Author Archives: John Erwin

About John Erwin

John Erwin is a professor in the Department of Horticultural Science at the University of Minnesota. He can be reached at erwin001@umn.edu.

When To Light and When To Shade: Ready Research Results

Plants increase in mass, or dry weight, through photosynthesis. Photosynthesis is the process that harvests light energy to drive critical processes resulting in plant growth. Why is increasing photosynthesis important? Increased photosynthesis is associated with increased flowering, increased plant quality and increased post-harvest life. How much, or how fast, a plant can photosynthesize depends on

Energy-Efficient Annuals: Perfecting Temps & Light

Bedding and garden plants are the largest category of floriculture crops in the United States with a wholesale value of $1.76 billion in 2007. Scheduling these crops in flower for specific market dates, at different times of the year, can be a challenge. In addition, most bedding plants are produced when energy for heating a

Essential Equipment

If you think about it, there has been a huge increase in tools and instruments available to greenhouse growers during the last couple of decades that vary from large instruments like greenhouse control computers, to more portable instruments that help with day-to-day monitoring of plant growth. This article outlines some of the portable instruments available