20, 2004: “There are lots of casinos up and down
the river,” observed Estevan Arrellanos of the Rio Grande
during his heirloom fruit tree workshop at the recent New Mexico
Organic Farming & Gardening Expo 2004.
“But I think the biggest gamblers are the farmers. We buy
seed, but we don’t know if it is going to rain!”
Rain or shine, it was a safe bet that love of farming and good
food would attract 500 people to Albuquerque, New Mexico, on Valentine’s
Day weekend for the sixteenth annual Expo. Attendees from the Land
of Enchantment and the surrounding region, especially Colorado,
Arizona, the Navajo Nation, and Texas, had twenty-two workshops
from which to choose.
From building soil to building markets to water conservation in
the desert, Expo 2004 had no shortage of learning opportunities.
Below we look closely at three: The Farm as Natural Habitat; Organic
Sustainable Greenhouse Design and Production; and Choosing Appropriate
Equipment for Vegetable Production Systems.
Organic sustainable greenhouse design and production
Greenhouse growers who made the Friday morning session enjoyed
a thorough presentation by Paul Cross of Charybda, a certified organic
nursery that produces tomatoes, basil, and a full line of bedding
plants in Arroyo Hondo, New Mexico. Cross frequently tailored his
advice for desert Southwest growers, who get more annual sunlight
than growers anywhere else in the continental U.S. With this in
mind, Cross quipped that Southwestern growers need to pay attention
to where their greenhouse experts come from.
“If you follow Eliot Coleman’s Four-Season Harvest
in New Mexico, you’re gonna end up with fried compost on the
For example, while most areas of the country use an east-west axis
for siting conventional greenhouses, Cross urges a north-south orientation
in New Mexico, where there is plenty of solar gain. A north-south
axis gives row crops even light on both sides, minimizes the problem
of fixed shadows, and minimizes the amount of frozen snow trapped
on the north side, where it blocks ambient light instead of melting
into water catchment systems.
Another siting objective is to orient one narrow end of the greenhouse
to catch the wind and pull it through to minimize stress on the
structure. Asked what to do about the axis orientation when prevailing
winds are from the west, Cross said stick with a north-south axis
and plant windbreak hedgerows to send wind up and over the greenhouse.
“The biggest mistake people in New Mexico make is wondering,
how am I going to heat this?” said Cross. “You should
be thinking, how am I going to cool this?”
To reduce heat in the summer, Cross says paint everything you can
white. Aluminum structures reflect only 60% of sunlight, which means
the remaining 40% becomes heat. White paint is 80% reflective. Southwestern
greenhouses also should be covered 50-70% with shade cloth—Cross
recommends Aluminet—from the time temperatures climb in May
until October or November.
Farmers trying to extend growing hours anywhere with supplemental
light can use Cross’s advice to turn lights on before dawn,
stretching hours in the morning instead of the evening. Turning
lights on at sundown does not work well because plants are already
going to sleep by then, and shutting lights off at night confuses
beneficial insects such as bees, who cannot find their way home
in sudden darkness.
Water conservation, another topic of particular concern in the
southwest, is a good practice for any sustainable farmer.
“You want your water slightly on the acidic side, about 6.8
pH, and there’s no better water than the rain running off
the roof. It’s rich in nitrogen and carbonic acid,”
For water catchment, Cross recommends using gutters on the greenhouse
and UV-stabilized pond liners on the ground next to the greenhouse
with small channels leading to cisterns. The pond liners serve double-duty
as weed blockers, eliminating pest habitats the recommended fifteen
to thirty feet from the greenhouse.
For water storage, Cross suggested tanks buried partially inside
the greenhouse—three feet below ground, two feet above ground.
Designed this way, the tanks serve the permaculture principle of
stacking by storing water (which ideally should be 65-80° F.
for watering), providing thermal gain in the winter, and offering
a level surface on which to work with seedling flats.
Growers who want to install a pond might find pond liners expensive,
so Cross gave instructions for a poor man’s pond: dig a hole,
line it with carpet remnants, cover that with builder’s plastic,
lay another remnant upside down, and cover with stone. Southwestern
growers just need to remember that ponds can evaporate thirty-three
inches annually, while New Mexico gets only twelve. And ponds need
to be fenced for safety.
While too much heat is a problem in southwest summers, heat supplementation
is necessary for winter germination and growing. If looking at a
manufactured heater, Cross said to de-rate the heater 4% for every
1,000 feet of altitude.
With natural gas prices projected to double in the next four years,
however, Cross suggested supplementing with alternative heat sources.
Barrels of water stacked one foot off the ground can provide thermal
mass, preferably on the north side of the greenhouse, and compost
piles inside are great heat sources. Cross also suggested using
a fan in an intake box to blow warm daytime air through perforated
drain pipe snaked beneath greenhouse soils.
After covering greenhouse design, Cross turned to production tips.
For nursery production, consumers have come to expect short, stocky
plants, which industry growers achieve with chemical growth regulators.
As an organic grower, Cross built a giant rolling pin made of a
center spindle with a plastic pipe around it. Holding the spindle
with a partner, Cross brushes the top of his plant canopies with
the pin, simulating the action of wind outside to reduce internodal
length on the plants.
For seeding, Cross preferred a manufactured plastic handheld seeder
until he lost it and fashioned a replacement out of clay. Unlike
the manufactured seeder, Cross’s has a lip that allows him
to pour seeds back into storage easily when seeding is done.
Finally, Cross shared his twenty-first century technology for monitoring
pests: yellow plastic plates, sprayed with cooking oil and suspended
six inches above the plant canopy, one for every 500 square feet
of growing space. Beneficial insects tend not to be attracted to
the yellow plates; some growers use light blue plates to monitor
thrips. Cross checks the plates one a week to see what he has, then
washes them in soap and water.
Choosing appropriate equipment for vegetable
“Choosing and using the right farm or garden tools can mean
the difference between a happy, healthy, prosperous growing season
and one full of stress and disappointment,” says organic grower
Michael Alexander. “Or worse yet, the difference between continuing
to farm or giving up.”
Alexander reprised his equipment workshop for vegetable and fruit
growers at Expo 2004. Attendees received a thorough handout covering
everything from tractor types to bat houses to equipment sources
and enjoyed a slideshow featuring Alexander’s equipment on
Inside the greenhouse, Alexander has a number of recommendations
for optimum production. For seeding, he uses the Seed E-Z vacuum
seeder, which uses a vacuum to hold seeds onto indentions in an
aluminum plate that is inverted for dropping the seeds into flats.
The vacuum seeder has cut Michael and wife Sharlene Grunerud’s
planting time “to a fraction of what it was.”
Their potting mix is 1/4 vermiculite, 1/4 sand, 1/4 of their finest
compost, and 1/4 Coco Grow, an environmentally friendly peat moss
substitute that reduces harmful dust and is easier to re-wet when
dry. For watering seedlings, Alexander has settled on the Red Head
water breaker, which “produces a very soft flow with high
volume for quick, safe watering.”
To reduce temperature in the greenhouse, Alexander recommends building
a “wet wall” on one end. Connected to a thermostat and
made of a tube that dribbles water down through stacks of six-inch
pads of corrugated cardboard, the wet wall acts like a giant evaporative
cooler when fans at the opposite end of the greenhouse pull the
moisture through the structure. Place greenhouse thermostatic controls
at the center near the plant canopy rather than on an outside wall,
as Alexander mistakenly did with his first greenhouse.
For organic growers of nursery plants who are not forcing flowers,
Alexander suggests compiling a photographic catalog so customers
can see what the flowers will look like.
Taking attendees out to the fields with his slideshow, Alexander
shared advice for irrigation, cultivation, and clearing. Southwestern
growers using flood irrigation should consider leveling their land
using laser technology, says Alexander. Leveling eliminates soaked
beds that prevent seedling emergence and dry beds that prevent germination.
“Now that we’ve laser leveled,” said Alexander,
“we sow squash down the center of a 36-inch bed, water in
the furrows, and the seeds germinate.”
Alexander’s handout warns, however, that leveling more than
an inch or two is hard on the soil, so be prepared to restore fertility
with green manures and amendments.
For cultivation, Alexander’s favorite tractor attachment
is the rotary cultivator, or Lilliston Rolling Cultivator. Rotary
spikes on the cultivator slice and twist through the soil to uproot
small weeds, cut larger ones, and break soil crust. The spikes are
followed by a sweep that cuts missed weeds and cleans furrows for
irrigation. Supplement with hand cultivation using a stirrup hoe.
When kept razor sharp, it glides lightly and quickly under the soil
surface to uproot small weed seedlings.
To save back labor when cleaning rocks from furrows, Alexander
bent the ends of a garden rake upwards, shaping the rake to fit
into the furrows without harming the beds.
Alexander finished his presentation with advice for wildlife enhancement.
Bat houses provide a habitat for controlling pests, especially coddling
moths in orchards. Bat Conservation International has great information
After noticing that birds disappear from his fields when he removes
the tomato stakes, Alexander installed permanent perches to encourage
insect control. According to Alexander’s handout, drilling
5/16-inch holes six inches into the ends of 2x4’s or 4x4’s
and hanging them around the farm provides habitat for Orchard Mason
bees. Finally, when using his rotary mower on the farm, Alexander
mows slowly and raises the blade as high as practical to minimize
harm to snakes, which are important for rodent control.
The farm as natural habitat
Keynote presenter Dr. Laura Jackson, editor (with mother Dana Jackson)
Farm as Natural Habitat: Reconnecting Food Systems with Ecosystems,
held two workshops structured around the theme of her book. (For
a review of her book, click
here.) An ecologist and Associate Professor of Biology at the
University of Northern Iowa, Dr. Jackson led attendees at both workshops
through an exercise for mapping natural habitats on their farms
and marketing those habitats to customers.
Jackson began by sharing her ecological perspective on the importance
of organic farming. First on her list was not the elimination of
chemical residues on food (which she said concerns her more as a
mother), but a broader issue: the management of ecosystem processes.
Examples included biological diversity, tight nutrient cycling,
efficient decomposition processes, intact food chains, natural animal
health, and water migration.
“Because you rely on ecosystems,” Jackson told the
farmers, “you preserve and protect them.”
Jackson also sees organic farming as important because ecologists
do not, or at least should not, look at things in isolation.
“While it seems like we are less attentive to landscape processes
as a modern industrial society,” said Jackson, “we’re
actually just as dependent on the water, soil, and climate for our
food as we always have been.”
For example, climate scientists did research in Florida in the
aftermath of severe freezes in 1997, which destroyed $300 billion
of vegetable and fruit crops. They calculated whether the freezes
would have been as bad if Florida’s wetlands had not been
drained, which eliminated thermal mass and heat trapping humidity.
The scientists found that with intact wetlands, many areas would
not have frozen at all, and some would have frozen for shorter periods
The third reason Dr. Jackson cares about organic agriculture is
survival of the earth’s organisms.
“I’m a human, I’ve got children, I care about
people,” said Dr. Jackson. “But, humans currently appropriate
one-half of the plant biomass produced on the terrestrial part of
the earth. The rate of species extinction is between 100 to 1000
times faster than it was in pre-colonial times, and U.S. agriculture
is a leading cause of plant and animal endangerment, second only
to urban expansion.”
To help organic farmers explore and articulate the way in which
organic farms preserve natural habitats, Dr. Jackson led workshop
attendees through a small-group exercise.
Using graph paper and colored pens, attendees began by mapping
the natural features on their farms, those features important to
birds, wildlife, wild plants, and people. Then they mapped farm
inflows and outflows, including water, soil builders, seeds, feeds,
insects, wildlife, pollen, nectar, petroleum, weeds, and knowledge.
Finally, the small groups were to explore how to communicate the
habitat benefits of organic farming to customers, perhaps convincing
them to pay a premium for food that serves ecological systems. (Unfortunately,
the workshop ran short of time for this exercise.)
“Here’s the thesis of the book my mother and I edited
together,” said Dr. Jackson. “For a large number of
environmentalists and consumers, farms are ecological sacrifice
areas where we have written off the possibility of nature. Farms
are just for production.”
“Farms aren’t natural,” interjected
“That’s the way a lot of people think,” urged
Jackson, “and I think there’s a lot of room in the middle
that’s good for society, that’s good for just general
quality of life, that’s maybe good for the way the farm works.”