Aeroponic Plant Food
Colorado State University’s Master Gardener Program
Whiting, D., Card, A. and Wilson, C. from Colorado State University’s Master Gardener Program say that plants need 17 elements for normal growth (CSU, 2009). The scientists make a distinction between plant nutrition usually found in soil, and fertilization used to supplement nutrient deficiency.
Aeroponic Plant Food Using an Aeroponic Growing System
This article explores plant food using an aeroponic growing system with organic vegetables in mind. An indoor aeroponic system uses less water and nutrients because the plant roots are sprayed in intervals using a precise drop size that can be utilized most efficiently by osmosis to nourish the plant. Little excess nutrient solution is lost to evaporation or runoff. Plant disease is minimized because the roots are left open to air, avoiding soaking in a stagnant moist medium.
Carbon, hydrogen, and oxygen
are present in air and water. Water may contain a variety of elements according to your local treatment plant additions and should be factored into your final conductivity factor, or cF (Khara, 2010). Primary nutrients are nitrogen, phosphorus, and potassium and are used by plants in different amounts according to the growth stage. Secondary nutrients are calcium, magnesium, and sulfur, and micro-nutrients are iron, zinc, molybdenum, manganese, boron, copper, cobalt, and chlorine. Complicating the formula more, roots use nutrients as ions in water; positively charged cations, or negatively charged anions. An example of a cation is ammonium, NH4+, and an anion nitrate, NO3- , both important nitrogen sources for plants. As plants use the ions, the pH of the solution can change, meaning it can lean too far positive or too far negative. The optimal pH for plant growth is between 5.8 and 6.3. In aeroponics systems where water and nutrients are recycled, it is important to measure the acid/base or pH measurement to allow plants to absorb nutrients. Aeroponic systems using spray to nourish the roots use much less liquid resulting in easier management of nutrient concentration with greater pH stability.
Watch Your Plants Grow
While many companies offer a wide variety of plant nutrient solutions, it is important to observe your plants growth and fine tune your individual program. The Virginia Cooperative Extension program from Virginia State University has published a table of symptoms that can result from nutrient deficiencies (Sorneson,R. 2009).
|Entire plant is light green in color; lower leaves are yellow; growth is stunted||Nitrogen|
|Entire plant is bluish-green, often developing a red or purplish cast; lower leaves may be yellow, drying to a greenish-brown to black color; growth may be stunted||Phosphorous|
|Leaves have a papery appearance; dead areas along the edges of the leaves; growth is stunted||Potassium|
|Lower leaves turn yellow along the tips and margin and between the veins; the lower leaves wilt||Magnesium|
|Young stems and new leaves die||Calcium|
|Leaf tissue between the veins is lighter in color; yellowed; papery in appearance||Zinc|
|Leaf tissue appears yellow, while the veins remain green||Iron|
|Leaf edges appear dark green or blue; leaf edges curl upward; young leaves permanently wilt||Copper|
|Young leaves turn pale green, while the older leaves remain green; plant is stunted and spindly||Sulfur|
|Growth is stunted; lower leaves have a checkered pattern of yellow and green||Manganese|
|Leaves are stunted, pale green, and malformed||Molybdenum|
|Young leaves are scorched at tips and margins||Boron|
Keep in mind that different plants have different nutrient requirements and in the initial vegetative stage require larger amounts of nitrogen than in the flowering cycle when phosphorus and potassium are required in greater amounts.
Human diets are complicated so it is no surprise that plant diets have variables to consider as well. Using a liquid aeroponic plant food spray with less waste helps keep the solution stable, and monitoring your plants for healthy growth is vital in arriving at optimal results. Heirloom vegetable seeds are recommended to give your plants the best possible start. Nothing replaces practice and experience in growing your own vegetables for your family’s healthy diet.
Sorenson, R., Relf, D., 2009. Home Hydroponics. Retrieved 14 November 2010 from http://pubs.ext.vt.edu/426/426-084/426-084.html
Whiting, D., Card, A., Wilson, C., and Reeder, J., 2009. Plant Nutrition. Retrieved 3 November 2010 from http://www.cmg.colostate.ed