Every farmer in Kenya knows that seeds do not always sprout. Some rot in the ground, others dry out, and some fail completely. This experiment helps you understand exactly what conditions seeds need to germinate successfully. By comparing light vs dark, water vs no water, and warm vs cold, you will discover the optimal conditions for growing beans, maize, or any crop.
All materials are free or recycled:
- Bean seeds (20-24 seeds) - use dried beans from the kitchen (common beans, green grams, or cowpeas). Avoid canned beans - they will not germinate.
- 4 clear plastic cups or small containers - recycled yoghurt cups, water bottles cut in half, or small planting pots.
- Cotton wool or soft tissue paper - about 20-30 pieces. Alternatively, use soft cloth or paper towels.
- Water - clean tap water or rainwater.
- Marker pen or sticky labels - to label each container.
- Ruler (centimetres) - to measure root and shoot length.
- Notebook and pen - for daily observations.
- Cardboard box (for dark condition) - a shoebox works perfectly.
- Camera (optional but recommended) - to photograph progress for SBA evidence.
Total cost: 0 KES (dried beans are available in any kitchen; containers and cotton are recycled).
Light: On windowsill or well-lit area
Water: 1 tablespoon daily (keep cotton moist)
Temperature: Room temperature (22-28°C)
Light: On windowsill (same as Control)
Water: NO water at all - keep cotton dry
Temperature: Room temperature
Light: Inside cardboard box (complete darkness)
Water: 1 tablespoon daily
Temperature: Room temperature
Light: Minimal (inside refrigerator)
Water: 1 tablespoon daily
Temperature: Cold (4-8°C - inside refrigerator)
Prepare the four containers
Label each container clearly: A (Control/Light+Water), B (Light+No Water), C (Dark/Box), D (Cold/Fridge). Line the bottom of each container with 2-3 layers of cotton wool or tissue paper. The cotton should cover the entire bottom.
Place seeds in each container
Arrange 5-6 bean seeds on top of the cotton wool in each container. Space them evenly so they are not touching each other. Press each seed gently so it makes contact with the moist (or dry) cotton. For Condition C (Dark), prepare a cardboard box that completely covers the container.
Add initial water
Add 1 tablespoon of water to Condition A (Control), Condition C (Dark), and Condition D (Cold). Do NOT add any water to Condition B (Light+No Water). The cotton should be moist but not soaking wet. If there is standing water at the bottom, pour it out.
Place containers in their conditions
Place Condition A and Condition B on a windowsill or well-lit area (same light source). Place Condition C inside a cardboard box and close the box (complete darkness). Place Condition D inside a refrigerator (not freezer). For the refrigerator, place it in a corner where it will not be disturbed.
Daily care and observation (Days 1-10)
Every day at the same time (e.g., 8:00 AM or 5:00 PM):
- Add 1 tablespoon of water to Conditions A, C, and D (keep cotton moist). Condition B receives NO water.
- Count how many seeds have germinated (root or shoot visible).
- Measure the longest root and longest shoot (in cm) for each condition.
- Record observations in your log table (colour, mould, smell, changes).
- Take photos on Days 1, 3, 5, 7, and 10 for SBA evidence.
Copy this table into your notebook. Record observations every day at the same time. Use a separate page for drawings of the seeds at Day 1, Day 5, and Day 10.
| Day | Condition A Light+Water | Condition B Light+No Water | Condition C Dark+Water | Condition D Cold+Water |
|---|---|---|---|---|
| 1 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 2 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 3 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 4 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 5 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 6 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 7 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 8 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 9 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| 10 | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm | _____ seeds / roots ___ cm |
| Criteria | Exceeds (5) | Meets (4) | Approaching (3) | Below (2-1) |
|---|---|---|---|---|
| Experimental Setup & Variables | All 4 conditions set up correctly. Variables identified (light, water, temperature). Control identified. 5-6 seeds per condition. Daily care consistent. | 3-4 conditions correct. Variables mostly identified. 4+ seeds per condition. | Only 2-3 conditions. Missing identification of variables. Fewer than 4 seeds. | Setup incorrect or incomplete. No clear variables. |
| Daily Observations & Data Collection | 10 complete days of observations. Germination count AND length measurements recorded daily. Drawings or photos included. Consistent timing. | 8-9 days of observations. Most measurements recorded. | 5-7 days of observations. Missing measurements. | Fewer than 5 days. No measurements. |
| Analysis & Conclusion | Calculates germination percentage for each condition. Compares results. Explains WHY each condition affected germination (science of water, light, temperature). Identifies optimal condition for bean seeds. | Basic comparison of which condition worked best. Partial explanation. | States results without explanation. No germination percentage calculation. | No analysis or incorrect conclusions. |
| Documentation & Presentation | Complete log with photos on Day 1, 3, 5, 7, 10. Labelled diagram of a germinated bean seed. Written conclusion. Teacher/parent signature. | Photos on 3 days. Diagram present. Basic conclusion. | 1-2 photos only. Missing diagram or conclusion. | No photos or documentation. |
- Calculate germination percentage: (number of germinated seeds ÷ total seeds planted) × 100 for each condition.
- Create a bar graph comparing root length across the four conditions on Day 10.
- Write a hypothesis before starting: "I predict that Condition _____ will show the best germination because..."
- Extend experiment by transplanting one germinated seedling from Condition A into soil and observe growth for another 10 days.
- Research and explain: Why do some seeds need darkness to germinate? (Hint: Think about seeds that fall to the forest floor.)
- Condition A (Light+Water): Seeds should germinate within 4-6 days. Good root and shoot growth. Healthy green shoots by Day 7-10.
- Condition B (Light+No Water): No germination. Seeds may remain dry and hard, or may begin to rot. This shows that water is essential.
- Condition C (Dark+Water): Seeds germinate but shoots are pale yellow/white (etiolated - lacking chlorophyll). Shoots are longer but weaker than Condition A.
- Condition D (Cold+Water): Very slow or no germination. Cold temperatures slow down enzyme activity. Some seeds may rot before germinating.
Where Seed Science Leads
Understanding seed germination is the foundation of agriculture. Seed technologists test seed quality at companies like Kenya Seed Company. Agronomists advise farmers on planting conditions. Plant breeders develop new varieties that germinate faster or tolerate drought. In Kenya, the seed industry employs thousands of people - from lab technicians to field officers. This simple experiment is your first step into agricultural science.
Print or Save as PDF
Take this experiment guide to your lab. Print the observation log and rubric for daily recording.