The role of greenhouse plastic in flower quality

Before Valentine’s day flowers get to your hands, they go through cutting, selection, packaging, cold, transportation, distribution centers, and flower shops. When the journey is long (for example, when they are shipped) the margin for error is minimal: whatever stress the crops goes through in the supply chain becomes obvious when seeing the blooming, color and flowers’ lifespan.

During the month of Valentine’s day, many of the flowers that moved and arrived to the market are the exact type of flowers that we wanted to talk about: the ones that have to go through many days en route, and still then, arrive with the highest quality.

When a flower is shipped, this challenge is multiplied

Shipping is used especially for species that can withstand longer periods of transportation. For example, carnations, pom pom chrysanthemums. This tends to be because of logistical efficiency and its cost, however, it requires a lot from the flower.

During shipping, the flower does not only travel, it also “waits”, in containers, docks, delivery processes, and redistribution. After which comes the commercial operation, going to wholesalers, flower stores, or supermarkets, and finally to vases in consumers’ homes. That’s where a key question is asked: what must happen during cultivation for the flower to withstand everything that is to come?

The starting point is cultivation: lower stress, better performance once cut

The flower quality we see at the end of the road starts way before it’s packaged. For flower growers, small changes in the flowers’ environment can impact the results: temperature, radiation, temperature shifts, an excess or lack of UV light, and violent changes throughout the day.

A flower grown in more stable conditions tends to perform better post-crop, once it’s cut there is less accumulated stress and more consistent characteristics that can be better translated with better behavior during the supply chain.

Why is greenhouse plastic so influential?

Greenhouse plastic is not a generic roofing. When it is well designed for crop, it helps control the variables that define performance and quality. The most important aspect to control is light management and temperature inside the greenhouse.

In practical terms, a film can help administer three components:

• Ultraviolet (UV): affects color expression and can also influence the interaction with certain bugs
• Visible light / PAR: this is the energy that propels photosynthesis and productivity
• Infrared (IR): impacts the thermic behavior; helps reduce fluctuations and better manage the heat during the day and the loss of temperature at night.

When those variables are controlled better, the risk of damage of delicate structures is reduced (such as petals and bulbs) and a consistent yield is improved, which is essential when the journey is prolonged.

The color of the roses is also defined by light

There are some varieties where UV management is decisive. In red roses, UV light control helps prevent overpigmentation. In the case of white roses, the control of UV light helps maintain the color preventing yellowing. In other varieties, especially bicolors, allowing a higher amount of UV light can support more lively tones in the flowers.

This is not a minor static factor. An inconsistent color does not often do well in the market, and during long journeys the risk of damage increases.

Not all crops are the same: the case of alstroemeria

The alstroemeria requires light, but with high diffusion. Direct light can affect delicate structures, and the flower is sensible to harsh changes in temperature throughout the day. That’s why, in these crops films that prioritize radiation diffusion without sacrificing luminosity and help stabilize the thermal charge are vital.

At Grupo Plastilene we produce two products that tend to work well according to the objective of the producer: Green Agrolene, associated with great growth and productivity, as well as Infralene, that offers high diffusion without sacrificing light and helps reduce the risk of burning during flowering given its thermal management.

In crops it is of the utmost importance to know that having a standard solution in mind is best, each flower needs specific conditions and, given that, a special greenhouse plastic.

Insects and UV: sometimes the strategy is also “not being visible”

In some crops it is required to let certain light ranges that support pollination. In flowers, the objective is often different: protecting the flower. Depending on the crop and its management, adjusting the entrance of UV light can influence whether or not certain insects can detect the crop or not, which translates into lower attack pressure.

The final result: a flower that arrives to its final destination better than before

So, when you buy or gift a flower, you receive the result of many technical decisions. Some go through cold and packaging, yes, but many start in the greenhouse: how light was managed, how thermal irregularities can be reduced, how it avoided stress in its development and how consistency was achieved.

This is the “behind the scenes” and this is exactly where we work: so, even when the journey is long, flowers arrive in better conditions and with the market’s desired quality.