Greenhouse Management - Soil & Water Flashcards
What environmental factors affect growth?
Temperature, Water, Nutrition, Media, and Light
What percentage of water does a plant contain?
70-90%
Gravitational water
Water that Soil can’t hold against gravity
Capillary water
Water that is held against gravity
Optimal temperature for plants
86 degrees
The _______ of light affects photosynthesis
Intensity
Media
Clay, sponges, dirt, rocks, etc.
What soil is made up of
Sand, silt, clay, and organic matter
The three layers of soil
Topsoil, subsoil and bedrock
The layer of soil containing the most organic matter
Topsoil
This type of soil is desirable for most plants
Medium loam
This soil particle drains well but doesn’t hold water or nutrients
Sand
What is aggregation?
When soil particles cling together in large, crumb-like shapes
Pros of soil-less media
Mix is mostly uniform, sterile, lighter and easier to handle, good drainage
Cons of soil-less media
Easily blown over outside, micronutrients may be missing, issues when transplanting to soil
Perlite
Volcanic origin, improves drainage
Soil-less media with high water holding capacity
Sphagnum moss, peat moss and vermiculite
Macroelements
Nitrogen, phosphorous, potassium, carbon, hydrogen and oxygen
Secondary elements
Calcium, magnesium and sulfur
Microelements
Boron, copper, chlorine, iron, manganese and zinc
What pH range do plants prefer?
5.6-7.0
Ideal air to water ratio for plants
50:50
Cold temperatures slow the _______ process
Metabolic
