Biointensive Mixed Plantings - Kentucky State University
1. Spacing Calculator for
Biointensive Mixed Plantings
Michael Bomford, Kentucky State University
Organic Agriculture Working Group, http://organic.kysu.edu
400 East Main Street, Frankfort, KY 40601
BACKGROUND THE PROBLEM TOOLS BASED ON MIXTURE SPACING EQUATION
Mixed planting, or companion planting, can offer • Mixed plantings spaced according
benefits over monocultures: to Jeavons’ recommendations
• Mixed crops often have higher yields than require more land than separate SPACING CALCULATOR
monocultures because different species use monoculture beds when: SPREADSHEET
different resources, making more efficient use of – One crop is much larger than the • Select options from drop-down menus:
land.1 other
– 1. Use pure stand spacing
– The smaller crop makes up a
• Mixed plantings often have fewer pest problems recommendations from Jeavons,4 Rodale
larger proportion of the plants
than monocultures because pests have a harder Institute,6 University of Kentucky
than the larger crop
time finding suitable hosts, or because diverse Extension,7 or another favorite source Mixture Snap bean
• If mixtures use resources more – 2. Choose a primary and secondary crop
100 (pole)
Corn
plantings provide better habitat for natural 75
efficiently than monocultures they (spreadsheet limited to two-crop mixtures)
enemies.2
cm
50
should not need more space. – 3. Select the number of secondary crop 25
• Diversity helps reduce risk. Promoting
plants per primary crop plant in mix (crop 0
biodiversity is a stated goal of the USDA's ratio)
0 25 50
cm
75 100
national organic standards.3
• Spreadsheet calculates (in metric and US
Corn Snap bean (pole)
100 100
Some crops are commonly grown in mixtures: measurement units): 75 75
• Hay is usually a mix of grass and legume
cm
cm
50 50
– Spacing between plants
species.
25 25
– Spacing between offset rows 0 0
• Shade-grown coffee plantations mix low-growing – Crop ratio that dedicates an equal amount
0 25 50
cm
75 100 0 25 50
cm
75 100
coffee bushes with trees. of land to each crop The spacing calculator spreadsheet
• Backyard gardeners often mix vegetables, herbs, – Planting density for component crops and generates planting diagrams for
and flowers in the same bed. mixture mixtures based on pure-stand plant
Although mixed plantings are common, practical – Much more… spacing for component crops.
resources for those who grow mixed crops are Two-crop companion planting Download: http://organic.kysu.edu/CompanionSpacing.shtml
few; production guides and extension materials diagram with dimensions, adapted
often assume monoculture. from How to Grow More
Vegetables... Corn plants are
represented by yellow circles; beets
are red. A mixture of 33 corn plants ONLINE SPACING Corn Beans Squash
and 80 beet plants requires 60 sq. ft. CALCULATOR
BIOINTENSIVE MINI-FARMING • Requires
– Recommended spacing
• How to Grow More Vegetables… by John
for pure stand
Jeavons4 advocates a gardening system
(up to four crops)
called "biointensive mini-farming," which
consists of: – Relative proportion of
– deeply-cultivated (“double dug”) beds crops in mixture
amended with compost • Delivers
– high-density mixed plantings – Between-plant spacing for
– offset rows evenly-spaced mixture
(every plant is the same distance from its
six nearest neighbors, creating a beehive – Between-clump spacing for If each hill has 4 corn plants, 4 bean
pattern of hexagons) clumped mixture plants and 1 squash plant then hills
should be spaced 37” apart.
The same number of plants grown in two
pure stands would require only 53 sq. ft. SF SF
B
SF SF
C
of bed space, leaving 7 sq. ft. for another SF
SF B C
C
C B SF
SF
crop SF B
SQ
SF
SF
SF
B
C
B
C
B
C
37” B
C SF
B C C B B C C B B C C B B C C B
SF C C C C SF
B B B B
B SQ B SQ B SQ B SQ
37”
B
C C C C C
B C C B B C C B B C C B B C C B B C C B
A SOLUTION C
B
C
B
C
B
C
B
C
B
For plant spacing in mixtures, • An equation5 can be used to
B
C
SQ B
C
SQ B
C
SQ B
C
SQ B
C
SQ B
C
Hexagonal spacing diagram from Jeavons uses the mean of his B C C B B C C B B C C B B C C B B C C B B C C B
calculate between-plant spacing C C C C C C
How to Grow More Vegetables... The recommended plant spacings for
B B B B B B
for mixtures (smix) from: Example: The Wampanoag people SQ
B
SQ
B
SQ
B
SQ
B
SQ
B
SQ
spacing between plants is equivalent component crops. For example, he C C C C C
– The recommended spacing for traditionally planted circular gardens of corn B C C B B C C B B C C B B C C B B C C B
within and between rows, forming a suggests that corn plants in
C C C C C
each component crop in pure and beans in clusters of four in evenly-spaced B B B B B
hexagonal lattice of tightly-spaced monoculture be spaced 15" apart, stands (sA, sB…)
SQ B SQ B SQ B SQ B SQ
mounds. A squash plant was grown by each C C C C
plants. and beet plants 4" apart, so corn B C C B B C C B B C C B B C C B
– The proportion of the mixture mound. The online spacing calculator can be used C C C C
B B B B
and beet planted as a mixture are accounted for by each to calculate inter-clump spacing for clumped mixtures SQ SQ B SQ SQ
spaced 9.5" ([15+4]/2) apart. component crop (pA, pB…). C
like this from recommended spacing for pure stands. B C
C
C B
B
2 2
smix = p A s A + pB sB + ... Try it: http://organic.kysu.edu/CompanionSpacingCalculator.shtml
• Mixtures spaced using this
equation use the same amount of 1.
2.
P.A. Jolliffe. 1997. Are mixed populations of plant species more productive than pure stands? Oikos 80: 595-602.
H.A. Smith & R. McSorley. 2000. Intercropping and pest management: A review of major concepts. American Entomologist 40: 154-161.
land as if the component plants 3.
4.
USDA National Organic Program. 1999. Definitions -- Regulatory Text. http://www.ams.usda.gov/NOP/NOP/standards/DefineReg.html
J. Jeavons. How to Grow More Vegetables Than You Ever Thought Possible on Less Land Than You Can Imagine. Ten Speed Press,
were divided into pure stands 5.
Berkeley CA, 2006.
M.K. Bomford. 2009. Do tomatoes love basil but hate Brussels sprouts? Competition and land-use efficiency of popularly recommended
and discouraged crop mixtures in biointensive agriculture systems. Journal of Sustainable Agriculture 33 (4): In press.
6. F.M. Bradley & B.W. Ellis. Rodale's All-New Encyclopedia of Organic Gardening. Rodale Press, Emmaus PA, 1992.
7. B. Rowell, R. Bessin, J. Masabni, J. Strang, T. Jones, & K. Seebold. 2006-07 Vegetable Production Guide for Commercial Growers.
University of Kentucky Cooperative Extension Service, Lexington KY, 2007