The Water Requirement to Prepare Soil calculator estimates the minimum and maximum water range for plant growth to apply to initially moisten soil so that plants will not suffer from over or under watering.
INSTRUCTIONS: Choose units and enter the following:
Water Requirement for Soil (Vw): The calculator returns the minimum and maximum amount of water in gallons. However, this can be automatically converted to compatible units via the pull-down window.
The maximum percentage of water typically required for most plants to survive is based on a rough estimate derived from a factor known as the field capacity.
The value for the field capacity (`sigma_"fc"`) is estimated between 0.1 `"vol water"/"vol soil"` and 0.35 `"vol water"/"vol soil"`. This equation uses the upper bound of this field capacity range. To be more conservative you will want to use less water than this equation estimates but this equation will give you a starting point for your estimates.1
The percentage of water typically required for most plants to survive is based on a rough estimate derived from a factor known as the permanent wilting point. the permanent wilting point, `sigma_"wp"`, is given as a range because different plants endure different levels of dry soil. We have used the upper bound of this range so that this equations computes the safe minimum of water for your specified volume of soil.
The value for the permanent wilting point (`sigma_"pwp"`) is estimated between 0.01 `"vol water"/"vol soil"` and 0.25 `"vol water"/"vol soil"`. This equation uses the upper bound of this permanent wilting point range. To be more conservative you will want to use more water than this equation estimates but this equation will give you a starting point for your estimates.
Potting Mix is combination of organic materials (e.g., peat moss, aged bark and pumice) but no soil (dirt) that is used in lieu of potting soil to improve drainage. Because potting mix has no soil, it tends to be lighter than potting soil and provides a more sterile medium for plants with fewer disease carrying agents. Potting mix is most commonly recommended for plants in containers, and potting mix is particularly desirable for starting seeds.
Garden Soil is a gardening product sold that contains natural soil (dirt) comprised of mixture of loam, clay and sand. Garden soil is often used in raised gardens or planters as a healthy and easy medium for plants and seeds on top of the natural soil in one's yard. Garden Soil differs from Potting Mix in that garden soil contains real soil (dirt), where Potting Mix does not.
Always use local pricing for the most accurate cost! However, vCalc conducts a periodic pricing survey from nationally advertised retailers for various materials. The current Garden Soil Price Survey sample information for Garden Soil and Potting Mix is as follows:
The Pricing Data can be used the the Raised Planter calculator. Note, this information is propagated into several pages in vCalc.