Unit 3 Part (A). Experiment 4
Organic and Inorganic Nutrients
A plant is made up of basic building blocks from the earth's environment. Most plants are mostly made of water. When a plant is dried it loses as much as 90% of its weight in lost water. The 10% of the remaining dried plant are made up of 16 elements that plants require to survive and grow.
Of the 16 elements, 96% of that are carbon, hydrogen and oxygen, which are obtained from the air and water. The remaining 13 elements are usually obtained from nutrients in the water, and these are what must be supplied in a hydroponic nutrient. The nutrients needed only supply about 1.5% of the wet weight of the plant. Therefore, 1.5 pounds of nutrient should supply about 100 pounds of plant material. The more of the finished plant is edible, the more food you can produce with the nutrient. Corn is 50% edible, while lettuce is 90% edible.
There are two basic types of nutrients available for hydroponics:
Inorganic - The various compounds needed by plants are supplied by chemical processing or mined elements
Organic - the various compounds are supplied by a material from animal or plant origin. This is usually decomposed plant and animal litter.
To test both nutrients, make up two simple growers as described in experiment 1.
Label one grower organic and the other inorganic. Fill each grower with a growing media such as Perlite or small gravel. Plant two bean seeds in each grower, about 1" under media surface.
1. Locate two 1-gallon jugs to mix nutrient for the growers. Fill each container with water.
2. Put 1/8 spoon of root nutrient into one 1-gallon jug of water. To that add 1/8 teaspoon of calcium nitrate and 1/16 teaspoon of magnesium sulfate. Label this jug inorganic.
3. To make organic nutrient water, place 1/2 cup composted steer or chicken manure (readily available in garden shops) in a loosely woven cloth or old thin sock, tied to secure. Place nutrient sack in 1-gallon jug of water and leave for a day or overnight. This organic tea is ready when it is a strong brown tea color. Label this jug organic.
4. Place both growers with beans in a sunny area and allow seeds to germinate. Water daily with the appropriate nutrient water by gently pouring the water into the container while holding your finger over the drain stem. Fill until the water raises to the top of the growing media. Place the container under the drain stem to catch the nutrient water as you remove your finger, allowing the water to drain from the grower. Some nutrient water will remain in the grower, depending on where the stem is placed.
DATA RECORD SHEET
Compare growth rates of organic and inorganic nutrients.
Organic Nutrient Inorganic Nutrient
Growth 2 Weeks:(Height)
Growth 3 Weeks:
Growth 4 Weeks:
Revised: 1 May 2016