Transcript Companion Planting: Basic Concept and Resources Research & compiled by Camille Leblanc

Companion Planting:
Basic Concept and Resources
Research & compiled by Camille Leblanc
While companion planting has a long history, the
mechanisms of beneficial plant interaction have not
always been well overstood. Traditional
recommendations used by gardeners have evolved from
an interesting combination of historical observation,
horticultural science, and a few unconventional sources.
Traditional Companion Planting
Companion planting can be described as the
establishment of two or more plant species in
close proximity so that some cultural benefit
(pest control, higher yield, etc.) is derived.
The concept embraces a number of strategies
that increase the biodiversity of agro
ecosystems.
Table 1. COMPANION PLANTING CHART FOR HOME &
MARKET GARDENING (compiled from traditional literature on
companion planting)
CROP
COMPANIONS
INCOMPATIBLE
Asparagus
Tomato, Parsley, Basil
Beans
Most Vegetables & Herbs
Beans, Bush
Irish Potato, Cucumber, Corn, Onion
Strawberry, Celery, Summer
Savoury
Beans, Pole
Corn, Summer Savoury,
Radish
Onion, Beets,
Kohlrabi, Sunflower
Cabbage
Family
Aromatic Herbs, Celery,
Beets, Onion Family,
Chamomile, Spinach, Chard
Dill, Strawberries,
Pole Beans, Tomato
Carrots
English Pea, Lettuce,
Rosemary, Onion Family,
Sage, Tomato
Dill
Celery
Onion & Cabbage Families,
Tomato, Bush Beans,
Nasturtium
Corn
Irish Potato, Beans, English
Pea, Pumpkin, Cucumber,
Squash
Tomato
Cucumber
Beans, Corn, English Pea,
Sunflowers, Radish
Irish Potato,
Aromatic Herbs
Eggplant
Beans, Marigold
Lettuce
Carrot, Radish, Strawberry,
Cucumber
Onion Family Beets, Carrot, Lettuce,
Cabbage Family, Summer
Savory
Beans, English Peas
Parsley
Tomato, Asparagus
Pea, English
Carrots, Radish, Turnip,
Cucumber, Corn, Beans
Onion Family,
Gladiolus, Irish
Potato
Potato, Irish
Beans, Corn, Cabbage
Family, Marigolds,
Horseradish
Pumpkin, Squash,
Tomato, Cucumber,
Sunflower
Pumpkins
Corn, Marigold
Irish Potato
Radish
English Pea, Nasturtium,
Lettuce, Cucumber
Hyssop
Spinach
Strawberry, Faba Bean
Squash
Nasturtium, Corn, Marigold
Irish Potato
Tomato
Onion Family, Nasturtium,
Marigold, Asparagus, Carrot,
Parsley, Cucumber
Irish Potato, Fennel,
Cabbage Family
Turnip
English Pea
Irish Potato
Trap Cropping
Sometimes, a neighbouring crop may be
selected because it is more attractive to pests
and serves to distract them from the main
crop. An excellent example of this is the use
of collards to draw the diamond back moth
away from cabbage.
Symbiotic Nitrogen Fixation
Legumes such as peas, beans, and clover have
the ability to fix atmospheric nitrogen for their
own use and for the benefit of neighbouring
plants via symbiotic relationship with
Rhizobium bacteria. Forage legumes, for
example, are commonly seeded with grasses to
reduce the need for nitrogen fertilizer. Likewise,
beans are sometimes interplanted with corn.
Biochemical Pest Suppression
Some plants exude chemicals from roots or aerial parts
that suppress or repel pests and protect neighbouring
plants. The African marigold, for example, releases
thiopene—a nematode repellent—making it a good
companion for a number of garden crops. The
manufacture and release of certain biochemical's is also a
factor in plant antagonism. Allelochemicals such as
juglone—found in black walnut—suppress the growth of
a wide range of other plants, which often creates a
problem in home horticulture. A positive use of plant
allelopathy is the use of mow-killed grain rye as a mulch.
The allelochemicals that leach from rye residue prevent
weed germination but do not harm transplanted
tomatoes, broccoli, or many other vegetables.
bi·o·chem·i·cal relating to biochemistry: relating to the chemical substances present in living
organisms and the reactions and methods used to identify or characterize
an·tag·o·nism 1. hostility: hostility or hatred causing opposition and ill will
3. physiology neutralizing interaction: the interaction between two or more chemical substances
that diminishes the effect each of them has individually
al·le·lo·chem·i·cal toxic plant chemical: a chemical produced by one plant that is toxic to
another. Also called allelotoxin
al·le·lop·a·thy
suppression of neighboring plants: the release into the environment by one plant of a substance
that inhibits the germination or growth of other potential competitor plants of the same or another
species
Physical Spatial Interactions
For example, tall-growing, sun-loving plants may
share space with lower-growing, shade-tolerant
species, resulting in higher total yields from the land.
Spatial interaction can also yield pest control
benefits. The diverse canopy resulting when corn is
companion-planted with squash or pumpkins is
believed to disorient the adult squash vine borer and
protect the vining crop from this damaging pest. In
turn, the presence of the prickly vines is said to
discourage rodents from ravaging the sweet corn.
Nurse Cropping
Tall or dense-canopied plants may protect more
vulnerable species through shading or by
providing a windbreak. Nurse crops such as oats
have long been used to help establish alfalfa and
other forages by supplanting the more
competitive weeds that would otherwise grow in
their place. In many instances, nurse cropping is
simply another form of physical-spatial
interaction.
al·fal·fa forage crop: a European and Asian plant in the pea family, widely grown as a hay and
forage crop.
oat grass with edible seed: a grass that has edible seeds and is grown in numerous northern
countries as a cereal crop
spa·tial relating to space: relating to, occupying, or happening in space
Beneficial Habitats
Beneficial habitats—sometimes called refugia—are another type of
companion plant interaction that has drawn considerable attention in
recent years. The benefit is derived when companion plants provide a
desirable environment for beneficial insects and other arthropods
especially those predatory and parasitic species which help to keep pest
populations in check. Predators include ladybird beetles, lacewings
hover flies, mantids, robber flies, and non-insects such as spiders and
predatory mites. Parasites include a wide range of fly and wasp species
including tachinid flies, and Trichogramma and ichneumonid wasps.
Agro ecologists believe that by developing systems to include habitats
that draw and sustain beneficial insects, the twin objectives of reducing
both pest damage and pesticide use can be attained. For detailed
information on establishing beneficial habitats, request the ATTRA
publication Farmscaping to Enhance Biological Control.
ar·thro·pod
invertebrate animal: an invertebrate animal that has jointed limbs, a segmented body, and an
exoskeleton made of chitin. Insects, arachnids, centipedes, and crustaceans are arthropods.
Security Through Diversity
A more general mixing of various crops and
varieties provides a degree of security to the
grower. If pests or adverse conditions reduce
or destroy a single crop or cultivar, others
remain to produce some level of yield.
Furthermore, the simple mixing of cultivars,
as demonstrated with broccoli in University
of California research, can reduce aphid
infestation in a crop.
COMPANION VEGETABLE GARDENING
It's said that vegetables are like people, they thrive
on companionship. It is believed that vegetables will
yield up to twice as much when they are surrounded
with companion plants. So in this article we will
discuss the top 12 vegetables and their best friends.
If you're getting ready to plant your vegetable garden
you may want to try placing the various vegetable
crops so you can take advantage of their natural
friends. If you have already planted your vegetable
garden you may want to make some changes in
subsequent plantings later this summer.
The following are a list of the top
12 vegetables and their ideal
planting companions.
Beans--they like celery and cucumbers but dislike onions and
fennel.
Beets--Bush beans, lettuce, onions, kohlrabi, and most
members of the cabbage family are companion plants. Keep
the pole beans and mustard away from them.
Cabbage--Celery, dill, onions and potatoes are good
companion plants They dislike strawberries, tomatoes, and
pole beans.
Carrots--Leaf lettuce, radish, onions and tomatoes are their
friends, Plant dill at the opposite end of the garden.
Corn--Pumpkins, peas, beans, cucumbers and potatoes are
nice companion plants, Keep the tomatoes away from them.
Cucumbers--They like corn, peas, radishes, beans and
sunflowers. Cucumbers dislike aromatic herbs and potatoes
so keep them away.
Lettuce--It grows especially well with onions.
Strawberries carrots, radishes and cucumbers
also are friends and good companion plants.
Onions--Plant them near lettuce, beets,
strawberries and tomatoes but keep them
away from peas and beans.
Peas--Carrots, cucumbers, corn, turnips and
radishes plus beans, potatoes and aromatic
herbs are their friends. Keep the peas away
from onions, garlic, leek, and shallots
Radishes--This is one vegetable that has a lot of
friends, they are excellent companion plants with
beets, carrots, spinach and parsnips. Radishes grow
well with cucumbers and beans. It's said that summer
planting near leaf lettuce makes the radishes more
tender. Avoid planting radishes near cabbage,
cauliflower, Brussels sprouts, broccoli, kohlrabi or
turnips.
Squash--Icicle radishes, cucumbers and corn are
among their friends.
Tomatoes--Carrots, onions and parsley are good
companion plants. Keep the cabbage and cauliflower
away from them.
Sometimes plant friendships are one-sided. Carrots are said to
help beans, but beans don’t reciprocate. Though beans will
help nearby cucumbers.
Other plants have bad companions and you'll be doing them a
favour to keep them apart. Beans and onions are natural
enemies so keep them at opposite sides of the garden.
If you have a patio you might try mint to repel ants, and basil
to keep the flies and mosquitoes away. Both herbs have pretty
flowers and are fragrant too. Besides, they're nice to harvest
and use in the kitchen. "Carrots Love Tomatoes" getting to
know good and bad companions can double the bounty of
your garden. The only required work is to plan your garden
planting properly.
Herb Companion Chart
The idea that herbs make good companion plants is
not new. Some of the earliest written documents on
gardening discuss these relationships. When selecting
your companion plants you will need to consider more
than which pests are deterred. Think about what each
plant adds or takes away from the soil and what effect
the proximity of strong herbs may have on the flavour
of your vegetables. Try to avoid placing two heavy
feeders or two shallow rooted plant types near each
other.
Herb
Chives
Companions
Carrots
Basil
Tomatoes
Dead
Nettle
Potatoes
Dill
Pests Repelled
Cabbage
Dislikes Carrots
Flies, Mosquitoes
Potato Bug
Garlic
Marigolds
Fennel
Mint
Roses, Raspberries
Plant throughout the garden
Japanese Beetle, Aphids
Mexican Bean Beetles,
Nematodes, others
Most plants dislike this herb
Cabbage, Tomatoes
White Cabbage Moth,
aphids, flea beetles
Sage
Thyme
Rosemary, Cabbage, Carrots
Dislikes Cucumbers
Cabbage
Cabbage Moth, Carrot Fly,
Flea Beetle, Slugs
Cabbage Worm
Pot
Marigold
Tomatoes
Tomato Worm, Asparagus Beetles,
others
Rosemary
Cabbage, Beans Carrots, Sage
Cabbage Moth, Bean Beetle, Carrot
Fly
Companion planting practices
• The following are some examples of
farming in the village of Cochrane where
companion planting is practiced
traditionally with herbs & vegetables
Herbs & vegetables plot #1
Farmer of plot
Extension Off. Examining plot
Vegetable plot #2
Asparagus & Flowers
Farmer harvesting crop
Compost pit
Farmer harvesting
Companion of cane & marigold
Harvest Time
• We have come to harvest time remember in
organic planting always make certain you
know what your companion crops are in the
field, this will lead to reduce crop damage
through pest & diseases.
• Remember organic farming is a process not
a past time. Have fun.
Researched & compiled by Camille Leblanc