Tobacco Drying Greenhouse

Producing quality tobacco requires careful and meticulousness in every step to be taken, starting from the selection of the field. In addition, it also depends on adopting and applying the results obtained through the transfer of knowledge, manners and experiences passed from father to son and sometimes as a result of years of research.

Drying is the most important and sensitive process of tobacco farming. The slightest negligence or carelessness can lead to wasted all efforts.

What is Drying?

Drying is not only about reducing 80-85% of the water present in the tobacco leaf, which has reached the harvest maturity, to 10-15%, and as a result, the leaf color turns from green to yellow. It is necessary to see drying as a maturation process. Therefore, drying is the process of giving the harvested tobacco leaves the characteristics desired by the consumers by causing some changes in the chemical composition of the leaf under certain temperature and humidity conditions. Especially in the first stages of drying, there is an oxidation event as the leaves are breathing. With the mixing of air, not only water is lost in the leaf, but also some unwanted substances in the leaf are reduced.

Almost all of our country's tobacco is dried in the open, under the sun. In the drying process, systems such as grill (crabmandal), mirror, wagon, gazebo, which are developed depending on the climate structure of the region, are used. Therefore, the drying process takes names such as grid-type drying, wagon-type drying, etc., depending on the system used. In the Aegean region, where the summer season is hot and dry, grid-type drying is applied.

In this method of drying, strings of tobacco are placed on the grids, wrapped in lances. After the leaf blade has dried, it is taken from the grid and laid on the ground for vein drying. So; It is taken to the exhibition. During this period, tobacco strings are fully open to all kinds of climatic events day and night. In recent years, the drying process has also started to be carried out in 90 * 180 cm wire stretched frames.

Why Drying Tobacco in a Nylon Greenhouse?

It is clear that if the drying of tobacco leaves is carried out under certain temperature and humidity conditions, the result will be more favorable. Plastic covered greenhouse gains importance as it enables the control of temperature and humidity, albeit within wide limits. Because it is possible to adjust the temperature and relative humidity in the greenhouse by opening and closing the two ends of the greenhouse.

On the other hand, the plastic covered greenhouse is absolutely protective against weather events such as precipitation, dew, wind, etc. that may be seen during drying, which negatively affect drying and necessarily require precautionary measures. Drying tobacco in a plastic covered greenhouse is a means of obtaining higher quality products and creating a more comfortable working environment for the producer.

What is Plastic Covered Greenhouse?

The plastic covered greenhouse is simply pulling plastic cover over the grid and the exhibition place with the help of iron rods or, conversely, setting up a grid under this plastic cover and preparing the exhibition space.

Required Materials for 100 m² Plastic Covered Greenhouse:

According to the observations and calculations made; 100 m² plastic covered greenhouse under Aegean Region conditions. It is sufficient to dry the tobacco obtained from an area of 8–10 decares (for grill and exhibition). The material required for a plastic covered greenhouse of this size has been found below.

1--30 pieces of 12 or 14 mm rebar, each 6 m long

2--60 pieces, each 30-40 cm tall, half finger, galvanized pipe,

3--64 wooden stakes,

4--30 pieces, each 4 or 5 m long plastic hoses (ordinary garden hose),

5-30 pieces of plastic irrigation hoses, each 8-9 m long, 6-7 cm wide (double layer),

6--34 m tall (about 25 kg), single layer of 6 m wide cover white plastic

7-Known, other materials used in the classic grill. ***

Establishing a Plastic Covered Greenhouse

- The place where the plastic-covered greenhouse is to be installed should be in the open, sun-dried places, closed to winds, with plenty of sunshine, and the south side and the bottom should be filtered soil. If we build the facility close to the ground water, we cannot get rid of the soil moisture. Although the direction is determined, it is beneficial to install it in the direction of the prevailing winds so that the greenhouse is not torn by the blowing winds, the temperature is the same all over the greenhouse and we can control the humidity and temperature in the greenhouse.

- There should be 60-65 cm between the bottom soil of the sparrow-grid-crusher that we will install in the drying facility and the spreader wire. The height of the nylon greenhouse should be around 1.65-1.75 m.

- The ground of the place where the drying greenhouse will be installed is pressed, the measurements are made and the area where the tunnel will sit (approximately 4x30 m rectangular area) is determined with the help of piles to be driven into 4 corners.

—Iron rods (rebars) are inserted into the garden hoses and brought in a semicircle so that the bare part remains equidistant from both ends. The garden hose on the iron prevents the plastic of the cover from sticking to the iron in hot weather.

- Galvanized water pipes with pointed ends are nailed on two lines formed in a gap (approximately 375 cm) between the two ends of the prepared iron rods, 1 meter apart.

- The skeleton of the greenhouse is formed by inserting the ends of the semicircular irons into the water pipes that are nailed to the ground.

—In a windless day, the cover is pulled over the plastic nylon frame, the eaves on both sides are equalized and buried in the ground thoroughly.

- Wooden stakes are piled between 2 pipes, 2 pieces of which are 50-60 cm apart, in a way that they are 40-50 cm outside of the galvanized pipes that serve as carrier feet. Plastic irrigation hoses, which will act as a tensioner to prevent the cover from venting and flying, by driving 2 piles on both ends of the tunnel, are passed crosswise over the tunnel and their ends are tightly tied to the wooden piles. This process is sufficient if it is done by jumping one by one, starting between the first two iron bars.

- The two-meter part of the cover plastic, which is increased at both ends of the greenhouse, is attached to the wooden stakes at the end of the greenhouse so that it can close the mouth of the greenhouse when necessary.

The tobacco will be ready for drying with the grid we will adjust the width according to the length of the pike in the greenhouse, whose assembly is finished.

Drying Tobacco in Plastic Covered Greenhouse

In order to get good results from drying tobacco in the greenhouse, the tobacco to be dried must definitely be broken during the period when they reach harvest maturity, even 1-2 days after this period. Early (semi-maturity or lighter) harvest should definitely be avoided. For tobacco grown in strong soils, the slaughter should be done with a delay. Crimean work should be done manually. Since the same leaves will come together in hand by hand in terms of size, body and vitality, color uniformity is ensured in the drying process.

It should not be dried in the greenhouse, as it gives better results if it is dried on the grill without withering, with the hands open. The tobaccos that are lined up and scrapped on the pike should not be transported into the greenhouse suddenly after the withering process, at noon when the hot sun is dominant, or in very windy weather. Because the water in the leaves evaporates in a short time. In the meantime, since the chlorophyll, which gives the green color to the leaf, cannot be broken down completely, the leaf color does not turn into light greenish-yellow, but remains green.

Mother's tobacco should be placed in the greenhouse for 1–1.5 days, after withering the tip and bottom hands for 1.5–2 days, depending on the humidity. The withering time should be longer as you go from the lower hands to the upper hands. During the drying of the tobacco, the temperature and humidity in the greenhouse should definitely be controlled, and the temperature and relative humidity should be adjusted according to the drying levels of the tobacco in the greenhouse (since the tobacco displayed at the same time in the greenhouse, the tobacco that has almost completed the waiting period in the grill, the tobaccos that have just been put on the grill can be found together). should be studied. If the excess moisture cannot be evacuated, our product will dry as red-brown and even rotting may be seen, since the percentage of moisture will be higher.

In case the temperature and humidity rise and fall, both ends of the greenhouse should be opened completely and the desired environment in the greenhouse should be provided. Under normal conditions, one end of the greenhouse that does not receive wind must be kept open.

The greenhouse protects the drying tobacco from possible rain or dew or wind. However, the necessary temperature and humidity controls must be made to provide a suitable environment in terms of temperature and humidity for the tobacco inside.

Color determination is started when the leaves become lemon yellow and still have a slightly greenish appearance. The transition cycle between withering and leaf blade drying is a very delicate task. When the desired color is seen, the humidity is decreased and the temperature is increased. Care is taken to ensure that drying occurs as quickly as necessary in order to prevent oxidations that lead to red-brown colors and to kill the tissue.

During the drying of the leaf blade, the temperature inside the greenhouse may rise up to 60 ° C, the air humidity rate drops to 20%. In nylon drying greenhouses, one side should be opened normally to reduce the air humidity.

After the leaf blade has dried, the spikes are laid on the soil and the middle and side veins are dried. At this stage, the temperature inside can rise up to 70 ° C. The vessel drying phase takes 18–24 hours.

Temperature, humidity rates and drying phases may vary depending on the type of tobacco to be dried, the place where it is grown and the year.

Some drying malfunctions may occur in this type of drying. During the drying phase of the leaf blade, if the excess moisture in the greenhouse is not drained as quickly as necessary, brown spots occur on the leaves, especially on fine-textured leaves.

Dents on green leaves cause malfunctions in the form of green spots or spots. In dents made after the yellowing phase, the color remains as light brown after drying.

Tobaccos dried in greenhouses dry in 4-6 days less than those dried in the open. In Denizli, under normal summer conditions, the main hands dry in 6-8 days and the end hands in 10-12 days. It can be taken for an average of 8 days.

The tobaccos dried in the open grill and in the greenhouse were examined while in series, and it was observed that the tobaccos dried in the greenhouse were more homogeneous, light greenish-yellow, and the A Grad percentage was higher than the tobacco dried in the open greenhouse. In addition, as the drying time was shortened, the loss of dry matter was less. With this drying method, where the installation cost is not too much, the drying problems of the tobacco in the early autumn rains and the cooling of the air are largely eliminated, especially for the tip and end hands. The fact that the dried tobacco will not be affected by external factors such as wind, rain and dew gives great comfort to the producers. Tobaccos dry out as summer dry.

In this drying method, which started and became widespread in the Aegean Region production areas in the 1990s, a 100 m² tobacco drying greenhouse where greenhouse nylon can be used for 2-3 years is approximately 600 TL with the prices in 2012.

*** Ministry of Agriculture, Aegean Agricultural Research Institute A.USTURALI-Dr.G. AUTHOR-Dr.R. APTI-Dr.H. OTAN Tobacco Drying in High Tunnel with Plastic Cover