Click on a topic in the menu to view specific articles (in pdf format) published in trade magazines. Articles posted with permission from Greenhouse Product News, Greenhouse Grower, Greenhouse ManagementGrowerTalks, and other horticulture magazines.

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  • The economic viability of LED lighting

    Published on October 7, 2016

    Determine whether LED lighting is right for your operation by considering seven important factors that impact return on investment.

  • Fascination on poinsettia

    Published on August 8, 2016

    Did you hit your poinsettias with too much growth retardant? This Michigan State University research shows how to recover using products that contain gibberellic acid.

  • Red light and plant growth

    Published on August 7, 2016

    Many LED fixtures developed for plant growth applications emit a large proportion of red light. Learn about the roles of red light in photosynthesis, extension growth, and flowering, as well as human perception.

  • Juvenility in perennials

    Published on June 29, 2016

    Plants started by seed have a juvenile phase and they must develop to a certain maturity before they attain the capacity to flower.

  • A closer look at far-red radiation

    Published on May 7, 2016

    Far-red light can be defined as photons with wavelengths from 700 to 800 nanometers. It can promote extension growth and flowering, and at least indirectly increase growth.

  • Diffused glass

    Published on April 23, 2016

    Growers need to weigh the advantages of diffused glass with its cost considering their greenhouse location, production periods, and types of crops grown.

  • Efficacy of lamp types at controlling flowering

    Published on February 23, 2016

    This article summarizes the effectiveness of low-intensity lighting from different lamp types at regulating flowering of a wide range of ornamental crops based primarily on research performed at Michigan State University.

  • Improve rooting of cuttings

    Published on January 19, 2016

    Successful rooting of cuttings requires careful management of the environment, especially air and media temperature, humidity and light.

  • Environment and PGR interactions

    Published on December 17, 2015

    When plant growth regulators (PGRs) are applied as sprays, their efficacy can be greatly influenced by the environment. Understanding how environmental factors influence PGR spray efficacy can lead to more effective and predictable plant responses.

  • Keys to successful seedling production

    Published on November 19, 2015

    Although the topics discussed don’t include all of the key aspects of plug production, focusing on these key parameters will certainly help lead to success.

  • Lighting metrics... and what matters

    Published on October 23, 2015

    This article discusses some of the metrics used to describe or quantify the light emitted from various fixtures (or LED arrays), some of which are highly relevant to plant applications and others that are only applicable to people.

  • Photoperiodic vs. photosynthetic lighting

    Published on September 23, 2015

    There is sometimes confusion about photoperiodic lighting (to regulate flowering) and photosynthetic lighting (to increase plant growth) in greenhouses. This article differentiates these two lighting applications.

  • Boom lighting

    Published on July 23, 2015

    We have developed some general guidelines based on limited research with simulated boom lighting, studies with cyclic lighting, and grower experiences.

  • Interactions of light, CO2, and temperature on photosynthesis

    Published on June 23, 2015

    Often times, we simplistically think about light as the driver of photosynthesis, and temperature as the key to control crop timing. Although that’s generally true, other cultural and environmental factors influence crop growth and quality.

  • Crops with relatively low optimum temperatures

    Published on May 17, 2015

    At temperatures above the optimum, plants experience stress and the rate of development begins to decrease. Learn which crops grow best at relatively cool temperatures.

  • Trending: PGR sprenches

    Published on April 17, 2015

    A sprench of a plant growth regulator (PGR) is a hybrid of a spray and a drench application, and is increasingly being used in the production of greenhouse ornamentals.

  • Light wavebands & their effects on plants

    Published on March 23, 2015

    This article discusses how the four primary wavebands of light (blue, green, red, and far red) influence plant growth and development. Light wavebands also interact with each other, but only a few are mentioned here.

  • The PGR ancymidol

    Published on February 17, 2015

    Plant growth retardants (PGRs) that contain the active ingredient ancymidol aren’t as commonly used in floriculture as most other PGRs, but there are some potential upsides that merit consideration.

  • Dealing with the cold

    Published on January 17, 2015

    It’s naturally tempting to reduce the greenhouse temperature so that less energy is consumed per day, but there are consequences to such actions that growers should understand.

  • Managing temperature during propagation

    Published on December 19, 2014

    Temperature primarily drives the rate of root and shoot development while light provides the energy to promote that growth. When one of these environmental factors is not optimized, rooting is delayed.

  • Replacing incandescents with LEDs

    Published on November 23, 2014

    LED lamps developed to regulate flowering are considerably more expensive than incandescent or compact fluorescent bulbs, but they last much longer, consume less energy, and are at least effective.

  • Increasing plant height

    Published on October 17, 2014

    There are numerous ways to promote extension growth, including changes to plant culture or the growing environment, or applying a plant growth regulator that includes gibberellic acid.

  • The double-ended HPS lamp

    Published on September 23, 2014

    Double-ended high-pressure sodium lamps are considerably more efficient at converting electricity into light useful for photosynthesis than single-ended lamps.

  • Effective use of PGRs

    Published on July 18, 2014

    Plant growth regulators (PGRs) are sometimes not used to their potential; they are sometimes applied too late or at an inappropriate rate. Here are some important considerations for getting the most out of your PGRs.

  • LEDs vs. HPS lamps: A reality check

    Published on June 23, 2014

    With all of the promise and potential of LEDs, some myths and misconceptions are being perpetuated - hence the need for a reality check.

  • Dealing with high temperatures

    Published on May 17, 2014

    Some of the most common heat-stress symptoms on ornamentals include lower-leaf yellowing, thin and elongated growth, delayed flowering, and small flowers.

  • Using chlormequat chloride with success

    Published on April 18, 2014

    Chlormequat chloride is a plant growth retardant used to promote flowering or inhibit extension growth of floriculture crops grown in greenhouses, shadehouses and container nurseries.

  • Control flowering with LEDs

    Published on March 23, 2014

    Is it worth paying extra for LEDs? Researchers at Michigan State University found that the long-term benefits may outweigh the up-front costs.

  • Growing seedlings under LEDs, part 2

    Published on February 23, 2014

    In the second part of a two-part series, Michigan State University researchers share their findings in germinating seedlings indoors under LED lights.

  • Cold-intermediate bedding plants

    Published on February 22, 2014

    Bedding plants that stop developing at moderately low temperatures can be labeled as cold-intermediate plants. This categorization is based on estimates of base temperatures derived from research data primarily generated at Michigan State University.

  • Growing seedlings under LEDs, part 1

    Published on January 23, 2014

    In the first part of a two-part series, Michigan State University researchers share their findings in germinating seedlings indoors under LED lights.

  • Cold-tolerant bedding plants

    Published on January 22, 2014

    Bedding plants that stop developing at low temperatures can be labeled as cold-tolerant plants. This categorization is based on estimates of base temperatures derived from research data primarily generated at Michigan State University.

  • Cold-sensitive bedding plants

    Published on December 22, 2013

    Bedding plants that stop developing at a relatively high temperature can be labeled as cold-sensitive plants. This categorization is based on estimates of base temperatures derived from research data primarily generated at Michigan State University.

  • Flowering of petunia at low temperatures

    Published on November 22, 2013

    Temperature and photoperiod interact to influence flowering of petunia. This article presents research-based information to better understand how to manipulate the environment for rapid flowering.

  • Keeping it Green

    Published on November 18, 2013

    Applications of plant growth regulators such as benzyladenine (BA; a cycokinin) and/or gibberellic acid (GA) may suppress lower-leaf yellowing and senescence.

  • Turning on/off supplemental lighting

    Published on October 23, 2013

    The costs to operate high-intensity lighting in greenhouses are quite high, so operation of lights should be managed as efficiently as possible.

  • Problems with footcandles, lux and lumens

    Published on September 23, 2013

    The horticultural industry should discontinue use of photometric units such as lumens, lux and foot-candles. These units are based on people’s perception of light and are a highly misleading indicator of plant growth and flowering applications.

  • Successful use of the PGR daminozide

    Published on August 18, 2013

    The plant growth regulator (PGR) daminozide is used as a foliar spray primarily to inhibit extension growth of ornamental crops.

  • Temperature on chyrsanthemum

    Published on July 17, 2013

    Once flower buds are visible, adjusting the growing temperature has little or no impact on time to flower unless plants are held at low temperatures (50° F or less).

  • Using the PGRs Collate and Florel

    Published on June 18, 2013

    Achieving consistent results with the plant growth regulators (PGRs) Collate or Florel can be trickier than with other PGRs simply because the active ingredient, ethylene, is a gas.

  • PGR application considerations

    Published on May 18, 2013

    This article briefly presents some of the considerations when selecting which plant growth regulator (PGR) rate, method and active ingredient to apply to greenhouse-grown ornamental crops.

  • Non-chemical height control techniques

    Published on May 18, 2013

    There are several environmental and cultural practices that can produce shorter plants, but strategies must be implemented over a period of time to achieve desired outcomes.

  • Ethephon drenches on bedding plants

    Published on April 18, 2013

    In the second of a two-part series with ethephon (e.g., Florel), we shows that drenches are a viable method to control height and size of several bedding plant crops.

  • PGR dilution guide

    Published on April 18, 2013

    A critical factor for effective use of plant growth regulators (PGRs) is that the solution is mixed in the appropriate concentration.

  • Farm Information Resource Management (FIRM)

    Published on March 27, 2013

    Improve your life and achieve your goals through an educational process that applies management, production and economic knowledge to critical issues, needs, and opportunities.

  • Managing photoperiod in the greenhouse

    Published on March 23, 2013

    This six-page bulletin provides information on how to control the day length in commercial greenhouse production of floriculture and nursery crops.

  • Wave petunia smart scheduling

    Published on March 22, 2013

    We quantified the effects of temperature and photosynthetic daily light integral on flowering time and characteristics of 15 Wave petunia cultivars, then generated temperature-based flowering time models for more predictable greenhouse scheduling.

  • Plug / liner dip guidelines

    Published on February 18, 2013

    A plug or liner dip is a plant growth retardant (PGR) application technique for ornamentals in which a tray of finished young plants is placed into a shallow PGR solution for a short period of time.

  • Controlling flowering of Echinacea

    Published on February 8, 2013

    Research-based information is presented about how to control the flowering of purple coneflower (Echinacea) for commercial production.

  • Lighting plugs at different growth stages

    Published on January 23, 2013

    Plants that received supplemental lighting during the entire plug stage were of highest quality. The greatest benefits occurred when seedlings were lighted during the later stages.