Expert: Darlene K. Kittle - 10/28/2009

Question
I am researching my philodendron after a science experiment. I re-potted my plant in gravel instead of potting soil, and it lived, but only barely. I would like to know what nutrients and/or minerals philodendrons use that the take out of the soil.

Answer
Hannah,

I am surprised that it did not do just fine. It actually gets as much from the sun and water and it can get most of the following nutrients from very gravelly soil. I suspect that your plant almost died due to being watered too much and that it had nothing to do with the gravel it was being grown in. If you did not allow the gravel to dry out between waterings your were watering it too often. Here are the nutrients plants take from the soil:

Macronutrients

Nitrogen (N)
Nitrogen is a part of all living cells and is a necessary part of all proteins, enzymes and metabolic processes involved in the synthesis and transfer of energy.
Nitrogen is a part of chlorophyll, the green pigment of the plant that is responsible for photosynthesis.  
Helps plants with rapid growth, increasing seed and fruit production and improving the quality of leaf and forage crops.  
Nitrogen often comes from fertilizer application and from the air (legumes get their N from the atmosphere, water or rainfall contributes very little nitrogen)

Phosphorus (P)
Like nitrogen, phosphorus (P) is an essential part of the process of photosynthesis.  
Involved in the formation of all oils, sugars, starches, etc.
Helps with the transformation of solar energy into chemical energy; proper plant maturation; withstanding stress.
Effects rapid growth.
Encourages blooming and root growth.
Phosphorus often comes from fertilizer, bone meal, and superphosphate.  

Potassium (K)
Potassium is absorbed by plants in larger amounts than any other mineral element except nitrogen and, in some cases, calcium.  
Helps in the building of protein, photosynthesis, fruit quality and reduction of diseases.
Potassium is supplied to plants by soil minerals, organic materials, and fertilizer.

Calcium (Ca)
Calcium, an essential part of plant cell wall structure, provides for normal transport and retention of other elements as well as strength in the plant. It is also thought to counteract the effect of alkali salts and organic acids within a plant.  
Sources of calcium are dolomitic lime, gypsum, and superphosphate.

Magnesium (Mg)
Magnesium is part of the chlorophyll in all green plants and essential for photosynthesis. It also helps activate many plant enzymes needed for growth.
Soil minerals, organic material, fertilizers, and dolomitic limestone are sources of magnesium for plants.

Sulfur (S)
Essential plant food for production of protein.
Promotes activity and development of enzymes and vitamins.
Helps in chlorophyll formation.
Improves root growth and seed production.
Helps with vigorous plant growth and resistance to cold.
Sulfur may be supplied to the soil from rainwater. It is also added in some fertilizers as an impurity, especially the lower grade fertilizers. The use of gypsum also increases soil sulfur levels.  


Micronutrients

Boron (B)
Helps in the use of nutrients and regulates other nutrients.  
Aids production of sugar and carbohydrates.  
Essential for seed and fruit development.  
Sources of boron are organic matter and borax

Copper (Cu)
Important for reproductive growth.
Aids in root metabolism and helps in the utilization of proteins.  

Chloride (Cl)
Aids plant metabolism.  
Chloride is found in the soil.  

Iron (Fe)  
Essential for formation of chlorophyll.
Sources of iron are the soil, iron sulfate, iron chelate.  

Manganese (Mn)  
Functions with enzyme systems involved in breakdown of carbohydrates, and nitrogen metabolism.  
Soil is a source of manganese.

Molybdenum (Mo)  
Helps in the use of nitrogen
Soil is a source of molybdenum.  

Zinc (Zn)  
Essential for the transformation of carbohydrates.
Regulates consumption of sugars.
Part of the enzyme systems which regulate plant growth.  
Sources of zinc are soil, zinc oxide, zinc sulfate, zinc chelate.

I am glad your plant survived.

Darlene