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    Glossary

    ReferencePlatform3 min read

    The terms every LetsGrow product shares, one or two sentences each. Terms that belong to one product are explained on the pages of that product.

    Terms

    Section titled “Terms”

    How your data is organised

    Section titled “How your data is organised”
    Term Meaning
    Module One data source of your account, such as a climate module, a weather station or a crop registration module. It has a number, a name, a template, a start date and sometimes an end date. See Modules, templates and item codes.
    Template The kind of data a module collects. Examples are Climate Extended, Weather Station, Water and Target Values.
    Item One measurement in a module. It has an item code, a description, an explanation and a value type.
    Item code The short code of a measurement. GHTEMP is the greenhouse temperature, DRNPCT the drain percentage.
    Crop What you select before Growi reads data. A crop has a start date, an end date when one is set, and a set of linked modules. See Choosing a crop.
    Crop group The group a crop is listed under. A group can also hold crops of other members. See Which data Growi can access.
    Finished crop A crop whose end date is in the past. A crop without an end date also counts as finished. You can still select it and ask about it.

    Value types

    Section titled “Value types”

    An item exists up to four times in a module, once per value type. The LetsGrow platform computes the day, night and 24-hour values, one value per day.

    Term Meaning
    5-minute value The measurement at 5-minute intervals.
    Day value One value per day for the period from sunrise to sunset.
    Night value One value per day for the period from sunset to sunrise.
    24-hour value (daily value) One value per day for the period from sunrise to the next sunrise, not midnight to midnight. It is written after that next sunrise, so until then the last day has no 24-hour value yet.
    Summary rule How an item is summarised over a period: average, sum, maximum, minimum or the value at midnight. A day, night or 24-hour value follows the rule of its item, so it is not always an average.
    Hourly value LetsGrow has no hourly value type. Growi makes hourly values itself from the 5-minute values. See Asking about your data.

    Measurements

    Section titled “Measurements”
    Term Meaning
    RH, RV Relative humidity. Growi writes RH in English and RV in Dutch.
    VPD plant The vapour pressure difference between leaf and air, calculated from leaf temperature. “VPD” on its own means VPD plant.
    VPD greenhouse The vapour pressure deficit of the greenhouse air, calculated from air temperature.
    RTR The ratio of temperature to radiation. It has daily values only, no 5-minute values.
    PAR sum The total PAR over a period. Growi can split it into the part from the sun and the part from lighting when the crop has those measurements.
    Radiation sum The radiation total of a whole day, in J/cm². Current radiation is in W/m². 1 MJ/m² is 100 J/cm².
    Climate monitor Measurements of the overall climate balance and of temperature, humidity and CO2.
    Crop registration Measurements of the crop itself, such as head thickness, fruit weight, trusses and plant load. There are registration templates for tomato, cucumber, pepper and other crops. Weekly registrations have daily values only.
    NovaCropControl Samples taken at one moment, with a sample date: nutrients in young and old leaf, and EC, pH and nutrients in drip and drain water. They are not continuous readings.
    Section titled “Related documentation”