Planning for sustainable farming by feeding the soil. Growing and maintaining healthy soils. Using crop rotations, cover crops, compost and organic mulches. A step-by-step guide to crop rotation. Example of a ten part rotation of vegetables and cover crops. Benefits of crop rotations, cover crops and compost. Opportunities to grow cover crops. Fitting the cover crop with the goal; smothering weeds, fixing nitrogen, scavenging leftover nutrients, improving soil drainage, grazing for small animals, bio-fumigation, killing nematodes. How to make aerobic (hot) compost. Resource list included.
2. What’s in This Presentation
Planning for sustainable farming – feed the soil
Growing and maintaining healthy soils
Crop rotations
Cover crops
Compost making (& growing)
Organic Mulches
Resources
3. Grow Healthy Soil
Healthy soil grows
healthy plants
Feed your soil, not
your plants
Tatsoi. Credit Wren Vile.
4. What are Healthy Soils?
• Healthy soils produce good crop yields, without
degrading the environment.
• They promote plant, animal, and human health.
• Healthy soils produce sturdy crops that resist
pests and diseases.
• But don’t blame the victim! Diseases need three
things for the disease to take hold: a susceptible
host, a disease organism and suitable conditions.
• Grow strong plants and make the conditions
unsuitable for diseases and pests. Sometimes
plagues still strike!
5. Healthy Soil is Alive
One acre of organic soil can have 2400 pounds of fungi and 1500 pounds
of bacteria. These contribute to good soil structure, breakdown
nutrients, and increase levels of organic matter. USDA image
6. Signs of a Healthy Soil
• Has good crumb structure, lets air and water in
and out.
• Resists erosion and compaction.
• Absorbs, holds and releases nutrients.
• Promotes good root growth.
• Provides good habitat for soil organisms.
• Has a moderate pH (6.0 – 7.0).
• Has low levels of salts and toxins.
• Has balanced fertility with adequate levels of
nutrients.
7. Crop Rotations Bring Many Benefits
Maximize productivity,
Optimize the health and fertility of the land,
Reduce pests and diseases,
Increase opportunities to plant cover crops,
Meet Organic Certification requirements,
Make the planning work easier on the brain.
8. Before Planning a Rotation
Decide how your farming will support you
Decide what you want to grow
Figure out how much of what you need
Have an idea of when to plant each crop.
Planning is definitely circular, but you need to
start somewhere!
9. Steps to Creating a
Permanent Rotation
a. Figure out how much area is needed for each
major crop (the ones needing the largest
amount of space).
b. Measure and map the land available
c. Divide into equal plots
d. Group compatible crops together to fill each plot
e. Determine a good sequence
f. Include cover crops
g. Include no-till crops
h. Try it for one year, then make improvements
10. Space Needed for Major Crops
• Sweet corn: 6 or 7 plantings of about 3,500 ft2 (322 m2) each
• Spring planted potatoes: about 7,000–9,000 ft2 (644–828 m2)
• Summer planted potatoes: about 7,000–9,000 ft2 (644–828 m2)
• Spring broccoli & cabbage: 4,000 ft2 (368 m2)
• Fall broccoli & cabbage: 7,000 ft2 (644 m2)
• Winter squash: about 8,200 ft2 (736 m2)
• Watermelon: about 9,000 ft2 (828 m2)
• Sweet potatoes: about 4,300 ft2 (396 m2)
• Tomatoes: 4,000 ft2 (368 m2)
• Peppers: 2,200 ft2 (202 m2)
• Garlic: about 3,600–4,000 ft2 (332–368 m2)
• Fall carrots: about 3,600–4,000 ft2 (332–368 m2)
11. Divide the Land into Equal Plots
In our gardens, the 7,000–9,000 ft2 (644–828
m2) crops (spring planted potatoes, summer
planted potatoes, fall broccoli &
cabbage, winter squash, watermelon) will
naturally each fill one plot in our rotation,
so that was a good size to aim for in setting
plot size.
This size produced 10 plots, suggesting a ten
part rotation
12. Group Other Crops Together to Use
About the Same Area:
Two or three corn
plantings together in one
plot
(3,500 ft2 (322 m2) each)
Spring broccoli together
with overwintered garlic
(4,000 ft2 (368 m2) +
3,600–4,000 ft2 (332–368 m2 ))
Tomatoes together with
peppers
4,000 ft2 (368 m2) +
2,200 ft2 (202 m2)
Left to right: Broccoli under
rowcover, garlic, strawberries.
Photo Kathryn Simmons
13.
14. Walk Around our Rotation
Year 1. Winter Squash followed by
Rye and Austrian Winter Peas
• 8,200 ft2 of winter squash will
satisfy our needs. That fills one plot.
• Winter squash are sown in late
May, so there is time for a legume
winter cover crop to reach flowering
before we need to prep the soil for
the squash.
• We have one other main crop also in
the cucurbit family: watermelon, so
we plan to keep that distant time-
wise in the rotation
• Winter squash finishes on our farm
on Halloween, early enough to
include crimson clover or Austrian
Winter Peas in the following cover
crop mix
15. Year 2. Late Sweet Corn
and Sweet Potatoes
• Our late (6th) corn sowing and our
sweet potatoes are both planted
late in the season. Having them
share a plot works in terms of
allowing the preceding crimson
clover or Austrian winter pea
cover crop time to flower.
• Late corn can be under-sown with
oats and soy to provide a winter
cover crop that is easily
incorporated before the potato
planting next March.
• The sweet potatoes finish in
October, too late to sow oats
before next year’s spring
potatoes. So we follow the sweet
potatoes with wheat.
Sweet potatoes and late corn.
Photo Bridget Aleshire
16. Year 3. Spring Potatoes Followed by
Fall Brassicas
• Potatoes are said to do well after
corn, so we put our spring
potatoes after the previous
year’s late corn, and our summer
potatoes after the previous
year’s middle corn planting.
• We harvest the potatoes in early
July, till in compost and
immediately transplant our fall
broccoli and cabbage.
• We undersow the fall brassicas
with a mix of clovers (white, red
and crimson) about a month
after transplanting. This becomes
Year 4’s All Year Green Fallow.
Potatoes emerging in spring. Photo Kathryn Simmons
17. Year 4. All Year Green Fallow
The clover sown under the fall
brassicas grows all next year, if all
goes well.
We have contingency plans:
In spring, once the warm weather has
arrived, if the weeds are too bad, or
the clover stand not thick enough, we
turn the clover under and sow
sorghum-sudangrass hybrid with soy.
This gets mowed to a foot (30 cm)
when the sorghum-sudan is four feet
(1.2 m) tall, to encourage deeper
rooting for better soil drainage, and
can stay until killed by the frost.
If the plot is looking good, we let the
clover grow all summer, mowing to
prevent the clover seeding.
In August, we review again: if we still
have the clover we may turn it under
and sow oats. Or we may leave it over
winter.
Fall broccoli under-sown with clovers
18. Year 5. Early Sweet Corn,
Half Followed by Garlic
• We get two food crops
in year 3 and none in
year 4. The Green
Fallow is ready for
disking early in year 5 to
plant our first sweet
corn.
• The early corn can be
followed by fall garlic.
Sweet corn under-sown with soybeans.
Photo Kathryn Simmons
19. Year 5-6. Sweet Corn → Oats
→Garlic →Buckwheat →Carrots
A tight rotation:
After early corn in year 5, we
sow oats and divide the plot.
We keep half for spring
broccoli in year 6.
We mow the other half from
time to time until late fall
(year 5), then disk and plant
garlic.
We harvest the garlic in June
of year 6, sow buckwheat and
soy,
Then sow fall carrots in late
July or early August.
That half-plot grows 3 food
crops in 2 years.
Garlic harvest, Photo Rayne Squier
20. Year 6. Spring Brassicas in the Other
Half.
Spring broccoli and cabbage can be
followed by rye, hairy vetch and Austrian
winter peas sown in early September, in
good time to grow a thick stand for no-till
tomatoes in year 7.
Photos Kathryn Simmons
21. Year 7. Paste Tomatoes and Peppers
• We mow the cover crop close
to the ground, let it wilt for a
day, then transplant paste
tomatoes and peppers into
the dead mulch in early May.
• The mulch does break down
after about six weeks, so then
we roll out bales of spoiled
hay between the rows.
• This crop doesn’t finish till the
frost, and we have all the
posts to remove before we can
sow a cover crop, so it is
usually rye with Austrian
winter peas.
22. Year 8. Watermelon
• Watermelons are not
planted till mid-May, so the
Austrian winter peas have
time to flower before we
disk the cover crop under in
preparation for planting.
• We have finished with
watermelon harvesting by
late September, so we disk
the plot and sow rye with
crimson clover for the winter
cover crop.
Crimson Sweet watermelon and morning glory. Photo
Kathryn Simmons
23. Year 9. Mid-season Sweet Corn
Mid-season corn is finished in time to establish rye and
crimson clover, which will do well and produce lots of
nitrogen and biomass before we need to plant the June
potatoes in year 10.
Three varieties of sweet corn sown on the same day, to extend the harvest. Photo Kathryn Simmons
24. Year 10. Summer Potatoes
• Our second round of potatoes
are planted in mid-June, giving
the crimson clover plenty of
time to flower before we need
to disk and plant.
• To combat the heat of
summer, we hill and mulch the
potatoes immediately after
planting.
• They are ready to harvest in
October, and we follow with rye
and crimson clover or Austrian
winter peas.
June-planted potatoes. Photo Kathryn Simmons
25. Benefits of planned crop rotations
This tight crop planning might sound mind-boggling, but for us
it’s very worthwhile.
The division of the gardens into 10 plots gives us mental and
psychological advantages - we don’t have to think about the
whole of the area all of the time.
In spring we “open up the rooms” one or two at a time to
plant. By the beginning of July everywhere is in use.
In August we start to put the plots “to bed” with their winter
cover crops.
Annual expansion and contraction of the space needing our
attention helps us to stay sane and focused and keep
perspective.
This system helps us get high productivity from our
land, while taking good care of it.
26. Cover Crops - Oats
For early spring food
crops, a preceding cover
crop of oats (maybe with
soybeans) is ideal, as it
winter-kills and is easy to
incorporate.
Oats need to be sown at
our farm in August or early
September (by 9/17), so
they need to follow an
early finishing crop, such
as spring brassicas, spring
potatoes or early corn.
Photo Oklahoma Farm Report
27. No-till Cover
Crops We plant our tomatoes and
peppers into a mowed cover crop
of winter rye, hairy vetch and
Austrian winter peas. Austrian
winter peas are said to reduce the
incidence of Septoria leaf spot in
following tomato crops, so we
now include them in our no-till
planting.
This reduces inversions of the
soil, and the vetch (if plentiful) can
supply all the nitrogen the
tomatoes need.
Rye and vetch is best sown here in
early to mid-September, creating
another restriction on which crops
the tomatoes could follow.
Winter rye and hairy vetch. Photo
Kathryn Simmons
28. Leguminous Cover Crops
o To get best value from crimson
clover, we need to wait until it flowers
— mid-April at the very earliest —
before turning it under.
o So after crimson clover it’s best if the
next food crop goes in after the end of
April, such as later corn
plantings, winter squash, transplanted
watermelon, tomatoes, sweet
potatoes or June-planted potatoes.
o Another factor is that crimson clover is
best sown here before October 14, so
it has to follow a crop that is finished
by then.
Crimson clover flower, Photo Kathryn Simmons
29. Late Fall Cover Crops
• Austrian Winter Peas can be sown as late as
11/8 here, so we add them to our later rye
and wheat cover crop sowings.
• Photo FifthSeasonGardening.com
• Winter wheat is easier to
incorporate into the soil
in spring, but winter rye
can be planted later than
any other cover crop.
30. Popping in Summer Cover Crops
If we have a four week
gap between crops in
warm weather, we
sow buckwheat.
If we have 6 weeks, we
sow soy with
buckwheat.
Japanese Millet
Sorghum-sudangrass
Shown here after mowing.
Photo Kathryn Simmons
31. Cover Crop Opportunities
Undersowing at last cultivation
(oats and soybeans in corn shown
here.)
After vegetable crops, in summer
or fall
In spring, between an early
vegetable crop and a later one
After long season crops, for
winter
Late winter or early spring, if the
area will not be planted with
vegetable crop until late spring.
We use oats.
Frost-seeding of small seeds such
as clover: Broadcast in the early
morning, when ground is frozen.
As it thaws, the water draws the
seeds down into the soil. Works
well for clovers.
To replace a crop failure.
Photo Kathryn Simmons
32. Fitting the Cover Crop With the Goal
• Smothering weeds: sorghum-sudan, cereal
rye, buckwheat, brassicas (we don’t do brassica cover crops –
rotation, bugs).
• Fixing nitrogen: clovers, vetches, Austrian winter
peas, cowpeas, soybeans, lentils, sunn-hemp.
• Scavenging leftover nutrients : small grains, brassicas, annual
ryegrass (we don’t use annual ryegrass either – danger of it
becoming a weed)
• Improving soil drainage: sorghum-
sudangrass, sunflower, daikon, sweetclover, alfalfa, brassicas,
sugar-beet or forage-beet (never tried that.)
• Grazing: brassicas, clovers, small grains, annual ryegrass.
• Bio-fumigation: brassicas, sorghum-sudan, sunn-
hemp, sesame.
• Killing nematodes: Pacific Gold mustard, white lupins, Iron
and Clay cowpeas, OP French marigolds, sesame.
33. Incorporating Cover Crops into the Soil
• If possible, grow to early bloom for max biomass
• Incorporate before plants set seed
• Mow with a rotary mower (eg bush hog) which
chops the plants into small pieces. (Sickle-bar
mowers and scythes leave long strawy plants)
• Till shallowly, put cover crop where soil life is
most active, not deeper.
• If direct-sowing the next crop, incorporate cover
crop 3-4 weeks before sowing date, especially
winter rye.
34. Compost Making
• Many farms make their own compost -this
improves the soil, uses materials that could
otherwise be a waste disposal problem.
• USDA Organic Certified Farms need to follow
Organic rules.
35. Compost is Central to our Soil
Fertility Program.
• One of our community businesses is making and selling
tofu. Okara is a high-nitrogen waste product from tofu
making, the part of the soybeans that doesn’t go into the
soymilk.
• We mix in high-carbon sources such as sawdust (waste
from our hammock-making business) or woodchips that we
trade for with a neighbor.
• We also add kitchen scraps from our dining hall,
• and sometimes weeds or crop refuse from our garden. In
the summer we don’t collect up the weeds, just let them
die in place, as that is easier.
• We don’t have specialized compost-turning machines or
screens. We use the tractor bucket to lift and turn the piles.
36. Compost Making is Both Art and
Science
• There are several methods and recipes.
• Most people strive to make hot (aerobic)
compost, by combining 1 to 3 parts high-carbon
materials with 1 part high-nitrogen materials in a
25:1 to 40:1 C:N ratio, with enough water to
make the piles damp and enough air to keep the
bacteria alive.
• The initial mesophilic stage lasts for the first two
to three days after the pile is made. Bacteria
which are active at 90°F–110°F (32°C– 43°C)
begin to break down the sugars, fats, starches
and proteins.
37. Hot (aerobic) compost
• The pile heats up and
moves into the thermophilic
stage, which lasts several
weeks. Temperatures in the
middle of the pile can reach
120°F–150°F (48°C–66°C).
• Thermophilic bacteria
increase, and keep working
as long as decomposable
materials remain available
and the oxygen supply is
adequate.
• Pathogens, weed seeds and
fly larvae are destroyed, and
the particle size of the
compost becomes smaller.
Large-scale compost-turning equipment
38. When the pile starts to cool, turn it
• A decrease in temperature shows that more oxygen or more water is
needed.
• The pile benefits from turning during this stage to provide more oxygen
and remix the material, so that all of it can be composted.
• Turning also prevents the pile from overheating — above 150°F (66°C), the
thermophilic bacteria can be killed.
• During turning, more water can be added if needed to keep the pile damp
but not dripping.
Large scale
compost-turning
machinery
39. Compost Trouble-Shooting
Too much water will cause air to be excluded, and
the pile will slow down, go anaerobic, and emit
foul-smelling by-products.
High-nitrogen mixes are likely to lose (waste)
nitrogen by volatilization as ammonia.
Some loss is inevitable, but compost-makers
strive to minimize loss by getting a good balanced
mix.
If there is not enough nitrogen in the mix, the pile
will not heat up and the process will move slowly.
40. When the Compost Stops Heating
After the compost materials have all been consumed by the bacteria and the
nitrogen mineralized (converted to nitrates which will be available as plant
nutrients), the pile cools to around 100°F (37.7°C).
It can no longer be reheated by more turning, and it is left to cure for about
thirty days. This allows beneficial microorganisms to recolonize the compost.
The carbon in mature compost is resistant to further breakdown, and the
nitrogen, initially contained in the bodies of microbial soil life forms, slowly
becomes available to the plants.
It is then ready to be used, or if you like, screened first.
Large-scale compost
screening equipment
41. Finished Compost
Finished compost ideally has a C:N
(carbon:nitrogen) ratio of 10:1.
If the C:N ratio is greater than about
25:1, almost no nitrogen is available from the
compost and it is unable to mineralize.
Between 16 and 20:1, about 10 percent of the
N is available.
Even at a C:N ratio of 10:1, only half of the
nitrogen is available in the near term.
42. Compost is a Long-Term Plan!
Because it breaks down slowly, generally about 10
percent of the nitrogen will remain after harvest for
the next crop (assuming an adequate amount of good
finished compost was used).
Some growers aim to build the soil to a high overall
fertility level, and then maintain that level with smaller
applications of compost each season.
Others aim to apply a consistent amount each year.
Whatever your aim, it is generally agreed that the
occasional shortfall in compost application will not be
too dire if the soil fertility is high from previous
applications.
43. How Much?
Compost enhances the soil organic matter and humus, and
improves soil structure.
Its effects last longer in the soil than cover crops and crop
residues, especially in humid conditions where the
breakdown of plant material is very rapid.
In addition, compost can add a range of beneficial bacteria
and fungi to the soil, which can inoculate plants against
diseases by inducing systemic acquired resistance in them.
The plants produce antibodies and other protective
compounds before any infection occurs.
In his Winter Harvest Handbook, Eliot Coleman
recommends spreading compost at 5 gallons/ 25 ft2 or 15
tons/acre (8.6 l/m2) of raised beds, for each successive
crop.
44. Growing Compost Materials
• If you have land where you are not growing
food crops and don’t want to improve the soil
by growing cover crops, you can grow
compost crops, to cut and haul to your
compost piles.
• This can be a good way to grow food crops
very intensively in a small area, with the
compost crops growing elsewhere.
45. Organic Mulches
• Organic mulches such as
straw, hay, sawdust, woodch
ips, tree leaves, newspaper
and cardboard all add
organic matter to the soil.
• Here we are preparing a
new strawberry bed
mulched with two layers of
newspaper and dried
sorghum-sudangrass cut
from the plot in the
background.
Photo Luke J Stovall
46. Resources - General
ATTRA attra.ncat.org
SARE sare.org -A searchable database of research findings
SARE Crop Rotations on Organic Farms, A Planning Manual, Charles
Mohler and Sue Ellen Johnson, editors.
extension.org/organic_production The organic agriculture community
with eXtension. Publications, webinars, videos, trainings and support.
An expanding, accessible source of reliable information.
Growing Small Farms: growingsmallfarms.ces.ncsu.edu click Farmer
Resources. Debbie Roos keeps this site up to the minute.
Jean-Paul Courtens , Roxbury Farm www.roxburyfarm.com. Under
the Information for Farmers tab you’ll find great stuff.
The Center for Environmental Farming Systems at North Carolina
State University has good information on compost-making, such as
Composting on Organic Farms.
Compost recipe software is available from Cornell University
www.cfe.cornell.edu/compost/science.html
47. Resources - slideshows
Many of my presentations are available at www.Slideshare.net . Search for Pam Dawling. You’ll find
Crop Rotations
Cold-hardy Winter Vegetables
Fall Vegetable Production
Intensive Vegetable Production on a Small Scale
Succession Planting for Continuous Vegetable Harvests
Sustainable Farming Practices
Crop Planning for Sustainable Vegetable Production
Mark Cain Planning for Your CSA: www.Slideshare.net (search for Crop Planning)
Planning the Planting of Cover Crops and Cash Crops, Daniel Parson SSAWG 2012
www.slideshare.net/parsonproduce/southern-sawg
Cover Crop Innovation by Joel B Gruver www.Slideshare.net
Cover crops for vegetable cropping systems, Joel Gruver,
www.slideshare.net/jbgruver/cover-crops-for-vegetable-crops
Finding the best fit: cover crops in organic farming systems. Joel Gruver, Some overlap with previous
slideshow. www.slideshare.net/jbgruver/cover-crops-decatur
Tom Peterson Farm Planning for a Full Market Season Appalachian Farmers Market Association and
Appalachian Sustainable Development http://vabf.files.wordpress.com/2013/02/tom-peterson-
farm-planning-for-a-full-market-season.pdf
48. Resources - books
The Complete Know and Grow Vegetables, J K A Bleasdale, P J Salter et al.
Knott’s Handbook for Vegetable Growers, Maynard and Hochmuth
The New Seed Starter’s Handbook, Nancy Bubel, Rodale Books
The Organic Farmer’s Business Handbook, Richard Wiswall, Chelsea Green
Sustainable Vegetable Production from Start-up to Market, Vern Grubinger,
The New Organic Grower, Eliot Coleman, Chelsea Green
Extending the Season: Six Strategies for Improving Cash Flow Year-Round on the
Market Farm a free e-book for online subscribers to Growing for Market magazine
Sharing the Harvest, Elizabeth Henderson and Robyn Van En
Organic Farmer’s Business Handbook, Richard Wiswall
Gardening When it Counts, Steve Solomon
Grow a Sustainable Diet: Planning and Growing to Feed Ourselves and the
Earth, Cindy Conner, New Society Publishers, (worksheet based). DVD/CD set
Develop a Sustainable Vegetable Garden Plan
Crop Planning for Organic Vegetable Growers, Daniel Brisebois and Frédéric
Thériault (Canadian Organic Growers www.cog.ca)