Results 1 to 4 of 4

Thread: Crop Growth Requirements (tables)

  1. #1

    Join Date
    Apr 2011
    Been Thanked: 10,879 Times

    Default Crop Growth Requirements (tables)

    Plant Growth requirements

    I originally posted these tables as a reply in a different thread but thought they might be worth a topic of their own with the accompanying explanatory text.

    The text is OCR'd so may contain errors.


    Crop Growth Requirements

    The following table of growth requirements is for plant species commonly grown in enclosed environments and provides suggested conditions to simulate average growth in field environments and commercial facilities.

    These are general suggestions that will provide good growth; it should be recognized, however, that conditions may differ for specific cultivars and may differ in particular commercial production facilities to fulfill specific quality or other requirements.



    Plants usually will be grown in a soilless potting medium or liquid culture. Several commercially available mixtures provide suitable media for plant growth, as discussed in the previous chapters. When plants are grown in a soilless media or liquid culture, use of a complete nutrient solution (approximating half strength Hoagland) is recommended, with the nitrogen concentrations modified as indicated in the table. Nitrogen is emphasized because this is the principal nutrient that is altered for a particular species or at particular stages of growth.

    If a soil-containing medium is used, it is recommended that the plants be fertilized with a commercial water-soluble fertilizer such as 20-10-20. When nitrogen concentrations are modified with a commercial fertilizer, P and K concentrations will also be modified.

    Recommendations for pH assume that a range of 5.5 to 6.5 is acceptable for most plants, and a pH of 4.5 to 5.5 is acceptable for crops requiring low pH.


    The recommended photosynthetic photon flux (PPFD) is for the top of the canopy. When light is indicated to be 12-20 hours, there is no specific day-length requirement for this species. The use of the longer period will provide a greater amount of total lighting, and thus an intensity toward the lower end of the recommended PPF range can be utilized to achieve good growth. If a short photoperiod is recommended, it is necessary to provide an intensity toward the high side of the recommended PPF range. No recommendations are provided on light source because chamber configuration, plant species, and desired response can all affect lamp selection.

    Special light requirements for specific species are noted in the comments column of the table.


    Recommendations are for air temperature at canopy height. The temperature for most plants can be set 2°C above or below the indicated temperatures and still produce normal plants, although growth rates will be altered. A light/dark fluctuation is recommended, and is required when shown in bold letters; most plants, however, will develop normally with a constant temperature that is an average of the indicated light and dark temperatures. The temperature period required to break bud dormancy of woody species is cultivar dependent; thus, a range of time is indicated.


    Control between 60% and 70% relative humidity is recommended for most crops and can be achieved readily in most controlled environment chambers. Exceptions are noted in the comments column.


    The environmental conditions required for successful plant growth in controlled environments are often not the same throughout all stages of plant growth. For that reason, the table has been divided into four, somewhat arbitrary, stages of development: Propagation, Vegetative, Flower Initiation/Development, and Fruit/Seed Development. These categories may not be technically correct for all the plants described, but they should provide functional guidelines for maintaining a desired growth rate for the listed species.

    Propagation is considered the period from planting to emergence of the first true leaf. Environmental conditions for acclimation of tissue-culture transplants, seedlings, and rooting of cuttings are also included in this section when they are considered to be routine propagation methods.

    Vegetative is the period when reproductive structures are not actively developing on the plant. This typically includes the period of rapid stem elongation and leaf expansion that precedes flower formation. For woody species, this period may include the period of stem and leaf growth that occurs when flower buds are present but dormant.

    Flower initiation/development is the period from the initiation of flowers through shedding of pollen (anthesis), flower formation, pollination, and fertilization. However, for many perennial woody plants, initiation of flower buds occurs at a time separate from flower development. The recommended environment for breaking dormancy of the initiated flower buds of these woody species is indicated in the comments column at the right margin.

    Fruit/seed development is the period following fertilization to maturity of the seed.

    Source: Plant Growth Chamber Handbook, NC101 regional committee on Controlled Environment Technology and Use.

  2. The Following 8 Users Say Thank You to Anonymiss For This Useful Post:

    Cats (17-05-21), erbie (24-11-13), Goodbuddy (03-01-12), Grampysid (06-07-13), Grub (03-01-12), Murdock (03-01-12), sludged72 (11-07-13)

  3. #2
    Tiles Of The Simpsons Champion!
    Join Date
    Sep 2008
    Been Thanked: 23,393 Times


    Good, informative post there Missy.



  4. #3

    Join Date
    May 2012
    Been Thanked: 6 Times


    Ton of info .. thanks for the time u spent to make our life easier

  5. #4

    Join Date
    Sep 2013
    Been Thanked: 0 Times


    Thanks, this is a great post.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  • Disclaimer - You must be over 18 years old to view/use this site does not encourage growing Cannabis or possessing Cannabis. Learning how to grow Cannabis instructions should be for educational purposes only. All Information contained in this web site is for: Historical reference, Scientific reference and Educational purposes only. Visitors to this website are advised against breaking the law as It is illegal to smoke, grow, or possess cannabis in the UK and some US States