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Needs of Plants for Germination
and Growth
Spring
Early February
Edible Schoolyard Pittsburgh
Materials
Preparation

Wide-mouth mason jars (1 per group)


Potting soil, small baskets

Different types of bean seed
Arrange desks into small clusters and line with
newspaper. Moisten potting soil and divide it
into smaller baskets. Place baskets in the middle
of each group of desks.

Black construction paper, tape, and markers


Spray bottle
Split a few bean seeds in half and place in a small
containers. Set containers aside for Part 1.

Newspaper

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Garden journals and pencils
If working with multiple bean seed varieties,
place seeds in tiny envelopes and label them
PROCEDURE
Part 1: Prepare Seed Sprouting Jars

“Divide students into small groups and arrange each group around a cluster of desks. “What do plants need to
grow?” As a class, generate a list of plant needs on the board. “Today were are going to learn about plant needs
for germination and growth.” Define germination.

Introduce bean seed. On the board, draw a diagram on the seed and label seed parts. “The seed coat is the
outermost layer of the seed. The inside of the seed contains and embryo and a food store.” Pass around the
split bean seeds for groups to examine. “Under the right conditions, the embryo will grow into a new plant.”
Explain seed needs for germination. Mention planting depth and temperature range.

Pass out mason jars to each group. Instruct students to fill the jars nearly to the to with potting soil. As they
work, remind students to gently shake the jars to settle the soil. When all groups have finished, explain planting
procedure. “Plant seeds directly against the glass of the mason jar. You will plant three seeds per container, all
at different depths.” Using a mason jar, demonstrate how to plant seeds at different depths.

Once students have planted seeds, instruct them to lightly pat down on the soil and water well. Then,
demonstrate how to wrap a piece of black construction paper around the jar. “First, label your construction
paper with a piece of tape. Include names of group members, date, and type of seed planted. Then, wrap paper
around the jar and secure with tape.”

“What changes do your predict will take place over the next week?” Make a list as a class. Place jars in a warm
location and water daily. Students should visit jars daily and record any developments in their garden journals.
Part 2: Examine Sprouted Seeds (1 week later)

Gather in groups. Take out mason jars and examine sprouted seeds. “How many seeds did you plant? How
many germinated successfully? For the seeds that did not sprout, what do you think the problem was?” Review
seed needs for germination. Explain the importance of maintaining proper planting depth. “Plants only have so
much energy contained in their food store.”

“What new plant parts have formed above ground?” Make a list as a class. Remove construction paper and
examine seeds on the inside of the glass. “What new plant parts have formed below ground?” Draw a diagram
on the board illustrating parts of a sprouted seed. “What do plants require in order to sustain growth over
time?” (sun, soil, water, and air). Reserve some seedlings for continued growth and observation.
Needs of Plants for Germination and Growth
Planning & Design
Objectives
ENGAGE
As a class, generate a list of human needs for survival.
From that list, identify the following: “What are the most
essential needs?” (food and water). “What are other
important needs?” (shelter, clothing, community, etc.) As
a class, rank needs in order of importance. “Plants and
humans have some basic needs in common. What basic
needs do plants share with humans?” Circle shared needs
on the list. “As you know, human beings start their lives on
a diet of milk, followed by liquid, then solid food. Similar
to humans, plants have different needs during different
stages of their lifecycle.” Transition to Part 1.

Students will be able to define germination

Students will be able to identify three parts of
a seed – seed coat, embryo, and food store

Students will understand seed needs for
germination and plant needs for growth

Students will be able to identify above- and
below-ground parts of a sprouted seedling
EXPLAIN
Seed Needs for Germination
A seed contains the beginnings of a new plant. In simple terms, seeds contain three main parts – the outer seed
coat, an embryo (or immature plant) and a large food store. Seeds remain in a stage of dormancy until presented
with the proper conditions for germination. In order for seeds to successfully germinate, they require water, oxygen,
and the appropriate temperature range. A seed’s optimal temperature range depends of the type of plant. Spinach
seeds can germinate under cooler conditions, while tomato seeds require warmer temperatures. Once
environmental conditions are favorable for germination, the protective seed coat begins to dissolve and the
embryonic root (also called the radicle) emerges from the seed. As this root grows downward in search of water and
soil nutrients, two aboveground plant parts emerge – the stem (hypocotyl) and seed leaves (cotyledons). Once a seed
exhausts its food store, it is considered an established seedling. From here on out, the plant is on its own.
Plant Needs for Growth
Once a plant is established in the soil, its needs change. In order to sustain growth over time, seedlings require
adequate access to sun, soil, water, and air. If any of those essential elements are missing, the plant will not survive.
Plants require sunlight in order to produce food through photosynthesis. Soil supplies the plant with water and
mineral nutrients for growth. Plants use water to transport nutrients between the root system and leaves. Plants
require carbon dioxide present in the air for photosynthesis. Other important factors also affect growth, such as
proper spacing and a plant’s preferred temperature range. Give plants what they need and they will give back!
PROCEDURE MODIFICATION
Part 1: Assign each group with a unique set of experimental variables. For
example, only some groups supply their seeds with water. Or, place some
seeds in hot environmental conditions (heat lamp) and others in cooler
ones (the fridge/freezer). Try germinating seeds in an environment devoid
of oxygen, such as a sealed mason jar. Part 2: Once seedlings germinate,
place them in different environmental conditions. What happens to the
plant when you take away sun, soil, water, or air? Discuss results.
Additional Materials

Access to different growing
environments (heat lamp,
fridge, freezer, etc).

Garden journals and pencils
EVALUATE
Journal prompt: What three things do seeds require in order to germinate? What four things do plants require in
order to grow? Are there any other environmental factors that are also important?