All Science Fair Projects

Over 1000 FREE Science Fair Project Ideas!

Topics  > Biology > Botany

Plant density and rate of growthFeatured science projectScience project video


This experiment was conducted to find out how planting more plants in the same pot will affect their rate of growth. The experiment was done using garlic chives.


As the population of plants in soil increases, the rate growth of the plants will be reduced.

Scientific Terms

Germinate, sprout, photosynthesis, nutrients, carbon dioxide


Plant density

Seeds need soil, heat, oxygen and water to germinate. Initially the food required for the seed to germinate is stored in the seed. As the seed starts to germinate, the roots will start to grow towards the soil and the sprout will grow upwards. As the first tiny leaves appear,  photosynthesis is started.

In the next stage of growth the plant starts to compete for water and nutrients in the soil and also for sunlight and carbon dioxide above. Seeds that are planted too close to one another are known to grow taller initially to compete for sunlight. However this growth will not last long because as they grow bigger, the plants will have to compete for other resources in the soil like space for roots, water and nutrients.

In most cases, a high plant density will cause the plants to experience malnutrition, have stunted growth and  eventually die. This is why in plantations the spacing between plants and plant density is always controlled to produce better yields.

See our all-time most popular science projects
Search science fair projects Browse science fair projects
popular science fair projects
Complexity level:
Project cost ($):
Time required:
1 hour to prepare, 10 days for observation
Material availability:
Easily found
Safety concerns: