The Effect of Different Types of Soil on the Growth Rate of a Plant

Plant’s growth varied from one place to another. It is affected by many factors, for example, the availability of abiotic factors like sunlight, atmosphere, temperature, climate, and soil. I’m wondering which type of soil is helpful to speed up plant’s growth, humus, sand, or humus and sand together?

If we grow a plant in humus and sand together, the rate of the plant’s growth will increase more, because humus will supply enough amount of nutrients since it is made of organic material. On the other hand, sand is important, since it supplies the plant with minerals and it has large particles that helps plants roots to be exposed to air.

Independent variable: Types of soil.

Dependent variable: Rate of growth.

Control variables: Sunlight, water, and temperature.

I will use three types of soil and one type of plants to be able to compare between the three types effect on plant’s growth.

Researchers have done many experiments on the effect of soil types on plant’s growth. One of the results states that loam (a mixture clay, sand, and silt) is the best for plant’s growth. Researchers show that each type of soil has its own characteristics in terms of having enough nutrients and the ability of water retention.

Humus soil, sand, humus and sand together, three plastic plates, lentils, ruler, cup, and water.

Step 1: Put 1.5 cup of sand in a plate.

Step 2: Add 20 seeds of lentil to it.

Step 3: Putting it in a place where there is enough sunlight.

Step 4: Add 0.5 cup water every 2 days.

Step 5: Collect observations every 2 days and start getting measurements for the length.

Step 6: Do 1, 2, 3, 4, 5 with humus and humus and sand together.

Day 2: Humus (cm): 0.3, Sand: 0, Humus and Sand: 0.1

Day 4: Humus (cm): 3.4, Sand: 0.1, Humus and Sand: 2.8

Day 6: Humus (cm): 6.2, Sand: 0.2, Humus and Sand: 5.9

Day 8: Humus (cm): 9.5, Sand: 0.4, Humus and Sand: 8.7

Day 10: Humus (cm): 12.8, Sand: 0.4, Humus and Sand: 10

Based on the data that I have collected by direct observations, I have found that lentils can grow in different soil types with different growth rates. As it is shown in the table, lentils has the highest potential growth in humus than sand or humus and sand. For example, after 10 days, the lentils height in humus is 12.8 cm, in sand is 0.4 cm, and in humus and sand is 10 cm. That means humus is the best type soil to be used for agriculture, since it includes all the nutrients components. I thought mixing sand with humus will give a chance for lentils to grow more, but that didn’t happen, because adding sand helps the roots to be more exposed to air, but it reduced the availability of nutrients that plants need. The results showed that no growth for lentils in sand, which means that sand is poor medium that does not support lentils’ growth. Based on that, I conclude that Saudi Arabia does not support such type of agriculture.

I have found that my hypothesis wasn’t right, since the results of this experiment showed that plants can grow better in humus soil more than humus and sand together or sand only. I think humus contains all nutrients required for plant’s growth, in addition to that, it keeps the roots safe, healthy, and exposed enough to air, so it will not be rotted.

I have concluded from this project that humus is the best medium to be used for agriculture. On the other hand, I have found that sand does not fit such type of plants. I conclude it is hard to grow lentils in KSA since it is a desert country. I hope that other researchers answer questions related like which plants can grow in more salty environment?

This research is very helpful for people in the Ministry of Agriculture. They can use such results to check which places of Saudi Arabia is qualified to have such product. Lentils grow very well in humus, so people in the Ministry of Agriculture will start working on production of humus by using cheap simple processes to be used as natural fertilizers. I have learned from this research many skills. Thinking skills were used a lot in analyzing, comparing, and contrasting data. In addition to that, I have developed research skills from the point of selecting the idea, the scientific background, the hypothesis, the procedure, the data collection, the data analysis, and drawing conclusions. I have learned to be patient by having data collection everyday and taking care of plants everyday.