Planting Operations – SS1 Horticulture and Crop Production Lesson Note (Third Term)

Planting is the operation of placing seeds or planting materials in prepared soil at the right time, depth and spacing so that they can germinate and grow well.

Behavioural objectives

1. Explain why timing, depth and spacing matter in planting.
2. Describe early planting and late planting, with one benefit or risk of each.
3. State the general rule for planting depth and give examples for small, medium and large seeds.
4. Distinguish between within-row and between-row spacing and give reasons for spacing plants.
5. State typical spacing, depth and timing for maize, okra, cowpea and yam.

What makes planting successful?

Planting is successful when a horticulturist gets timing, depth and spacing right after the land is cleared, ploughed and ridged.

1. Timing: when to plant.
2. Depth: how deep to place the seed or planting material.
3. Spacing: how much room to give each plant.

• Too deep: the seedling may be unable to push out of the soil.
• Too crowded: the plants cannot grow well.
• Wrong time: the seeds may not get enough moisture.

What are the methods of planting?

There are three common methods of planting: direct sowing of seeds, transplanting of seedlings and vegetative planting.

• Direct sowing: seeds are sown straight into the field, as in maize, cowpea and okra.
• Transplanting: seedlings raised in a nursery are moved to the field, as in tomato, pepper and cabbage.
• Vegetative planting: parts of a plant are planted, such as yam setts, cassava stem cuttings and plantain suckers.

How can seeds be sown directly?

• Broadcasting: seeds are scattered by hand over the whole plot.
• Drilling: seeds are dropped in a continuous line along a furrow or ridge.
• Dibbling: holes are made at set distances and seeds are placed in each hole.

When should crops be planted?

Crops should be planted when the soil has enough moisture, which in Nigeria depends on the rains.

• Seeds need moisture to germinate (start to grow).
• Timing is therefore the most important of the three factors.

What is early planting?

Early planting is sowing at the start of the rainy season, usually March or April in the South.

• Benefit: the crop uses the full rainy season and may be ready for harvest when food prices are high.
• Risk: if the rains stop suddenly (a break in the rains, often called the “April drought”), young plants may die.

What is late planting?

Late planting is sowing towards the end of the rains, usually August or September.

• Benefit: it suits crops that need dry weather to ripen, such as cowpea (beans).
• Risk: the rains may end before the crop has matured.

What time of day should seedlings be planted?

Tomato, pepper and other seedlings should be transplanted early in the morning or late in the evening.

• Reason: the afternoon sun is hot and makes young plants lose water and wilt.
• Result: cool hours help the seedlings settle in and recover.

How deep should seeds be planted?

The general rule is that the smaller the seed, the shallower the hole.

Why does depth matter?

• Too deep: the seedling uses up its stored food pushing through the soil and may die before it reaches the light.
• Too shallow: birds may eat the seed, or the sun may dry it out before it grows.

What are examples of planting depth?

What is spacing in planting?

Spacing is the distance between one plant and the next, measured in two ways.

• Within-row spacing: the distance between plants on the same ridge or row.
• Between-row spacing: the distance between one ridge or row and the next.

Why do we space plants?

• To reduce competition: plants share water, nutrients and light, so each needs enough room.
• Air flow: breeze moves between plants and helps prevent diseases caused by fungi.
• Easy movement: the farmer can walk through the crop, weed and spray without damaging plants.

What happens when spacing is wrong?

What are the typical planting measurements for common crops?

Every crop has its own spacing, depth and best planting time, as this guide for common Nigerian crops shows.

What are the steps in planting a crop?

Planting follows a fixed order of steps.

1. Check that the soil is moist and the time of planting is right.
2. Mark the spacing on the ridges with a measuring tape or rope and pegs.
3. Make holes of the correct depth with a hoe or dibber.
4. Place 2 or 3 seeds in each hole.
5. Cover the seeds with soil and press lightly.
6. Replace any seeds that fail to germinate (supplying or gap filling).
7. Thin the seedlings later, leaving the strongest plant in each hole.

Practical planting tips

• The “water first” rule: plant only in moist soil, because planting in bone-dry soil wastes seeds.
• Seeds per hole: 2 or 3 seeds are planted in case some fail to germinate.
• Thinning: if all the seeds grow, the weakest seedlings are removed to leave the strongest.

Evaluation

1. Name the three things a horticulturist must master for successful planting.
2. State one benefit and one risk of early planting.
3. Why do we plant tomatoes and peppers early in the morning or late in the evening?
4. State the general rule for planting depth and give one example of a small seed and one of a medium seed.
5. Give three reasons for spacing plants.

Assignment

Explain the difference between within-row and between-row spacing. Using the table, state the spacing, depth and best timing for maize and cowpea. Explain why we plant 2 or 3 seeds per hole and then thin the seedlings.