Cannabis cultivation temperature: tips and tricks for healthy plants

Cannabisanbau Temperatur: Tipps und Tricks für gesunde Pflanzen

Niklas Bergmann, M.A.

Biochemist, specialist author

Inhaltsverzeichnis: Cannabis cultivation temperature: tips and tricks for healthy plants

When growing cannabis, there are many factors that can influence the success of your plants. One of the most crucial factors is temperature. But why is temperature so important? Quite simply, cannabis is a sensitive plant that reacts very strongly to fluctuations in its environment.

Temperature influences several critical processes in the plant:

  • Photosynthese This process, in which the plant converts sunlight into energy, works most efficiently at certain temperatures. Temperatures that are too high or too low can slow down photosynthesis and thus impair the plant's growth.
  • Transpiration This is the process by which the plant loses water through its leaves. An optimal temperature helps the plant to regulate this water loss and prevents it from drying out or losing too much water.
  • Enzymaktivität Enzymes are responsible for many biochemical processes in the plant. They work best at certain temperatures and are essential for the healthy growth and development of the plant.

Maintaining a constant and optimal temperature during the various stages of cannabis growth can make the difference between a healthy, high-yielding plant and one that suffers from stress and yields less. With the right temperature control, you can ensure that your plants realise their full potential and produce high-quality Flowers.

The importance of temperature for cannabis cultivation

Temperature is a key factor in the cultivation of cannabis, as it influences numerous physiological processes in the plant. A well-controlled temperature ensures healthy growth and a high quality harvest. Here are the most important aspects that are influenced by temperature:

Influence of temperature on photosynthesis

Photosynthesis is the process by which plants utilise light energy to convert carbon dioxide and water into glucose and oxygen. This process is essential for plant growth and development. Temperature has a direct influence on the efficiency of photosynthesis:

  • Optimum temperatures Photosynthesis reaches its maximum efficiency between 20-30°C. Within this range, the plant can utilise the light energy most effectively.
  • Excessively high temperatures Temperatures above 35°C can damage the enzymes involved in photosynthesis. This leads to a reduction in the rate of photosynthesis and thus to slower growth.
  • Temperatures too low Below 15°C, photosynthesis slows down as the chemical reactions take place more slowly. This can lead to a decline in growth and reduced vitality of the plant.

Influence of temperature on transpiration

Transpiration is the process by which water evaporates through the leaves of the plant. This is important for the plant's water balance and nutrient uptake:

  • Wasserhaushalt : At the optimum temperature, the plant can regulate its water loss through transpiration well. This prevents both dehydration and overwatering.
  • Nährstoffaufnahme Transpiration : Transpiration supports the transport of nutrients from the soil to the leaves. An optimum temperature ensures that this process takes place efficiently.
  • Temperatures too high : If the temperatures are too high, the transpiration rate increases. This can lead to excessive water loss, which stresses the plant and affects its health.
  • Temperatures too low : If temperatures are too low, transpiration slows down. This can lead to the plant absorbing less water and nutrients, which impairs growth.

Influence of temperature on enzyme activity

Enzymes are proteins that catalyse chemical reactions in the plant. They are crucial for many processes that control the growth and development of the plant:

  • Optimum temperatures Most enzymes in cannabis plants work best at temperatures between 20-30°C. In this range, the biochemical processes in the plant run efficiently.
  • Temperatures too high Temperatures above 35°C can denature enzymes, which means that they lose their structure and no longer function. This can lead to a failure of important metabolic processes.
  • Temperatures too low Below 15°C, enzyme activity slows down considerably. This can hinder the plant's metabolic processes and lead to reduced growth.

Optimal temperature for cannabis cultivation in the growth phases

The temperature requirements of cannabis plants vary depending on the growth phase. It is important to adjust the temperature accordingly to ensure the best possible growth and flower production. Here are the optimal temperatures for the different stages of cannabis cultivation:

Vegetative phase

The vegetative phase is the time when the cannabis plants mainly develop leaves, stems and roots. This phase is crucial for creating a strong and healthy plant structure that will later bear the Flowers.

  • During the day: 22-28°C

    • Optimal conditions Within this temperature range, the plants can photosynthesise efficiently and grow quickly. A temperature of 22-28°C provides the ideal environment for the development of robust stems and healthy leaves.
    • Wachstumsförderung These temperatures promote rapid cell division and strong vegetative growth, which lays the foundation for a high-yielding flowering phase.
  • At night: 18-24°C

    • Temperaturabsenkung : Slightly lowering the temperature at night in the range of 18-24°C helps to mimic the natural day-night cycle that cannabis plants would experience in their natural environment.
    • Stressreduktion : This night-time temperature reduction reduces stress for the plants and promotes healthy recovery and regeneration, resulting in stronger plants overall.

Blütephase

The flowering phase is the most important phase of cannabis cultivation, as this is when the Flowers (buds) are produced, which are the main benefit of the plant. During this phase, the temperature requirements change slightly to maximise the quality and quantity of the Flowers.

  • During the day: 20-26°C

    • Blütenentwicklung A temperature range of 20-26°C is ideal for flower formation. In this range, the plants can efficiently absorb nutrients and invest in flower production.
    • Terpene and cannabinoid production These temperatures promote the production of terpenes and cannabinoids, the chemical compounds responsible for the odour, taste and effects of cannabis. A slightly cooler area than in the vegetative phase can improve the quality of the Flowers.
  • At night: 16-22°C

    • Temperaturabsenkung A night-time temperature of 16-22°C helps the plant to save energy and optimise metabolic activities. This helps to promote flower development and keep the plant healthy.
    • Farbentwicklung In some cannabis strains, a cooler night-time temperature can stimulate the development of anthocyanins, which can lead to a more intense colouring of Flowers. This can increase the aesthetic appeal and market value of Flowers.

By optimising the temperatures during the different growth phases, you can maximise the growth of your cannabis plants and improve the quality and quantity of the harvest. Be sure to monitor temperatures regularly and adjust if necessary to achieve the best results.

Temperature control when growing cannabis

Controlling the temperature is a crucial factor in the successful cultivation of cannabis. There are several methods and devices that can help you maintain the optimal temperature in your grow room. Here are some important aspects of temperature control:

Ventilation systems for temperature control

An efficient ventilation system is essential to regulate the temperature and air quality in your grow room.

  • Abluftventilatoren These help to remove the warm, stale air from the growing space and bring in fresh, cooler air. A well-placed exhaust air system ensures that the temperature remains constant and prevents heat build-up.
  • Umluftventilatoren These fans distribute the air evenly in the room, prevent hotspots and ensure that all plants receive even air circulation. This not only supports temperature control, but also strengthens the plant stems.

Use of air conditioning and heating

Depending on the climatic conditions of your growing location, the use of air conditioning and heating systems may be necessary.

  • Klimaanlagen They are particularly useful in hot climates or during the summer months. Air conditioners can quickly and efficiently lower the room temperature and keep it at a constant level.
  • Heizungen In colder climates or during the winter months, heaters may be necessary to keep the temperature at an optimum level. There are special heaters for growing rooms that ensure even heat distribution.

Important measuring devices: Thermometer and hygrometer

Reliable measuring devices are essential to accurately monitor temperature and humidity.

  • Thermometer Digital thermometers are the most accurate and easy to use. They display the current temperature and many models also offer a memory function for maximum and minimum values.
  • Hygrometer These devices measure the humidity in the growing room. As temperature and humidity are closely linked, it is important to check both values regularly to ensure an optimal growing climate.

Light sources and their influence on temperature

The choice of light source has a significant influence on the temperature in your grow room.

  • LED-Lampen These are energy-efficient and generate less heat compared to conventional HPS or MH lamps. They are ideal for use in smaller rooms or in hot climates as they have less impact on the temperature.
  • HPS and MH lamps These traditional lamps are effective, but they generate a lot of heat. In rooms where these lamps are used, good ventilation and possibly the use of air conditioning is necessary to control the temperature.
  • Positioning the lamps The height and position of the lamps can also influence the temperature. It is important to position the lamps so that they illuminate the plants evenly without overheating them.

By combining these methods and devices, you can effectively control the temperature in your grow room and create optimal growing conditions for your cannabis plants. Be sure to monitor the temperature regularly and make adjustments to achieve the best possible results.

Common problems and solutions for temperature control

Temperature control is essential for successful cannabis cultivation. Despite all precautions, problems can sometimes occur. Here are some common temperature problems and their solutions:

Too high temperatures in cannabis cultivation

High temperatures can seriously affect the health and growth of your cannabis plants. Here are the most common symptoms and the corresponding solutions:

Symptoms and effects

  • Hitzestress : Plants show symptoms such as drooping leaves, discolouration (often yellow or brown) and burnt leaf tips.
  • Reduced photosynthesis : Excessively high temperatures can reduce the photosynthesis rate, which leads to slower growth.
  • Increased perspiration : High temperatures lead to excessive transpiration, which can dry out and stress the plants.
  • Wachstumsstörungen : The plants can remain small and appear weaker overall.
  • Blütenqualität : Excessively high temperatures during the flowering phase can impair the quality and density of Flowers.

Lösungsansätze

  • Improving ventilation Install additional exhaust fans to remove the warm air from the growing space more efficiently. Ensure a sufficient supply of fresh air.
  • Use of air conditioning systems : In particularly hot climates, air conditioning may be necessary to keep the temperature at an optimum level.
  • Adjust light sources : Use LED lamps that generate less heat and increase the distance between the lamps and the plants.
  • Schattierungsnetze : In outdoor cultivation, shading nets can help to reduce direct sunlight and thus lower the temperature.
  • Adjust night cycle : Shift the lighting cycle so that the lighting takes place during the cooler night hours.

Temperatures too low for cannabis cultivation

Low temperatures can also have a negative impact on the growth and health of your cannabis plants. Here are the most common symptoms and the corresponding solutions:

Symptoms and effects

  • Wachstumsverlangsamung : At low temperatures, the metabolic processes slow down, which leads to slower growth.
  • Farbveränderungen Plants can take on a purple or blue colour, especially on the stems and leaf veins.
  • Reduced nutrient intake : The roots absorb fewer nutrients at low temperatures, which can lead to deficiency symptoms.
  • Blütenqualität : During the flowering phase, low temperatures can affect the production of terpenes and cannabinoids.

Lösungsansätze

  • Use of heaters Use heaters to raise the temperature in the growing space. Make sure that the heaters are evenly distributed to ensure consistent heat distribution.
  • Insulation of the growing space Improve the insulation of the growing space to minimise heat loss. Tightly sealed doors and windows help to retain heat.
  • Wärmematten : Heat mats placed under the pots can increase the soil temperature and keep the roots warm.
  • Adjust light cycles Extend the lighting duration to utilise the additional heat from the lamps. Make sure that the plants still receive sufficient dark phases.
  • Additional light sources Install additional light sources that can provide both light and heat, such as HPS lamps.

By identifying and fixing temperature issues, you can ensure that your cannabis plants grow in optimal conditions. Regular monitoring and adjustments are key to successful cultivation and a high-quality harvest.

Special temperature requirements for different cultivation steps

In cannabis cultivation, there are specific temperature requirements for different steps of the process. Here are the optimal conditions for germinating, drying and decarboxylating cannabis.

Cannabis germination temperature

Optimal conditions for germination

Germination is the first step in the life of a cannabis plant, and temperature plays a crucial role in ensuring that seeds germinate successfully.

  • Temperaturbereich : The optimum temperature for the germination of cannabis seeds is between 20-25°C.
  • Konsistenz Keep the temperature constant within this range to achieve the best germination rates. Fluctuations can delay the process or impair germination.
  • Feuchtigkeit : In addition to the temperature, high humidity (around 70-80%) is important to provide the seeds with sufficient moisture.
  • Lichtverhältnisse : During germination, the seeds do not need direct light. A dark or slightly dimmed area is ideal.

Cannabis drying temperature and humidity

Optimal conditions for drying

Drying cannabis is a critical step in preserving the quality and potency of Flowers. Temperature and humidity must be carefully controlled to avoid mould growth and cannabinoid degradation.

  • Temperaturbereich : The ideal temperature for drying cannabis is between 18-24°C.
  • Luftfeuchtigkeit Relative humidity of 45-55% is ideal. Humidity that is too high can promote mould growth, while humidity that is too low causes the Flowers to dry out too quickly and lose its flavour.
  • Luftzirkulation Good air circulation is important in order to remove moisture evenly. However, avoid direct ventilation on the Flowers to prevent it from drying too quickly.
  • Dunkelheit : Dry the Flowers in a dark room to prevent the degradation of cannabinoids and terpenes by light.

Decarboxylate cannabis temperature

Temperature range for decarboxylation

Decarboxylation is a necessary step to convert the inactive acids (THCA and CBDA) into their active forms (THC and CBD). This is particularly important for the production of edible cannabis products or extracts.

  • Temperaturbereich : The optimum temperature for decarboxylation is between 105-115°C.
  • Dauer : At this temperature, the process takes about 30-45 minutes to ensure that the cannabinoids are fully activated.
  • Uniform heating Make sure that the cannabis flowers or concentrate are heated evenly. A baking tray with baking paper can help to distribute the heat evenly.
  • Überwachung : Monitor the process closely to avoid overheating, as too high temperatures can destroy the cannabinoids and terpenes.

By adhering to these special temperature requirements in the various cultivation steps, you ensure that your cannabis plants grow healthy, the Flowers are of high quality and the active ingredients are optimally activated.

Outdoor cultivation of cannabis and temperature adaptation

When growing cannabis outdoors, natural climate conditions play a crucial role. Here are the optimal temperatures and some important considerations to ensure your plants thrive outdoors.

Growing cannabis outdoors: Optimal temperatures

Consideration of local climate conditions

When growing cannabis outdoors, it is important to consider the natural climatic conditions of your location. Here are the general temperature requirements:

  • Tagsüber : The optimum temperature for growing cannabis outdoors is between 18-30°C during the day.
    • Wachstumsphase : During the vegetative growth phase, cannabis plants prefer temperatures at the upper end of this range (24-30°C) in order to grow vigorously.
    • Blütephase : In the flowering phase, temperatures should be slightly cooler (18-26°C) to promote the production of terpenes and cannabinoids.
  • Nachts : Temperatures should not fall below 12°C at night.
    • Avoiding stress Too great a drop in temperature can stress the plants and slow down growth. Ideally, night temperatures should be between 15-20°C.

Measures to adapt to local conditions

  • Protection against extreme temperatures In hot climates, the use of shading nets can help to protect the plants from excessive heat. In colder regions, putting up windbreaks or wrapping the plants in fleece can help protect them from the cold.
  • Wasserverwaltung : In very hot areas, plants may need to be watered more frequently to prevent dehydration. Mulching can help to maintain soil moisture.
  • Bodenqualität : The soil should be well drained and rich in nutrients to provide the plants with optimal growing conditions.

Optimal seedling temperature

Conditions for healthy seedlings

Seedlings are particularly sensitive to fluctuations in temperature and humidity. To grow healthy and strong seedlings, the following conditions are ideal:

  • Temperaturbereich : Seedlings thrive best at temperatures between 20-25°C.
    • Konsistenz : Keep the temperature constant within this range to promote even and rapid growth.
  • Luftfeuchtigkeit High humidity of around 70-80% is ideal for seedlings. This helps to minimise water loss and support healthy growth.
  • Lichtbedingungen Make sure the seedlings get enough light, but avoid direct sunlight that could burn them. A sheltered area with indirect sunlight or the use of grow lights can help.

Schutzmaßnahmen

  • Mini-Gewächshäuser Small greenhouses or clone domes can help control the temperature and humidity for seedlings and protect them from extreme weather conditions.
  • Isolierung : In colder night temperatures, insulating materials such as fleece blankets can be used to keep the seedlings warm.
  • Lüftung : Ensure good ventilation to prevent mould and disease, especially in high humidity.

By observing these temperature requirements and protective measures, you can ensure that your cannabis plants thrive outdoors and produce healthy, high-yielding harvests.

Hemp temperature outdoor at night

The night-time temperature plays a decisive role in the outdoor cultivation of cannabis. Night temperatures between 15-20°C are ideal, as the plant's metabolic processes work well in this range and flower development is promoted. A drop below 12°C can stress the plants, slow down growth and impair harvest quality.

However, cooler night temperatures can also offer advantages for some varieties by promoting the formation of purple and blue colour pigments, which makes the Flowers more attractive. However, caution is advised: Excessive cold can damage the plant.

In colder climates, protective measures such as fleece blankets, windbreaks and layers of mulch can help to keep the heat around the plants. During particularly cold nights, outdoor heaters can also be used to ensure a constant temperature. Proper temperature control ensures stress-free plant development and a high-quality harvest.

Fazit

Summary of the most important points on temperature in cannabis cultivation

Temperature is one of the most important factors for the successful cultivation of cannabis. Here are the most important points you should consider:

  • Temperature in the growth phases :
    • Vegetative phase : 22-28°C during the day, 18-24°C at night
    • Blütephase : 20-26°C during the day, 16-22°C at night
  • Temperaturkontrolle :
    • Efficient ventilation systems for regulating the room temperature
    • Use of air conditioning and heating systems as required
    • Use of thermometers and hygrometers for accurate monitoring
    • Selecting the right light sources to minimise heat production
  • Problemlösungen :
    • Measures to reduce excessively high temperatures, such as improved ventilation and air conditioning
    • Measures to increase temperatures that are too low, such as heaters and better insulation
  • Special cultivation steps :
    • Germination: 20-25°C and high humidity
    • Drying: 18-24°C and 45-55% humidity
    • Decarboxylation: 105-115°C for the activation of cannabinoids
  • Outdoor-Anbau :
    • 18-30°C during the day and not below 12°C at night
    • Protective measures for extreme conditions
    • Optimal conditions for seedlings: 20-25°C and high humidity

Tips for successfully growing cannabis

  • Regular monitoring : Monitor the temperature and humidity regularly to ensure that they remain within the optimum ranges.
  • Flexibility and customisation Be prepared to adapt your growing conditions to respond to changing environmental conditions. Utilise technologies such as air conditioning, heating and ventilation systems effectively.
  • Invest in quality : High-quality equipment such as precise thermometers, hygrometers and efficient lighting systems can make the difference between an average and an outstanding harvest.
  • Schritt-für-Schritt-Vorgehen : Be sure to consider the specific temperature requirements at each stage of cultivation, from germination and growth to harvesting and drying.
  • Protection of plants : Implement measures to protect your plants from extreme temperatures, both indoors and outdoors.

With these tips and a clear understanding of temperature requirements, you can ensure your cannabis plants grow healthy and produce high-quality Flowers. Happy growing!


Niklas Bergmann, Fachautor

Freut euch auf die Insights von unserem Biochemiker Niklas Bergmann! Mit seinem tiefen Verständnis für alles, was mit Hanf zu tun hat, liefert er euch die neuesten und coolsten Infos direkt in euer Feed. Schnörkellos und klar verpackt er das komplexe Thema Cannabinoide und macht es für euch easy zugänglich. Mit Niklas an der Spitze unseres Wissens-Teams seid ihr immer top informiert.