In the production of ornamental plants, such as potted roses and Kalanchoe, it used to be quite common to utilize chemical growth regulators such as Bonzi, to reduce internodal stretch. These chemicals have come under increasing scrutiny in a number of markets.
One of the more innovative ways in which growers try to achieve compact plants is to utilize the benefits of “blue light”. This is possible with LED and also with new plasma lamps. And it works. But it requires a substantial investment in new horticultural lighting systems, which is not always easy to justify in these challenging times.
Therefore we now take a look at some growers who have gone one step further than “blue light” (for example 400 nm). They have proceeded to look at certain forms of UV light, such as those supplied by CleanLight (260 nm). A respected grower of young plants plants (strawberrey, leek, etc) in Holland, Mr. PietHein Kapiteijns, explains: “When we started with CleanLight back in 2009, we did so to protect our young plants against microbials such as PowderyMildew, Rust, Botrytis, and the Xanthomanas bacterium. It worked: our plants showed lower leves of microbials, and at the same time, we were able to reduce and/or eliminate the use of chemical pesticides. But we also noticed that our plants became more vital, showed a darker stronger leaf, and displayed a more compact form. Prior to using CleanLight we had to top our plants through mowing. After implementing CleanLight this was no longer necessary”.
The treatment involves a daily application
Today, this technology is also applied successfully by some of the larger producers of medical cannabis in North America. Arne Aiking of CleanLight expands: “In that industry we also saw originally that growers chose for CleanLight as a non-chemical way to control powderymildew, but as the industry matures we see a desire for heavier more compact plants in that industry as well”.
This picture, taken at a large Licensed Producer in Canada, shows how CleanLight is applied in combination with LED lights to give young plants a healthy start in life, with full spectrum light comparable to what they would have received in an outdoor setting. That means strong vital plants, low levels of microbials, higher levels of desirable phytochemicals such as CBD, and more compact growth with shorter internodal stretch.
Accountmanager at CleanLight, Arjo VanderSluis adds: “Originally we supplied these systems mostly to ornamental growers to control diseases and to provide for a stronger more compact plant. Today, we see that an increasing number of producers of medical cannabis also see these benefits, not only in terms of crop protection, but also in terms of growth regulation.”