel, are probably called shamrocks because of the way they resemble clover.* And perhaps they make a more attractive potted plant than the weed that is more likely the true shamrock, as common in Ireland as it is in our lawns.

In 1893, Irish naturalist Nathaniel Colgan set out to determine which plant is the “true shamrock”; or, as he put it,“to take in hand the inquiry into the species of our national badge.” He asked both subscribers to the journal Irish Naturalist and the Catholic priests in all the Irish-speaking districts of the country to send him specimens of the plant they considered to be the true Irish shamrock. The winner of this contest was Trifolium repens, or the plant we know as Dutch white clover.

Being a fan of this common lawn weed, I was rather pleased to learn that. And it led me to want to grow some clover indoors. The first year I tried it I thought it would make a charming filler for our Easter baskets, but I discovered that it takes much longer to grow clover to an attractive leafy stage than it does to grow grass, so I missed the mark. This year, with Easter arriving so late (perhaps you'd like our handy Useful Calendar to help you keep track of such things), there’s just enough time to fill your basket with clover if you plant it this week.

If you want to try it yourself, here’s what you do:

• Get clover seed where you would buy lawn grass seed, at garden centers and hardware stores. It’s not always easy to find this early, so you might check one of the larger garden centers if your neighborhood one doesn’t have it yet.

• Scatter it thinly on the surface of some soilless seed-starting mix that you thoroughly moistened already, cover loosely with plastic to keep the moisture and warmth in, and place the pot or basket in a sunny window or under artificial lights. A little heat from underneath may help speed germination, so if you have radiators, set it on them until the seedlings emerge. Of course if you’re starting the seeds directly in a basket, you’ll want to line it with plastic first. And, as this will not have drainage, you’ll need to be careful not to overwater it.

• If droplets of water collect on the plastic covering, loosen it or remove it for an hour or so to let some of the water evaporate. Too much wetness will encourage mold to grow and may rot the seeds before they can germinate. But you don’t want it to dry out too much either, so it’s kind of a balancing act at this stage. Mostly you want to keep the seeds covered and the soil moist until the true leaves come, which will be the second set of leaves to open. Once those are out, you can let the soil surface dry a bit between waterings.

One of the difficulties I have had was that I scattered too many seeds on the soil surface and found that they were much too crowded as they sprouted. Too avoid this, mix some seeds with an equal amount of the soilless mix before spreading them on the surface. Don’t bury the seeds, though, they need light to germinate.

And that’s about it. One of the advantages of growing clover rather than grass is that it’s less appealing to cats, but the Easter Bunny is sure to appreciate it. When Easter is over, toss the clover in your compost or just in the garden somewhere. Clover is a legume and will add a little nitrogen to the soil.

—SP

*Although I linked this sentence about oxalis to the Wikipedia entry on the topic, I did find several wonkish botanical sites confirming that the various species of the oxalis genus are either South American or Mediterranean. Wikipedia is a handy resource, but it’s always a good idea to check up on anything you find there.

Skittering over the lake

Earlier this winter, the park board delayed opening the skating rinks because the insulating cover provided by our early and abundant snowfall delayed the freezing of the lakes. But now it appears that the prolonged cold weather has triggered another delay of sorts: the park board recently announced that instead of closing after Presidents’ Day, as has been the custom most winters, the city’s ice rinks will remain open until March 6. We can thank our cold weather for that extended opportunity.

I may have to get myself another pair of ice skates. When we moved house about five years ago it was under some duress, and so it was a few months afterwards that I discovered that I must have left my ice skates behind. I’ve never been all that avid an ice skater, so I haven’t gotten around to replacing them yet, but the idea of ice skating continues to appeal to me, and I do have especially pleasant memories of one particularly cold winter that was notable for its lack of snow, when the kids and I skated to the middle of Lake Harriet.

The kids were elementary-school-age, and we were new to homeschooling that winter, so the novelty of having our days our own gave us the exhilarating sense that we were getting away with something. Like we were skipping school, except this was school — the museums, the libraries, the parks, the lakes, everywhere. It was cold and snowless, a combination that had the lakes frozen firm and sure by early December. We had come to know another homeschooling family who were ardent fans of winter, and they pulled and tugged and persuaded us to meet them at the lake to go skating on a bone-chilling day.

I know that it was unusually early for skating because I remember a man jogging around the lake commenting just loudly enough for two irresponsible mothers to hear how crazy we were to attempt the ice. But the warming house was open, and the park board staff assured us that they had checked the depth of the ice with an auger, so we skittered out onto the vast surface unafraid.

Because there was no snow, we could skate the whole lake. It reinforced our feeling that the entire world was ours for the exploring. We looped around the ice fishermen, inquiring cheerfully about their luck, and watched the sail of an ice boat snap to attention as it caught a frigid blast and sent the little vessel skimming across the sleek surface.

The lesson we learned from our homeschooling friends that year, if I may be so didactic, was that the joyful embrace of winter mitigates any discomforts the season throws our way. It’s not that I’ve become an enthusiast for our coldest months, I still prefer the easy comforts and lighter clothing of the other three seasons, but the memory of that pristine moment when the snowless cold created a playground just for us tugs at me now, the way our friends did on that December day.
—SP

It's Catalog Season

Even though the first garden catalogs started arriving in early December, garden catalog season's true beginning is now—that is, on or after twelfth night, the fifth of January. How do I know this? Well, I just made it up, of course. But doesn't it make sense to you? Around the time you put away the holiday stuff and haul the tree out to the backyard to drop its needles into the compost bin, a gardener's thoughts naturally turn to garden planning. Ergo: catalog season.

Years ago, after reading Katharine White's famous essay "Onward and Upward in the Garden," in which she reviewed various garden catalogs with the same attention she would give to fine literature, I made a point of requesting all the catalogs she endorsed in the essay. But her favorites came from East Coast and Southern nurseries, and I found myself frequently discouraged by the number of attractive perennials they offered that weren't hardy in Minnesota's climate—including some that are grown here, but either the catalog compilers in more temperate climes didn't realize it, or the specific lines they offered had not proved their mettle by enduring what we would call true winter.

I also found myself increasingly turned off by White Flower Farm's pretentious Amos Pettingill (although the story behind this pen name is interesting enough), as well as its decidedly anti-urban bias, with its insistence that full sun could only mean sunshine literally all day, from morning to dusk, with no acknowledgment that plants requiring full sun were thriving in city gardens everywhere with as little as six hours of sunlight daily.

 I have since dropped all those catalogs, as well as the ones I used to get because they were Dad's favorites (he loved Burpee's tomatoes most of all) but which began to not suit me so much, and have gradually replaced them with catalogs that are more fitted to our character-building climate as well as my Midwestern rustic-urban (is that an oxymoron?) sensibilities, and my peculiarities of taste. Some of these I found through their ads in the Minnesota State Horticultural Society's magazine, now called Northern Gardener, and some I discovered at a winter gathering of gardeners in which participants brought their favorite catalogs for a kind of show-and-tell (along with coffee and treats, as I recall).

I expect more catalogs to come trickling in over the next few weeks, and in the meantime I'll get started on perusing the ones I've received so far, flagging pages with sticky notes, making lists and sketches, and then winnowing it all down to something approaching a realistic ambition for my not-so-big and just-sunny-enough city plot this summer. I'll even review a few of them on this blog in the coming weeks, even though reviewing garden catalogs has become something of a cliche since Katharine White started it all some 60 years ago. So I'll make no pretense of originality, but admit that reading garden catalogs is a cozy winter pastime enjoyed by gardeners everywhere.

Here are links to the catalogs pictured, in case you are eager to get some of them for yourself:
Jung Seeds, John Scheepers Kitchen Garden Seeds, and Nichols Garden Nursery.

How David Douglas Brought a Popular Christmas Tree into Cultivation

Lewis and Clark called it Tree No. 5 when they made their famous trek through the American northwest 200 years ago. There is no indication that they had any thought of decorating what we now call Douglas-fir, and they most certainly didn’t cut one down and drag it home for Christmas, but no doubt they admired its graceful towering beauty—the species native to the Pacific Northwest reaches 200 feet and more at maturity, and lives hundreds of years. (The photo was taken by Bob Dunlap for Gustavus Adolphus college, and is used here with the photographer's gracious permission.)

About 15 years earlier, Scottish physician and naturalist Archibald Menzies was journeying with Captain George Vancouver on the good ship Discovery, and made a brief note about this same tree, which he spotted on the island that would later be named for his captain.

But it was the intrepid plant hunter and Scotsman David Douglas who, in 1827, brought seeds back to England, where it has since become as popular a Christmas tree as it is here, mostly due to its habit of holding onto its needles much longer than spruces or pines, a quality it shares with other firs, such as balsam and Fraser.

Except Douglas-fir isn’t really a fir at all, which is why botanists prefer to hyphenate the name, nor is it pine or spruce. Because it has such distinctive cones, which are the seed vessels and therefore the feature of the plant used to classify it, a whole new genus was coined—Pseudotsuga, meaning “false hemlock” (why not Pseudoabies for “false fir” I can’t tell you). And because botanical etiquette calls for choosing the second name, which narrows it down to species, after the first person to discover it (“discover” here meaning to “write something about it in a European language”), the proper scientific name of the plant is now Pseudotsuga menziesii.

What I really like about Douglas-fir, besides its obvious charms, is its namesake—the unofficial one, that is, a kind of Indiana Jones of botanists, who went to great lengths to find and bring home hundreds of specimens of plants to England at the behest of the Royal Horticultural Society. He kept detailed journals of the plants he encountered, as well as his adventures along the way, which the Horticultural Society published in 1914.

During a plant-collecting expedition in 1826, Douglas went in search of a huge pine tree hitherto unknown to his peers back home, which he had learned about from talking to various Indians, as well as the French settlers who were already pretty well-established thereabouts. Now known as the sugar pine, or Pinus lambertiana, it’s one of the tallest of this genus—like the Douglas-fir, it’s known to reach about 200 feet. The story of how Douglas managed to gather cones of that tree is a colorful one and worth sharing. He not only endured some of the Northwest’s famously miserable weather, but also language barriers and, ultimately, a misunderstanding that required some quick thinking on his part.

Douglas spoke French, knew a smattering of the Indian languages of the area, and always carried a pouch of tobacco, the currency of diplomacy at the time, all of which helped him gather information about the plants he sought. “[T]wo individuals … both talk the Chenook tongue fluently, in which I make myself well understood; from the questions I have put to them and the answers given, I am almost certain of finding [the sugar pine] in abundance,” he wrote in his journal.

But for the journey to find these and other specimens, he had to hire a guide with whom he could communicate only in a form of sign language. And it rained nearly the entire two months of the journey. “The rain of the two days before rendered the footing for the poor horses very bad; several fell and rolled on the hills and were arrested by trees, stumps, and brushwood,” he wrote on October 16, 1826.

About a week later, he wrote, “Last night was one of the most dreadful I ever witnessed. The rain, driven by the violence of the wind, rendered it impossible for me to keep any fire, and to add misery to my affliction, my tent was blown down at midnight, when I lay among bracken rolled in my wet blanket and tent till morning. Sleep of course was not to be had, every ten or fifteen minutes immense trees falling producing a crash as if the earth was cleaving asunder . . .”

The pack horses didn’t like it much, either. “My poor horses were unable to endure the violence of the storm without craving of me protection, which they did by hanging their heads over me and neighing.” But the intrepid collector had his priorities clear—“I am glad I took the precaution of carrying the specimens of seeds and plants on my back, otherwise they would have been much destroyed.”

When he finally reached a stand of the sought-after pine, he measured “the largest one I could find that was blown down by the wind,” which he found to be  57 feet 9 inches around the trunk, and 215 feet tall.

But the coveted cones, containing the seeds that he wanted to take back with him, were at the tops of the very largest trees. He managed to collect only three cones—by shooting them down, which alarmed the local Indians and got Douglas and his guide into a bit of fix. “I took my gun and was busy clipping [the cones] … from the branches … when eight Indians came at the report of my gun. They were all painted with red earth, armed with bows, arrows, spears of bone, and flint knives, and seemed to me anything but friendly.”

The language barrier impeded Douglas’s attempt to explain what he was doing, and the eight declined to set aside their weapons (he doesn’t mention whether he set down his), so Douglas offered them tobacco to climb some of the trees to fetch more cones, while he and his guide beat a hasty retreat.

So it was that the sugar pine was introduced into cultivation. Somewhere in the midst of that particular quest, he also picked up some cones of the Douglas-fir, much to the delight of holiday revelers ever since.

—SP