MY hypothsis is that the sand and potting mix mixed together will help the spider plant grow the talles becaues they are to types of soil with good nutrients

An ideal soil would be made up of 45% minerals (sand, clay, silt), 5 % organic (plant and animal) material, 25% air and 25% water. The mineral portion would be loam (20 – 30% clay, 30 – 50% silt and 30 – 50% sand). It would be crumbly, relatively dark in color, smell earthy and rich, team with microorganisms and earthworms, have plenty of nutrients and a pH between 6.5 and 7

There are twelve orders (types) of soil, each with unique characteristics, like color, texture, structure, and mineral content. The depth of the soil also varies. The kind of soil in an area helps determine what type of plants can grow. https://ucanr.edu/sites/MarinMG/files/116762.pdf

Vocabulary (with definitions)

• Soil – a complex mixture of rock fragments, organic material, air and water
• Nutrients – substances essential for growth. Nitrogen, phosphorus, and potassium are key nutrients.
• Fertile – capable of producing abundant crops or vegetation 
• Sand - The largest soil particle size
• Seeding mix - an intentionally produced, randomly mixed set of two or more kinds of crop seed. 
• Potting mix- a blend of materials like sphagnum moss, bark, perlite, vermiculite, compost or coir that's intended for growing plants 

 https://www.iowaaliteracy.org

Soil supports plant growth by providing:

1. Anchorage: root systems extend outward and/or downward through soil, thereby stabilizing plants.
2. Oxygen: the spaces among soil particles contain air that provides oxygen, which living cells (including root cells) use to break down sugars and release the energy needed to live and grow.
3. Water: the spaces among soil particles also contain water, which moves upward through plants. This water cools plants as it evaporates off the leaves and other tissues; carries essential nutrients into plants; helps maintain cell size so that plants don’t wilt; and serves as a raw material for photosynthesis, the process by which plants capture light energy and store it in sugars for later use.
4. Temperature modification: soil insulates roots from drastic fluctuations in temperature. This is especially important during excessively hot or cold times of year.
5. Nutrients: soil supplies nutrients, and also holds the nutrients that we add in the form of fertilizer.

Three elements, carbon, oxygen and hydrogen, are essential to plant growth and are supplied by air and water. The other essential elements are referred to as plant nutrients, and are provided by the soil, or are added as fertilizers, and enter plants almost exclusively through the roots. These plant nutrients are divided into two groups. Those required by plants in large amounts are called macronutrients; these are nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. Plant micronutrients, needed in tiny amounts include iron, chlorine, zinc, molybdenum, boron, manganese, copper, sodium and cobalt. Macronutrients and micronutrients are all critical to normal plant growth and development; they are simply needed in different amounts.

Texture: Soil is composed of both minerals (derived from the rock under the soil or transported through wind or water) and organic matter (from decomposing plants and animals). The mineral portion of soil is identified by its texture. Texture refers to the relative amounts of sand, silt and clay in the soil. These three terms refer only to particle size, not to the type of mineral that comprises them. Sand is familiar to most of us, and is the largest textural soil size. Sand grains can be seen with the naked eye or with a hand lens. Sand provides excellent aeration and drainage.     

Structure: Sand is often found as individual particles in a soil, but silt and clay are almost always clumped into larger units called aggregates. The manner of this aggregation defines a soil’s structure. Soil structure is described by terms such as blocky, platy, prismatic and angular. Productive topsoils often have a granular soil structure. The size and shape of aggregates is influenced by mineral type, particle size, wetting and drying, freeze/thaw cycles, and root and animal activity. Decomposed organic matter, plant sugars excreted from roots, waste products of soil microbes, and added soil conditioners all act to cement particles into aggregates.   https://extension.umaine.edu 

 Controlled variables: I am going to give them the same amount of water, seeds,and keep the same amount of soil as well,

 Manipulated variables: I am going to use different  soils for each pot .

Responding variables: The length of the plant.

I am going to get all the soils I need and then set up in  the 4 pots I have. I will put in the pots the green beans sprouts, and spider plants. Each day, except for the weekend, I will water them with the same amount of water, and give them the same amount of sunlight and care. Everyday I will measure them and write down my data until they fully grow and  know which  type of soil helped the plants grow the tallest. 

i have noticed that the seeding mix helped the best

My conclusion is that my hypothesis was wrong. because my hypothesis was that the sand+potting mix would help the most, but the seeding mix helped the spider plant grow most and the green  beans only grew in the seeding mix but in the other soils it didn't grow

i will do this again but with different  soils aganised seeding mix

i might have measured a different  leaf each time

https://ucanr.edu/sites/MarinMG/files/116762.pdf 

https://www.iowaaliteracy.org

https://extension.umaine.edu 

i want to thank Mrs.Lovell,my friends,my teacher ms. klaver,my sibilings, and my parents for helping me