The first significant approach emerged in the 1970s, focusing on freeze-drying. This technique, originally developed by French inventors Arsène d'Arsonval and Fréderic Bordas in 1906, gained prominence through NASA during the early days of space exploration for preserving meals. Surprisingly, it found a receptive audience among florists. Freeze-drying is a unique drying method where flowers, being essentially delicate, are first frozen. The water is then removed through sublimation, which allows it to transition directly from a solid to a gas, bypassing the liquid phase entirely. This impressive process occurs under a complete vacuum. The outcome is visually appealing, and while the flowers remain delicate, they can be preserved for several months with relative ease.
During the 1970s and 1980s, numerous patents were filed as a result of extensive research aimed at stabilizing flowers and plants. Various techniques emerged, all rooted in the same fundamental principle: substituting the plant's sap with natural glycerin. However, the methods employed varied significantly depending on the type of plant.
Stabilization through substitution
Sap consists of over 95% water and serves to transport essential nutrients and minerals for plant growth. Additionally, it helps regulate plant temperature through evaporation.
The earliest technique for stabilization, which primarily applies to leafy plants and shrubs, leverages this natural evaporation principle. Once harvested at maturity, the plants are cut and placed in a greenhouse where temperature and humidity are carefully controlled, mimicking a pleasant summer day. The stems are immersed in a mixture of water and glycerin. As the sap evaporates, the substitution liquid gradually permeates the plant, ultimately replacing the sap entirely. This process can take anywhere from one to three weeks, depending on the specific plant. Each variety also requires its own precise balance of ambient temperature, humidity, and glycerin concentration.
Stabilization through rehydration
This technique is primarily used for mosses and lichens, which are stemless plants. The process involves harvesting the plants, cleaning them, and then drying them. Rehydration for mosses is achieved by misting them with a solution of water and glycerol, heated to 40°C. For lichens, rehydration is accomplished through soaking in baths with a salt water solution. Once fully rehydrated, they are placed in a special room, where under carefully controlled conditions, the excess water will vaporize.
Glycerin, also known as glycerol, is a substance commonly found in various cosmetic products. Glycerin is included in these formulations due to its exceptional moisturizing, protective, and nourishing properties. Additionally, it serves as a culinary additive, where its emulsifying qualities are particularly valued. This refers to its ability to blend with other liquids and stabilize the resulting emulsion.
The primary advantage is its longevity. While living plants may last only a few weeks, stabilized plants can endure for several years. They maintain their appearance, flexibility, and freshness without requiring any care – no more watering, treatments, or maintenance needed. It is recommended to keep them indoors in a temperate environment, shielded from direct sunlight, and within the normal humidity range of a living space, between 20% and 80%.
Another benefit is that, free from maintenance demands, stabilized plants can inspire creativity among designers, decorators, and interior architects. They encourage innovative layouts and decor, such as green walls, green frames, furniture, and decorative items. Stabilized plants can seamlessly adapt to various living and working spaces, providing a natural and botanical atmosphere that promotes well-being without any hassle.
This is a very relevant question. Let’s compare a living plant with a stabilized one. First, we should consider the entire lifecycle of the plant from the field to its final destination in a decorative arrangement. For living plants, the loss rate is quite high, reaching approximately 80%. This means that out of 100 harvested plants, only 20 will actually be suitable for decoration. This unfortunate statistic highlights the fragility and sensitivity of living plants, which must be packaged, stored, transported under controlled conditions (especially for flowers), unpacked, arranged, sold, and frequently replaced.
In contrast, stabilized plants follow a reversed 20/80 rule. Out of 100 harvested plants, 80 are effectively utilized for decoration. The reason for this is clear: the facilities that stabilize the plants are located right where they are grown, allowing preservation processes to begin immediately. As a result, these plants experience minimal stress during transport and, once installed, can last for several years without the need for frequent replacements.
Another ecological advantage of stabilized plants is that once they are set in place, they no longer require any resources: no water, fertilizers, or treatment products.