All You Need To Know About Companion Planting
In the face of climate change, soil degradation, and rising pest infestations, farmers and gardeners are turning to sustainable and traditional agricultural methods to improve productivity and resilience.
One such technique gaining ground is companion planting.
Rooted in indigenous knowledge and supported by modern agricultural science, companion planting offers a natural way to boost crop yields, manage pests, and enrich soil health without relying heavily on chemical inputs.
This article delves into the concept of companion planting, highlighting its benefits, limitations, and practical applications for farmers across the country.
What is Companion Planting?
Companion planting refers to growing different crops close to each other to promote mutual benefits.
These benefits include pest control, enhanced pollination, improved nutrient uptake, and better space utilisation.
Unlike monoculture, which involves planting a single crop type over a large area, companion planting fosters a biodiverse ecosystem in a farm or garden.
This technique draws from both ancient agricultural practices and modern ecological principles.
For example, in our traditional farming systems, crops like maize, cassava, and melon (Egusi) are intercropped to take advantage of their complementary growth habits.
Some alternative names or terms often used for companion crops are:
- Supporting crops – Highlighting their role in assisting the main crop.
- Symbiotic plants – Refers to the mutually beneficial relationship between crops.
- Beneficial intercrops – Especially when referring to intercropping setups with ecological advantages.
- Helper plants – Emphasise their role in aiding pest control or soil enrichment.
- Protective plants – Used when the crop is specifically planted to ward off pests or diseases.
- Trap crops – These are planted near a main crop to lure pests away.
- Plant allies – A broader, more informal term to describe plants that benefit each other.
- Agroecological pairs – In academic or technical contexts, this refers to crops paired based on ecological principles.
Difference Between Companion Planting and Intercropping
While companion planting and intercropping are often used interchangeably, they have distinct differences:
- Purpose: Companion planting is specifically designed to achieve certain ecological or horticultural benefits such as pest control, pollination, and nutrient enhancement. Intercropping, on the other hand, focuses primarily on maximising land productivity by growing two or more crops together.
- Plant Selection: Companion planting relies on the relationship between plant species (such as scent leaf repelling pests for tomatoes). Intercropping does not necessarily consider mutual benefits beyond space and resource optimisation.
- Design Complexity: Companion planting involves strategic pairings based on plant interactions, while intercropping can be as simple as growing two crops together with minimal interaction considerations.
- Examples:
- Companion Planting: Tomato and scent leaf to repel pests.
- Intercropping: Maize and beans to maximise yield and space.
Both methods can be complementary, and farmers often use elements of both depending on their goals and available resources.
Advantages of Companion Planting
- Natural Pest Control: Certain plants repel pests that are harmful to their neighbours. For example, onions can repel aphids that commonly attack carrots.
- Soil Enrichment: Leguminous plants like beans and green peas fix nitrogen in the soil, benefiting neighbouring crops that require high nitrogen levels.
- Efficient Use of Space: By pairing tall and short crops, or deep-rooted and shallow-rooted plants, farmers can maximise land use.
- Improved Crop Health: The diversity of plant species can reduce disease spread and increase crop resilience.
- Increased Yield: Well-planned companion planting can lead to better overall yield from a given plot of land.
- Weed Suppression: Dense or ground-cover crops like sweet potatoes suppress weed growth by blocking sunlight.
Disadvantages of Companion Planting
- Complex Planning: Companion planting requires knowledge and careful planning. Mistakes can lead to competition for nutrients, water, and light.
- Labour Intensive: Managing diverse crops in the same plot can require more labour, especially in weeding and harvesting.
- Pest Habitat Risk: In some cases, if not properly managed, a mixed planting can harbour pests and diseases.
- Limited Mechanisation: Using machinery in companion planting setups is often difficult due to the irregular planting patterns.
How Does Companion Planting Help with Pest Control?
Companion planting creates a diversified environment that confuses pests or makes the environment hostile to them. For instance:
- Onions and garlic produce strong odours that deter aphids, caterpillars, and beetles.
- Scent leaf, when planted near tomatoes, repels whiteflies and hornworms.
- Marigold flowers are often planted near vegetables because they emit a scent that repels nematodes and other soil-borne pests.
This natural method of pest control reduces the need for chemical pesticides, which can be expensive and harmful to the environment.
How Does It Enhance Nutrient Availability?
Some plants have unique nutrient interactions with the soil. For example:
- Legumes (beans, green peas) fix atmospheric nitrogen through symbiosis with root bacteria. This nitrogen enriches the soil and benefits nearby heavy feeders like tomatoes and maize.
- Deep-rooted plants like carrots can bring nutrients from lower soil layers up to the surface, indirectly feeding shallow-rooted neighbours.
By strategically placing these types of plants together, nutrient cycling within the soil improves, leading to healthier crops and reduced need for synthetic fertilisers.
How to Determine Which Crops Can Be Planted Together
To plan effective companion planting, consider the following factors:
- Nutrient Needs: Pair plants with complementary nutrient demands. For example, avoid planting two heavy feeders like cabbage and maize together.
- Growth Habits: Combine tall plants that offer shade with shade-tolerant crops. For instance, maize can provide shelter for cucumbers.
- Root Depth: Pair shallow-rooted crops with deep-rooted ones to minimise competition.
- Pest Susceptibility: Avoid grouping crops susceptible to the same pests and diseases.
- Allelopathy: Some plants release chemicals that inhibit the growth of others. For example, avoid planting onions near beans due to potential allelopathic effects.
Which Vegetables Should Not Be Planted Together and Why
Certain vegetables do not make good companions due to competition or adverse chemical interactions. Examples include:
- Tomato and Potato: Both are from the nightshade family and are susceptible to similar pests and diseases like blight.
- Onion and Beans: Onions can stunt the growth of beans due to allelopathic effects.
- Cabbage and Eggplant: They compete for nutrients and attract similar pests like flea beetles.
Avoiding these combinations can help reduce pest issues and promote healthy growth.
What Are the Best Companion Plants?
Some of the most effective companion plant combinations include:
- Maize + Beans + Pumpkin(Ugbogoro): A traditional trio where maize provides support for beans, beans enrich the soil, and pumpkin suppresses weeds.
- Tomato + Scent leaf: Scent leaf repels pests and enhances the flavour of tomatoes.
- Onion + Carrot: Onions repel carrot flies, and carrots deter onion flies.
- Cabbage + Onion: Onions deter cabbage worms and other pests.
Companion Planting Table for Nigerian Crops
| Plant | Companion Plants | Plants to Avoid |
|---|---|---|
| Pepper | Scent leaf, onions, carrots, spinach, tomatoes | Beans, cabbage family plants (e.g cabbage, broccoli), fennel |
| Tomato | Carrots, lettuce, strawberries, beets, onions, scent leaf | Cabbage, corn, potato |
| Cucumber | Beans, corn, sunflower | Potatoes, aromatic herbs (strong-scented) |
| Okra | Peppers, basil, spinach, lettuce | None major, avoid overcrowding |
| Beans | Corn, cucumber, carrot, potato, lettuce | Onion, garlic, leeks |
| Onion | Tomato, Cabbage family (cabbage, broccoli, kale), lettuce, beetroot, amaranth (green) | Beans, peas |
| Carrot | Onion, leek, lettuce, and tomatoes | Dill, fennel |
| Cabbage | Onion, garlic, dill, potatoes | Tomato, strawberry, beans |
| Eggplant | Tomato, cucumber, and pumpkin | Fennel |
| Potato | Beans, corn, cabbage | Tomato, cucumber, pumpkin |
| Sweet Potato | Beans, thyme | Tomato |
| Watermelon | Corn, sunflowers | Potatoes, cucumber |
| Corn/Maize | Beans, pumpkin, cucumber | Tomato |
| Green Pea | Carrot, radish, corn | Onion, garlic |
| Ugu (Fluted Pumpkin) | Corn, okra, melon | Strong aromatic herbs |
| Lettuce | Carrot, onion, beet | Parsley, cabbage |
| Cloves | Garlic, turmeric | Avoid planting too close to legumes |
| Scent Leaf | Tomato, pepper, eggplant | |
| Bitter Leaf | Yams, maize | Avoid water-heavy plants |
| Water Leaf | Pepper, tomatoes | Onions, garlic |
| Curry Leaf | Basil, turmeric | Moisture-loving plants |
| Okazi | Palm trees (indirectly), shade plants | Heavy feeders |
| Uziza | Pepper, scent leaf | |
| Utazi | Bitter leaf, okra | |
| Spinach | Pepper, onion, eggplant | None major |
| Green (Amaranth) | Okra, beans, maize | None major |
| Jute (Ewedu) | Corn, okra, water leaf | Onion |
| Lagos Spinach | Tomatoes, peppers | None documented |
| Pumpkin (Ugbogoro) | Corn, beans, watermelon | Potato, cucumber |
| Melon (Egusi) | Corn, okra, beans | Onion, potato |
| Ginger | Spinach, beans, lettuce | Onions |
| Turmeric | Ginger, beans, lemongrass | Garlic |
| Lemongrass | Turmeric, ginger, basil | Moisture-loving herbs |
| Garlic | Tomato, carrot, cabbage | Beans, peas |
| Beet | Lettuce, onions, cabbage | Pole beans |
| Sunflower | Cucumber, corn | Potato |
| Cassava | Maize, melon, cowpea | Legumes (close planting may inhibit) |
| Yam | Okra, maize, melon | Onions |
| Water Yam | Maize, legumes | Heavy feeders |
| Three-leaved Yam | Cassava, maize | Strong-rooted shrubs |
| Garden Egg | Pepper, tomato, scent leaf | Fennel |
| Groundnut | Maize, yam, cassava | Onion, garlic |
| Pineapple | Beans, groundnut, lemongrass | Potato |
| Thyme | Tomato, cabbage, rosemary | Beans, chilli, turmeric |
| Aloe Vera | Tomato, onions | Moisture-heavy crops |
| Plantain | Beans, okra, cassava | Water-loving crops |
| Banana | Sweet potato, beans, maize | Onion |
| Strawberry | Spinach, bean, lettuce | Cabbage, broccoli |
| Millet | Beans, groundnut | Sorghum |
| Sorghum | Beans, groundnut | Millet |
| Wheat | Onion, garlic, lettuce | Tomato |
Conclusion
Companion planting is a sustainable agricultural technique that offers immense potential for improving crop yields, managing pests naturally, and enriching the soil.
This method can be tailored to suit various ecological zones and farming styles in Nigeria, where diverse climatic conditions and soil types exist.
With proper planning and knowledge, farmers can adopt companion planting to build more resilient farming systems.
As agricultural challenges mount, integrating age-old wisdom with modern techniques like companion planting is not just beneficial, it’s essential.
.“Companion planting works wonders—but which combos work best for you? Drop your go-to pairings below!
