V. COMPANION PLANTING, CROP ROTATION, AND BENEFICIALS

Companion planting, crop rotation, and the use of beneficials are ways in which you can plant crops to naturally deter pests and disease, conserve soil and space, and maintain long-term soil health. With this information you can plan out your garden.

COMPANION PLANTING:

As in human relationships plants have the habit of liking and disliking each other. For plants, this is due to their root excretions, scents, and flowers. The four main benefits of companion planting are:
1.Stronger plants
2.Insect deterrence
3.Soil conservation
4.Space conservation

Stronger Plants and Insect Deterrence:

Each plant releases different chemicals into the soil, which can either encourage or discourage the growth of particular other plants. Plants whose chemicals encourage each other’s growth are called ‘companion plants’. Plants whose chemicals discourage each other’s growth are antagonists. This is why it is important to plant vegetables next to one another that will help both to grow stronger. As the plants are strengthened they are less susceptible to pest and disease.
Insects can more easily attack a field of one type of crop than one that has many different types. Therefore, variety in each bed is a type of natural protection. Crop variation is important because your crops will be less susceptible to large disastrous invasions by a pest.

A List of Common Vegetables, Their Companions and Antagonists:

Asparagus
Companions: Tomatoes, Parsley, Basil

Beans
Companions: Almost all vegetables
Antagonists: Onions, Garlic

Beets
Companions: Onions
Antagonists: Some Beans

Cabbage Family(Cabbage, Cauliflower, Kale, African Nightshade, Broccoli)
Companions: Aromatic herbs, Potatoes, Dill, Sage, Mint, Rosemary,Beets, Onions
Antagonists: Strawberries, Tomatoes, some Beans

Carrots
Companions: Peas, Lettuce, Chives,Onions, Leeks, Rosemary,Sage, Tomatoes
Antagonists: Dill

Chives
Companions: Carrots
Antagonists: Peas, Beans

Corn
Companions: Potatoes, Peas, Beans, Pumpkin
Antagonists: Cauliflower, Cabbage

Cucumbers
Companions: Beans, Corn, Peas, Radishes, Sunflowers
Antagonists: Potatoes, aromatic herbs

Eggplant
Companions: Beans

Leeks
Companions: Onions, Carrots

Lettuce
Companions: Carrots (very good with Lettuce and Radishes), Strawberries, Cucumbers

Onions (and garlic)
Companions: Beets, Strawberries, Tomatoes,Lettuce, Parsley
Antagonists: Peas, Beans

Parsley
Companions: Tomatoes, Asparagus

Peas
Companions: Most vegetables
Antagonists: Onions, Garlic, Potatoes

Potatoes
Companions: Beans, Corn, Cabbage, Horseradish, Marigolds, Eggplant
Antagonists: Pumpkins, Squash,Cucumbers, Sunflowers, Tomatoes,

Pumpkins
Companions: Corn
Antagonists: Potatoes

Radishes
Companions: Peas, Nasturtiums, Lettuce, Cucumbers

Soybeans
Companions: Grows with anything

Spinach
Companions: Strawberries

Squash
Companions: Nasturtiums, Corn

Strawberries
Companions: Beans, Spinach, Lettuce Cabbage

Tomatoes
Companions: Chives, Onions, Parsley, Asparagus, Marigolds, Nasturtiums, Carrots
Antagonists: Potatoes, Fennel,Cabbage


Soil Conservation:

Soil conservation is achieved by what we call ‘living mulch’. The companion plants grow so close together as to create the protective qualities that mulching can provide.
1.Since the plants are placed as close to one another as possible without interfering with each other’s growth, the soil structure will be stronger and therefore more resistant to erosion
2.As your plants grow larger they will block potentially harmful rains from eroding the top layer of soil
3.Your soil will retain more water because it will be shaded more by the leaves and will not dry out as much. Because the soil stays moist it is better able to receive water without having run-off
4.Weeds will have less area to grow, and it will be more difficult for them to grow with a lack of sunlight
It is important to realize that the plants will not be able to serve this function in the early stages of growth. So, organic mulch can be used to temporarily serve the same purpose as what the living mulch will eventually be able to do. Things that can be used for mulch are any natural browns, examples are: dried leaves dried banana leaves, hay, corn husks, etc. Once the plants do become big enough to work as living mulch, the two types of mulch can work together to achieve maximum health.

Space Conservation:

Rather than planting vegetables in rows, we plant so that each plant is the same distance from the next in the diagonal offset pattern shown below. When this is done more plants can be grown than by planting in rows.



Figure 1: Hexagonal spacing-Leaf lettuce is spaced on 8'' centers

Common Plants, HF, LF, HG, and Plant Spacing:

Heavy Feaders:
African Eggplant 60cm
Amaranth (for greens) 15cm
Asparagus 30 cm
Basil 15cm
Broccoli 35cm
Chin. Cabbage 25cm
Cabbage 35cm
Comfrey, Russian 30cm
Cauliflower 35cm
Swiss Chard 20cm
Collards 28cm
Corn 40cm
Cucumbers 25cm
Eggplant 44cm
Kale 35cm
Lettuce, Head 30cm
Lettuce , Leaf 22cm
Mustard 15cm
Nightshade 20cm
Okra 15cm
Parsley 10cm
Peppers, Hot 30cm
Peppers, Sweet 30cm
Pumpkin 50cm
Shallots 10cm
Spinach 15cm
Strawberries 30cm
Swiss Chard 20cm
Sunflower 45cm
Tomatoes 40cm
Tomatoes, Cherry 40cm
Watermelon 50cm
Zucchini 45cm

Light Feeders:
Turnips 10cm
Beets 10cm
Garlic 10cm
Horseradish 28cm
Carrots 7cm
Leeks 15cm
Onions 10cm
Potato, Irish 22cm (15cm depth)
Potato, Sweet 22cm (15cm depth)
Radishes 5cm

Heavy Givers:
Peas 10cm
Beans 17cm
Soybeans 15cm





CROP ROTATION

For a number of reasons, it is good to vary the crops you plant in a plot season to season. Different plants take different nutrients and different quantities of nutrients out of the soil. Planting the same crop on the same land in succession creates soil nutrient deficiencies and also encourages insect and disease problems. The two main benefits of crop rotation are:
1.Preservation of nutrients in the soil
2.Insect deterrence

Nutrient Preservation in the Soil:

Different plants interact in different ways with the nutrients in the soil. Some take a small amount of nutrients and are called Light Feeders (LF); some take a large amount of nutrients from the soil and these are called Heavy Feeders (HF), and some plants give nutrients back to soil and they are called Heavy Givers (HG). One can’t expect to have healthy soil over time if a Heavy Feeder is planted year after year into the same soil. Crops need to be rotated so that the soil doesn’t become depleted of nutrients. Every one or two seasons the crops that you have been planting in one area should be changed. (Refer to the charts on the following pages that label each plant as LF, HF, or HG). Light feeders can follow both heavy feeders and heavy givers, but never plant two heavy feeders or two heavy givers in two consecu­tive seasons.
1.Heavy Feeders: These take large amounts of nutrients, especially nitrogen, from the soil
2.Heavy Givers: These bring large amounts of nitrogen into the soil and excrete substances, which help eradicate wilt-causing organisms
3.Light Feeders: These take small amounts of nutrients from the soil

Insect Deterrence:

Crop rotation alternates crops from one season to the next in a given field. This takes advantage of the fact that most pests are limited to feeding on one kind of crop. When the crop changes, the pests lose their host, and do not survive. This is why normally the same vegetable should not be put in the same bed each season -this invites diseases. Crop rotation is a natural way to break the pests’ feeding cycle.


List of common vegetables organized according to crop rotation and companion planting guidelines:

HEAVY GIVERS:

Beans Companions: Potatoes, Carrots, Cucumbers, Cabbage Antagonists: Onions

Bush beans Companions: Potatoes, Cucumbers, Maize, Lettuce, Tomatoes Antagonists: Onions
Peas Companions: Carrots, Cucumbers, Beans, Maize Antagonists: Onions, Potatoes

Soybeans Companions: Grows with anything and helps with anything

HEAVY FEEDERS: Companions Antagonists

Cabbage family Companions: Aromatic Plants, Potatoes, Tomatoes, Dill, Rosemary

Maize Companions: Potatoes, Peas, Beans,
Cucumbers, Pumpkins

Potatoes Companions: Beans, Maize, Cabbage, Marigolds Antagonists: Pumpkins, Cucumbers, Sunflowers

Pumpkins Companions: Maize Antagonists: Potatoes

Tomatoes Companions: Chives, Onions, Carrots,Marigolds Antagonists: Potatoes, Fennel, Cabbage


LIGHT FEEDERS:
Carrots Companions: Peas, Lettuce, Chives,Onions, Leeks, Rosemary,Tomatoes Antagonists: Dill
Chives Companions: Carrots Antagonists: Peas, Beans
Cucumbers Companions: Sunflowers, Beans, Corn, Peas, Antagonists: Potatoes,Aromatic Herbs
Leeks Companions: Onions, Carrots
Lettuce Companions: Carrots, Cucumbers
Onions Companions: Beets, Tomatoes, Lettuce Antagonists: Peas, Beans

PLANT FAMILIES

It is helpful if you understand Heavy Feeders, Light Feeders, and Heavy Givers according to the ‘plant families’. Check how the plant families below fit into the HF, LF, and HG charts above.

1.SOLANUMS
a.Tomatoes
b.Egg plants
c.Irish potatoes
d.Peppers
e.Solanum nigrum

2.LEGUMES
a.Common peas
b.Peas
c.Ground nuts
d.Green and black grams
e.Cowpeas
f.Soya beans
g.Lab beans
h.Winged beans
i.Other lesser beans

3.GRAMINACEA
a.Maize
b.Sorghum
c.Sugar cane
d.Rice
e.Oats
f.Finger millet
g.Bulrush millet
h.Wheat
i.Barley

4.CHENOPODIUM
a.Spinach (S. Oleracea)
b.Beets (Beta Vulgaris)
c.Swiss chard

5.ALLIUMS
a.Onion (spring, bunch, bulbs)
b.Leeks
c.Garlic
d.Chives

6.UMBELLIFERAE (UMBELS OR PARSELY FAMILY)
a.Carrots
b.Several herbs
1.Coriander-coriandum sativum
2.Parseley-petroselinum srispum
3.Caraway-carum
4.Pimpinella-anise anisum
5.Foeniculum-fennel vulgare
6.Anetum graveoleus-dill

7.CUCURBITS
a.Cucurbita-Pumpkin, Squash, Gourds
b.Cucumis melo-Musk melon, Melous, Cantaloupe, Cucumbers and Water melons
Chayote (Sechilim edule)

BENEFICIALS:

The following are herbs and flowers that can be included into your garden to deter insects and strengthen soil. Some deter pests, while others attract helpful insects, or lure birds and pests away from the crops. Bees and butterflies play an important part in the life cycle of plants, so a garden will benefit if it includes their favorite meals. Bees love blue flowers, especially borage and rosemary. Butterflies are attracted to purple, red, yellow, and orange flowers and will beautify our garden as well.

Other beneficial insects are attracted to the flowers of parsley, dill and cilantro/coriander. Try letting a few of those plants go to seed to serve as feeding stations for helpful insects. The perennials are best planted at the end of the beds where they will not get in the way of double digging. Another good idea is to plant beneficials like lemon grass and marigolds around the borders of your garden.

Benefits of Beneficials:
Beneficials are usually flowers or herbs that give you a natural way to make your plants more resistant to insects and to make your garden look nice at the same time
Some beneficials attract “good” insects that eat the “bad” ones: predator vs. prey. Instead of killing all the insects with pesticides, these beneficials allow good insects to help your plants
Some beneficials attract insects to themselves, luring the potential pests away from crops
Finally, some beneficials deter pests away from the garden altogether

Common Beneficials:

Basil Companion to tomatoes dislikes rue intensely - improves growth and flavor. Repels flies and mosquitoes

Chives Companion to carrots; improves growth and flavor

Dill Companion to cabbage; dislikes carrots; improves growth and health of cabbage

Fennel Plant away from gardens - most plants dislike it

Garlic Deters beetles and birds

Hyssop Deters cabbage moth; companion to cabbage

Marigolds The workhorse of the pest deterrents - plant throughout garden - discourages many insects including beetles and nematodes

Mint Companion to cabbage, and tomatoes; improves health and flavor; deters white cabbage moth

Nasturtium Companion to radishes and cabbage - plant under fruit trees - deters aphids, squash bugs, stripped pumpkin beetle. Improves growth and flavor

Petunia Protects beans

Horseradish Plant at corners of potato patch to deter potato bug

Calendula Companion to tomatoes, but plant elsewhere in the garden too - deters asparagus beetle, tomato worm, and general garden pests

Rosemary Companion to tomatoes, cabbage, beans, carrots, and sage, but plant elsewhere in garden too - deters cabbage moth, bean beetles, asparagus beetles, and carrot fly

Sage Plant with rosemary, cabbage, and carrots; keep away from cucumbers deters cabbage moth, carrot fly

Tarragon Good throughout garden

Morning Glory Allow to grow in corn - mosquito repellant

Thyme: Plant here and there in the garden - deters cabbage worms