Unlocking the Secrets of Stem Propagation

Unlocking the Secrets of Stem Propagation

Learning Objective

At the end of the lesson, you will be able to understand the structure of stems, the different stem propagation techniques, and the importance of stem cuttings in horticulture.

What do you already know about stem structure and its importance in horticulture?

Stem Structure

The stem is the main structural part of a plant that supports leaves, flowers, and fruits. It consists of various components, including xylem, phloem, cambium, and pith.

Xylem and Phloem

Xylem is responsible for transporting water and nutrients from the roots to the rest of the plant. Phloem, on the other hand, transports sugars and other organic materials from the leaves to other parts of the plant.

Copy and paste this link into google to look at the xylem and phloem
https://www.saps.org.uk/teaching-resources/resources/1299/biology-animations-transport-of-water-and-sugar-respiration-and-photosynthesis-and-cell-growth-in-plants/

Cambium and Pith

Cambium is a layer of cells that produces new cells for both xylem and phloem. Pith, located at the center of the stem, provides support and stores nutrients

If you look at this tree trunk cross
section, you can see how it is
structured

Stem Cuttings: Hardwood

Hardwood cuttings are taken from mature, dormant stems during late winter or early spring. They have a higher chance of rooting successfully

Stem Cuttings: Softwood

Softwood cuttings are taken from young, flexible stems during the active growth period. They root quickly but require more attention.

Stem Cuttings: Tip and Inter-nodal

Tip cuttings involve taking the terminal portion of a stem, while inter-nodal cuttings are taken from the space between two nodes. Both types have specific uses in 

Transpiration and Stem Cuttings

Transpiration is the process of water loss through plant leaves. When taking stem cuttings, reducing transpiration helps prevent excessive water loss and aids in successful rooting

Cutting Techniques: Leaf Removal and Angle

Cutting leaves in half or removing them completely reduces transpiration. Cutting stems at a 45-degree angle increases the surface area for water absorption and minimizes rotting in the compost.

Using a sharp knife or blade also reduces crushing the cells and causing rotting of the roots and promote better root growth. 

How are stem structure and leaf structure linked in horticulture?

1. Stem structure affects root growth
2. They both play a role in transpiration
3. Leaf structure determines flower color
4. They are completely unrelated

Why do we cut the stems at a 45 degree angle when taking cuttings?

1. To promote flowering
2. To reduce water loss and prevent rotting
3. To improve leaf structure
4. To increase root growth

Why do we reduce the rate of transpiration when taking stem cuttings?

1. To increase plant growth
2. To prevent excessive water loss
3. To enhance photosynthesis
4. To improve stem structure

Which type of stem cutting is taken from mature, woody plants?

1. Internodal cutting
2. Hardwood cutting
3. Softwood cutting
4. Tip cutting

What are the components of stem structure?

1. Xylem, phloem, cambium, pith
2. Leaves, roots, flowers, bark

How does cutting stems at a 45-degree angle help?

1. To facilitate stem bending
2. To promote shoot growth
3. To increase surface area for rooting
4. To prevent water pooling

Why is reducing transpiration important for stem cuttings?

1. To increase root growth
2. To enhance leaf development
3. To prevent excessive water loss
4. To maintain moisture

What is the purpose of taking tip cuttings?

1. To promote branching
2. To produce new plants
3. To reduce transpiration
4. To increase stem growth

When are hardwood cuttings taken?

1. In spring
2. During active growth
3. In winter
4. During dormancy

Why do we use a sharp blade to take stem cuttings?

1. To prevent diseases in the plants
2. To create a clean cut that promotes root growth
3. To increase the chances of flowering
4. To make the process easier and faster

Linking Stem and Leaf Structure

Stem and leaf structures are interconnected as the stem provides support and transports water and nutrients to the leaves. Understanding their relationship is crucial in horticulture as it helps in plant propagation and overall plant health.

How is stem and leaf structure linked?

Write down 3 things you learned in this lesson.

Have students enter three things they learned in this lesson. With this they can indicate their own learning efficiency of this lesson.

Write down 2 things you want to know more about.

Here, students enter two things they would like to know more about. This not only increases involvement, but also gives them more ownership.

Ask 1 question about something you haven't quite understood yet.

The students indicate here (in question form) with which part of the material they still have difficulty. For the teacher, this not only provides insight into the extent to which the students understand/master the material, but also a good starting point for the next lesson.