Poinsettia Focus on Growth

In this installment of my poinsettia blog, I will discuss growth characteristics. All of the poinsettias in this montage of images were planted within a couple days of each other. The difference I observe is the south end poinsettias (the hotter end of the greenhouse) are shorter and growing slower than the north end (the cooler part of the greenhouse).

The greenhouse is configured with a side vent and cool cell cooling system on the north wall of the greenhouse and the exhaust fans are on the south end of the greenhouse. To cool the greenhouse, the fans draw outside air from the north side of the greenhouse through the building and exhausts it on the south end. Cooling is enhanced with a wet sump cool cell system. Water is trickled over a cardboard type cell. Outside air moves across the wet cell. As cool moist air picks up greenhouse hot air, the south fans exhausts the hot air from the greenhouse. When outside air humidity is low we can lower the greenhouse temperature 10-15 degrees.

The problem is that the north end is normally cooler than the south end and that is why I am writing this blog edition. The heat has had a dramatic impact on the growth rate of the poinsettias. The first image shows the south end of the greenhouse. If you look close you can see in taller lusher green plants on the north end.

The outside air temperatures have been in the 90's for the past three to four weeks.

The photo monatage shows four pictures moving from south to north. note the difference.

South end: note height & leaves vs back ground 

here is a better example, note the foreground shorter than the back/right side

here is where you can really start seeing the difference

note the leaf expansion from photo three.  These leaves are larger.