Mixed Cropping and Intercropping – SS2 Horticulture and Crop Production Lesson Note (Second Term)

Mixed cropping and intercropping are two ways of growing two or more crops on the same piece of land at the same time.

Behavioural objectives

By the end of the lesson, students should be able to:

1. Define mixed cropping and intercropping.
2. State the difference between mixed cropping and intercropping.
3. Describe row, relay and strip intercropping.
4. List the benefits of mixing crops.
5. State the limitations of mixing crops.

What is multiple cropping?

Multiple cropping is the growing of more than one kind of crop on the same piece of land.

• Mixed cropping: crops share the land with no row arrangement.
• Intercropping: crops share the land in a definite row pattern.
• Aim: to get more from the land and to reduce the risk of losing everything.

What is mixed cropping?

Mixed cropping is the practice of growing two or more crops at the same time on the same piece of land without any specific row arrangement.

• Type of farming: the old, traditional way of growing crops.
• Planting method: seeds are scattered or planted wherever there is space.
• Appearance: the field looks jumbled, with no straight lines.
• Example: pepper, maize and okro growing together on one plot.

What is intercropping?

Intercropping is the practice of growing two or more crops at the same time on the same piece of land in a definite row pattern.

• Type of farming: the more planned, scientific way of mixing crops.
• Planting method: each crop is planted in its own rows at a set spacing.
• Appearance: the field looks neat and organised.
• Example: two rows of maize, then one row of groundnut, then two more rows of maize.

What is the difference between mixed cropping and intercropping?

The main difference is the planting arrangement: mixed cropping has no pattern, while intercropping follows a row pattern.

What are the types of intercropping?

There are three common types of intercropping: row intercropping, relay intercropping and strip intercropping.

Row intercropping

• Meaning: crops are grown in alternate rows on the same land.
• Example: maize and beans planted in alternate rows.

Relay intercropping

• Meaning: a second crop is planted after the first has started growing but before the first is harvested.
• Effect: the two crops share the land for only part of their growth.
• Example: cowpea planted into a maize field when the maize is already growing well.

Strip intercropping

• Meaning: crops are grown in wide strips, each wide enough to be worked separately.
• Effect: a tractor can pass through each strip.
• Example: a strip of maize next to a strip of groundnut.

What are the benefits of mixing crops?

The main benefit of mixing crops is that the farmer has a backup if one crop fails.

• Insurance against failure: if disease kills the tomatoes, the maize can still be harvested.
• Good use of space: a creeping crop such as melon covers the bare soil between tall maize plants and reduces weeds.
• Better soil fertility: a legume such as cowpea adds nitrogen to the soil, which helps a cereal such as maize.
• Fewer pests: the smell of one crop, such as pepper, may make it harder for insects to find another, such as cassava.
• Balanced diet: a family can harvest carbohydrate (yam), protein (beans) and vitamins (vegetables) from one small plot.
• Less soil erosion: more ground cover protects the soil from heavy rain.

What are the limitations of mixing crops?

The main limitation of mixing crops is that the plants compete with one another.

• Competition: crops planted too close compete for sunlight, water and nutrients, and one may stunt the other.
• Difficulty in mechanisation: tractors and harvesting machines may damage the smaller crops, such as pepper, while working on the maize.
• Chemical problems: a weedkiller sprayed on maize may also kill beans growing nearby.
• High labour: weeding and harvesting are mostly done by hand, which takes time and energy.
• Disease spread: a disease can pass between crops that are close together if both can catch it.

Why does mixing suit a small farm?

Mixing crops suits a small farm because one small plot can give several products.

• Protection: different plants cover the soil, add nutrients and reduce pests.
• Food supply: the farmer gets different foods from the same land.
• Limited land: a farmer with little land gets more from it by growing crops together.

Teacher’s practical note

• Task: students draw two diagrams in their notebooks.
• Diagram 1: mixed cropping, shown as random dots of different colours.
• Diagram 2: intercropping, shown as straight lines of different colours.
• Purpose: to help students see the difference between pattern and no pattern.

Evaluation

1. Define mixed cropping.
2. Define intercropping.
3. State one difference between mixed cropping and intercropping.
4. Name the three common types of intercropping and describe one of them.
5. List three benefits and two limitations of mixing crops.

Assignment

Answer both parts in your notebook:

1. Explain how mixing a cereal such as maize with a legume such as cowpea improves the soil.
2. Give three reasons why it is difficult to use machines on a mixed cropping farm.