A greenhouse offers you the unique opportunity to optimise the environmental conditions for growing cannabis. Unlike outdoor cultivation, where you are at the mercy of the weather, you can precisely adjust the temperature, humidity and light in a greenhouse. This leads to even and healthy growth of your plants.

Temperature control is particularly important as cannabis is sensitive to extreme heat or cold. With a greenhouse, you can keep the temperature constantly in an optimal range, which leads to better photosynthesis and ultimately higher yields. You can also regulate the humidity to prevent mould and other moisture problems.

Light is another decisive factor. In the greenhouse, you can ideally control the light conditions and use additional lighting to supplement the natural sunlight if necessary. This is particularly important in the shorter winter months so as not to interrupt growth and to provide the plants with a constant light cycle.

Extended growing season thanks to the greenhouse

A greenhouse allows you to significantly extend the growing season. While traditional outdoor cultivation is heavily dependent on the seasons, in a greenhouse you can start growing in early spring and harvest until late autumn. This gives you the freedom to carry out several growing cycles per year and maximise your harvest yields.

Thanks to the sheltered environment in the greenhouse, you can stay active even in colder months. The insulation keeps the heat inside so that the plants can thrive even at lower outside temperatures. You can also put the plants outdoors earlier or bring them into the greenhouse later to create the best conditions for each stage of growth.

The extended growing season also gives you the opportunity to try out different cannabis strains, which may have different flowering times. This allows you to be flexible with your growing plans and always get the best out of each season.

Protection from external influences when growing cannabis in a greenhouse

Another major advantage of growing cannabis in a greenhouse is the protection from external influences. Outdoors, your plants are exposed to many dangers, such as heavy rain, wind, pests and diseases. A greenhouse creates a barrier against these harmful influences and provides a controlled and safe environment for your plants.

Heavy rainfall can oversaturate the soil and suffocate the roots of your plants. Wind can damage or knock over the plants, while pests such as insects and rodents can eat the plants and transmit diseases. You are better protected from all these dangers in a greenhouse. The plants are safer and can concentrate fully on their growth, resulting in better quality and higher yields.

In addition, a greenhouse also offers protection from prying eyes and possible theft, which is particularly important if you live in an area where cannabis cultivation is not widespread or possibly even illegal. With a greenhouse, you can grow discreetly and safely without attracting unwanted attention to your plants.

The right equipment for growing cannabis in a greenhouse

Choosing the right greenhouse for cannabis

Choosing the right greenhouse is the first and most important step in successfully growing cannabis. There are various types of greenhouses that differ in size, material and structure. Glass and polycarbonate greenhouses are mainly suitable for growing cannabis, as they offer high light transmission and good insulation.

When choosing the size of the greenhouse, you should make sure that it offers enough space for the number of plants you want to grow. A greenhouse that is too small can quickly become overcrowded and restrict the plants in their growth. At the same time, however, it should not be too large in order to keep the costs and effort for heating and lighting within limits.

Another important aspect is ventilation. Greenhouses with good ventilation systems allow better control of humidity and temperature. Automatic ventilation systems that open and close at certain temperatures are particularly practical.

Additional lighting for cannabis in the greenhouse

Even though a greenhouse provides plenty of natural light, additional lighting may be necessary, especially in the darker months. Cannabis requires a certain amount of light per day to grow and flower optimally. This is where LED lights come into play, as they have proven to be particularly energy efficient and effective.

LED lamps are available in different spectra and can therefore supplement natural sunlight. During the growth phase, plants require more blue light, while red light is favoured during the flowering phase. Modern LED systems make it possible to adjust the light spectrum according to the needs of the plants.

The lighting should be evenly distributed to ensure that all plants receive sufficient light. Reflective materials on the walls of the greenhouse can help to distribute the light evenly and increase efficiency.

Ventilation and air circulation in the cannabis greenhouse

Good ventilation and air circulation are crucial to the success of your greenhouse cannabis grow. Stagnant air can lead to a variety of problems, including mould growth and pest infestation. Therefore, it is important to install an effective ventilation system.

A ventilation system should include both supply and exhaust air fans. Supply air fans draw fresh air into the greenhouse from outside, while exhaust air fans transport stale air outside. These fans should ideally be equipped with filters to keep out dirt and pests.

In addition to ventilation, air circulation fans ensure that the air inside the greenhouse remains in motion. This prevents the formation of damp patches and ensures that the plants are evenly supplied with CO2, which is necessary for photosynthesis.

Irrigation systems for growing cannabis in the greenhouse

An efficient irrigation system is essential for the successful cultivation of cannabis in the greenhouse. Drip irrigation systems are particularly popular as they ensure an even and precise water supply. These systems deliver water directly to the roots of the plants, saving water and minimising the risk of overwatering.

Automatic irrigation systems are particularly practical, as they reduce the effort involved and ensure that the plants always receive the right amount of water. These systems can be set to deliver water at specific times or depending on soil moisture.

In addition to irrigation, the supply of nutrients is also important. In hydroponic systems, the plants are grown in a nutrient solution instead of soil. This method can lead to faster growth and higher yields, but requires precise control of the nutrient concentration and pH value.

Growing and caring for cannabis in a greenhouse

Selection of suitable cannabis varieties for the greenhouse

Choosing the right cannabis strains is crucial to the success of your greenhouse cultivation. Not all strains are equally suitable for greenhouse cultivation. Sativa-dominant strains tend to grow taller and benefit from the extended growing period and space available in the greenhouse. However, they require more care and a longer flowering period. Indica-dominant varieties, on the other hand, remain more compact and have a shorter flowering time, which makes them easier to care for.

Autoflowering strains, which flower independently of the light cycle, are also a good choice for greenhouses. They generally have a shorter lifespan and can produce several harvests per year. When selecting varieties, you should also pay attention to the specific requirements and characteristics, such as resistance to mould and pests, which can be particularly beneficial in a humid greenhouse environment.

Soil preparation and fertilisation for cannabis in the greenhouse

Careful soil preparation is the be-all and end-all for healthy cannabis plants. The soil should be loose and well aerated to allow optimal root growth. High-quality soil, rich in organic matter and nutrients, forms the basis for strong plants. Many gardeners mix their own soil to ensure that it contains all the necessary nutrients.

Compost, worm humus and well-rotted manure are excellent additions to increase soil fertility. It is also important to check the pH of the soil and adjust it if necessary to ensure that nutrients are available for the plants. A pH between 6.0 and 7.0 is ideal for cannabis.

Regular fertilisation is also essential. During the growth phase, plants need more nitrogen, while they require more phosphorus and potassium during the flowering phase. Organic fertilisers are particularly gentle and support soil life, but mineral fertilisers can also be used to quickly compensate for specific nutrient deficiencies.

Planting time and regular care of cannabis in the greenhouse

The right planting time is crucial for the success of your cultivation. In a greenhouse, you can start growing in early spring when the days get longer and the temperatures rise. Germination is best done in small pots or growing cubes placed in a warm and humid environment. As soon as the seedlings are strong enough, they can be planted in larger pots or directly in the greenhouse soil.

Regular care is the secret to healthy and productive plants. This includes regular watering, making sure that the soil is evenly moist but not too wet. Too much moisture can lead to root rot, while drought stress can impair plant growth.

Pruning and defoliating the plants promotes air circulation and the penetration of light into the interior of the plant, which leads to better flower formation. During the growth phase, side shoots should be removed to concentrate the plant's energy on the main shoots. During the flowering phase, it is important to remove dead leaves regularly to prevent mould growth.

Pest control is another important aspect of care. Even though the greenhouse offers some protection, pests such as spider mites, aphids and thrips can still cause problems. Regular inspections and the use of biological pesticides can help to keep the plants healthy.

Cannabis in the greenhouse odour

Preventing odour problems in cannabis cultivation

When growing cannabis in a greenhouse, the intense smell of the plants can be a significant problem, especially if your greenhouse is close to neighbours or public areas. Cannabis produces strong, distinctive aromas during the flowering period that can be easily recognised. These odours come from the terpenes, the aromatic compounds in the plants that are also responsible for their therapeutic properties.

To prevent odour problems, it is important to make the greenhouse airtight. All cracks and openings should be sealed to prevent the odour from escaping. Special sealing materials and techniques can help to make the greenhouse as odour-tight as possible.

Another important step is the installation of a high-quality exhaust air system. This system should be capable of efficiently filtering and renewing the air in the greenhouse without the odour escaping to the outside. Activated carbon filters are particularly effective here, as they neutralise odours before the air reaches the outside.

Tips for controlling odours in the greenhouse

In addition to sealing and using exhaust air systems, there are other measures you can take to control odours in the greenhouse. Here are some tips:

Aktivkohlefilter These filters are one of the most effective methods of odour control. They work by binding and neutralising the odour-causing molecules in the air. Place activated charcoal filters in your exhaust air system to ensure that all escaping odours are filtered out.
Geruchsneutralisatoren There are various products on the market that have been specially developed to neutralise odours. These can be used in combination with your ventilation system to further minimise odour. Products such as ONA gel or odour-neutralising sprays can be helpful.
Plants for odour reduction Certain plants can also help mask the odour of cannabis. Plants such as lavender, rosemary and mint have strong scents of their own that can mask the odour of cannabis. These plants can be strategically placed in and around the greenhouse.
Regular cleaning Keep your greenhouse clean and free of dead leaves and plant debris, which can also contribute to the odour. Regular cleaning prevents the accumulation of organic material that can rot and increase the odour.
Humidifiers and ozone generators These devices can also contribute to odour control. A humidifier keeps the humidity at an optimum level, while an ozone generator breaks down odour molecules. However, both devices should be used with caution, as they can harm plants and people if used incorrectly.
Airtight storage If you store harvested cannabis in the greenhouse, make sure it is stored in airtight containers. This will prevent the odour from escaping and spreading throughout the greenhouse.

By combining these measures, you can effectively manage odour problems when growing cannabis in a greenhouse. Good odour control not only ensures a more pleasant environment, but also helps to avoid unwanted attention.

Cannabis in the outdoor greenhouse

Outdoor greenhouses for growing cannabis in the garden

Growing cannabis in an outdoor greenhouse offers many benefits and can be an ideal solution for growers who want to combine the natural benefits of outdoor growing with the added protection of a greenhouse. An outdoor greenhouse in the garden provides a controlled environment that offers plants protection from extreme weather conditions and pests, while allowing them to make the most of natural sunlight and fresh air.

Choosing the right location for your outdoor greenhouse is crucial. It should be in a place that receives plenty of sunlight throughout the day and is well protected from strong winds. The soil should be well-drained to avoid waterlogging, which could cause root rot. If the soil in your garden is not ideal, you can use raised beds or large planters to create optimal conditions.

An outdoor greenhouse can be built from a variety of materials. Glass and polycarbonate greenhouses are particularly popular as they are robust and durable. Foil greenhouses are a cheaper option and easy to install, but may not offer the same protection and insulation as their sturdier counterparts.

Advantages and disadvantages of outdoor greenhouse cultivation

Growing cannabis in an outdoor greenhouse has its own pros and cons that you should consider before deciding on this method.

Advantages:

Natural light source: The outdoor greenhouse utilises natural sunlight, which is ideal for growing cannabis. Sunlight is free and provides the full spectrum of light that plants need.
Protection from the weather: A greenhouse protects the plants from extreme weather conditions such as heavy rain, hail or frost. This can be particularly advantageous in regions with unpredictable weather.
Extended growing season: Similar to an indoor greenhouse, an outdoor greenhouse allows you to extend the growing season. You can start earlier in the year and harvest later in the autumn.
Protection against pests: A well-constructed greenhouse can keep out many pests that could be a problem in outdoor cultivation. This reduces the need for pesticides and promotes more natural cultivation.
Better control over the environment: Although it is an outdoor greenhouse, you still have some control over temperature and humidity, which reduces the risk of plant diseases and mould growth.

Disadvantages:

Higher initial costs: Building an outdoor greenhouse can be more expensive than simply growing outdoors. The costs for materials, construction and any necessary permits should be taken into account.
Regular maintenance: A greenhouse requires regular maintenance to ensure that it remains in good condition. This includes cleaning the walls, checking for cracks or damage and maintaining the ventilation systems.
Energieverbrauch: If you use additional lighting or heating in your greenhouse, energy costs may increase. This should be taken into account when planning your cultivation.
Room boundaries: Depending on the size of your garden, the space for a greenhouse may be limited. A greenhouse that is too small can restrict the growth of plants.
Visibility and safety: A greenhouse can be visible in the garden and may attract unwanted attention. Security measures, such as a lockable greenhouse, should be considered.

By weighing up these pros and cons, you can decide whether an outdoor greenhouse is the right choice for your cannabis grow. However, with the right planning and care, you can reap the many benefits and achieve a successful harvest.

When to grow cannabis in a greenhouse?

Best time for growing

The right time to grow cannabis in a greenhouse is crucial to ensure a healthy and productive harvest. In general, cultivation can start in early spring as soon as the days get longer and temperatures rise. The advantage of a greenhouse is that you can start earlier, regardless of the weather conditions outside.

In most regions, this means that you can start germinating your seeds from March or April. Germination is best done in small pots or growing cubes that are placed in a warm and humid environment. A heated growing bed or heat mats can be very helpful here to ensure an even temperature and promote germination.

As soon as the seedlings are strong enough and the danger of frost has passed, they can be transplanted into larger pots or directly into the greenhouse soil. Make sure to gradually acclimatise the young plants to the stronger sunlight and lower night temperatures to avoid stress.

Extending the season with the greenhouse

A major advantage of growing cannabis in a greenhouse is the ability to extend the growing season. While traditional outdoor cultivation is heavily dependent on the seasons, you can grow in a greenhouse almost all year round.

In spring, the greenhouse enables an earlier start as the plants are protected from cold and frost. You can start growing before the outside temperatures consistently rise above 10°C. The greenhouse retains the heat and creates an ideal microclimate for the growth of your plants.

In autumn, on the other hand, you can delay the harvest time. While the outside temperatures drop and the days get shorter, it remains warm enough in the greenhouse to support the growth of the plants. Heaters or frost protection lamps can help to keep temperatures at an optimum level.

This extended growing season gives you the opportunity to achieve several harvests per year. Especially when using autoflowering varieties, which flower independently of the light cycle, you can continuously grow and harvest new plants.

By taking advantage of a greenhouse, you not only maximise your yields, but you can also grow a greater variety of strains. This gives you the flexibility to try out different cannabis strains and optimise your growing methods.

Cannabis in a mini-greenhouse

Advantages and challenges

Growing cannabis in a mini-greenhouse offers a number of advantages, but also comes with some challenges. A mini-greenhouse is ideal for growers with limited space, for example on a balcony, terrace or in a small garden.

Advantages:

Platzsparend: Mini greenhouses take up very little space and are therefore perfect for urban environments or small gardens.
Kostenersparnis: They are generally cheaper to buy and maintain than large greenhouses.
Easy handling: Due to their size, they are easier to install and maintain. In addition, monitoring the environmental conditions is easier and quicker.
Diskretion: Mini greenhouses can be placed inconspicuously in urban or populated areas, providing more privacy.
Mobilität: Smaller greenhouses are often portable and can be easily moved as required.

Challenges:

Limited space: The limited space can restrict the growth of plants and requires careful planning in order to utilise the space efficiently.
Temperaturkontrolle: Due to their small size, mini-greenhouses can heat up or cool down more quickly, which requires careful monitoring of the temperature.
Luftzirkulation: Good air circulation is more difficult to achieve in small greenhouses, which increases the risk of mould and pests.
Fewer plants: Due to the limited space available, fewer plants can be grown, which limits crop yields.

Tips for growing in small greenhouses

To get the most out of your mini-greenhouse, there are some tips and tricks that can help you grow cannabis successfully:

Optimum use of space: Utilise the available space efficiently by using vertical growing techniques. Hanging racks or plant stands can help maximise vertical space.
Choose compact varieties: Opt for compact cannabis strains or autoflowering varieties that remain smaller and require less space. These varieties are ideal for growing in confined spaces.
Temperature and humidity control: Invest in a thermometer and a hygrometer to keep an eye on the temperature and humidity. Air vents or small fans can help improve air circulation and ensure stable conditions.
Beleuchtung: Additional lighting may also be necessary in a mini-greenhouse. LED lamps are energy-efficient and generate less heat, which is an advantage in small rooms. Make sure that the lighting is evenly distributed.
Regular maintenance: Due to the limited space, regular care is particularly important. Prune your plants regularly to control growth and ensure good air circulation.
Automated systems: Consider installing automatic irrigation and aeration systems. These systems can significantly reduce the amount of care required and provide constantly optimal growing conditions.
Diskretion: If discretion is important, make sure your mini-greenhouse is well hidden or in a low-visibility corner. Odour filters and neutralisers can help to minimise the characteristic cannabis smell.

By following these tips, you can grow healthy, high-yielding cannabis plants in a mini-greenhouse. Despite its limited size, a mini-greenhouse offers many opportunities to get creative and make the most of your limited space.

Drying cannabis in a greenhouse

Ideal drying conditions

Drying cannabis is a crucial step in ensuring the quality and potency of the harvest. After harvesting, the Flowers must be dried slowly and evenly to preserve the full flavour and active ingredients. Ideal drying conditions are important to prevent mould growth and ensure the best possible quality.

The ideal drying conditions for cannabis are a temperature of 18-24°C and a relative humidity of 45-55%. These conditions allow the Flowers to dry slowly and evenly without drying out too quickly and becoming brittle.

A dark, well-ventilated room is ideal for drying. The greenhouse can serve as such a room if it is equipped accordingly. Blackout films or curtains can be used to reduce the light, as light can break down the sensitive cannabinoids and terpenes in the Flowers.

Air circulation is another important factor. Stagnant air can lead to moisture build-up and mould growth. Fans that gently move the air help to distribute moisture evenly and prevent the formation of mould. However, it is important that the air is not blown directly onto the Flowers as this can cause it to dry too quickly.

Prevention of mould and loss of quality

Some additional measures are required to prevent mould growth and loss of quality:

Regular check: Check the Flowers regularly during the drying process for signs of mould or excessive drying out. Remove affected areas immediately to prevent the mould from spreading.
Luftfeuchtigkeitskontrolle: Use a hygrometer to monitor the humidity in the drying room. If necessary, a dehumidifier can be used to keep the humidity at an optimum level. Alternatively, a humidifier can be used if the air is too dry.
Correct suspension: Hang the Flowers in a well-ventilated area so that they are not too close together. This allows better air circulation and prevents the accumulation of moisture.
Avoidance of contact: Touch the Flowers as little as possible during the drying process so as not to damage the trichomes (the resin crystals on the Flowers). The trichomes contain most of the active ingredients and flavours that you want to preserve.
Slow drying: Drying should be done slowly, ideally over a period of 7-14 days. Drying too quickly can lead to a loss of flavour and potency, while drying too slowly increases the risk of mould growth.
After drying: Once the Flowers are dry, they should be stored in airtight containers at a relative humidity of 58-62%. A curing process of at least two weeks can further enhance the flavours and maximise potency.

By following these drying techniques, you can ensure that your cannabis flowers develop their full potential. Careful drying is crucial to avoid mould and preserve the quality of your cannabis. With the right preparation and care, you can achieve a first-class harvest that impresses in terms of both potency and flavour.

Tomatoes and cannabis in the greenhouse

Similarities and differences in cultivation

Growing tomatoes and cannabis in a greenhouse can be an interesting and beneficial combination. Both plants have similar requirements, but there are also some differences that need to be considered.

Similarities:

Lichtbedarf: Both tomatoes and cannabis need plenty of light to grow optimally. A greenhouse offers the opportunity to meet this need through natural sunlight and, if necessary, additional lighting.
Temperatur: Both plants thrive best at similar temperatures. During the day they prefer temperatures between 20-28°C and at night between 15-20°C.
Luftzirkulation: Good air circulation is important for both plants to prevent mould and disease. Fans in the greenhouse can help to keep the air moving.
Bewässerung: Tomatoes and cannabis require regular but not excessive watering. The soil should be moist, but not wet, to avoid root rot.
Nährstoffe: Both plants benefit from a balanced supply of nutrients. Organic fertilisers are ideal for promoting soil life and keeping plants healthy.

Unterschiede:

Wachstumszyklus: Cannabis has a clear growth and flowering cycle, depending on the variety, whereas tomatoes can produce fruit continuously Flowers. Adapting the light cycles in the greenhouse can be a challenge.
Platzbedarf: Cannabis can grow very large, depending on the variety and growth phase, while tomatoes usually remain more compact. Careful planning and positioning in the greenhouse are necessary to ensure that both plants have enough space.
Schädlingsbefall: Whilst cannabis and tomatoes can have similar pests, the specific susceptibilities can vary. Regular inspections and good care are necessary to recognise and treat problems early.

Advantages of mixed cultivation

Growing tomatoes and cannabis together in a greenhouse can offer several advantages:

Optimum utilisation of space: By combining the two plants, you can utilise the available space in the greenhouse more efficiently. Tomatoes, for example, can grow along the sides or on climbing supports, while cannabis has more space in the centre for vertical growth.
Natural pest control: Certain tomato varieties can help keep away pests that could also infest cannabis. Conversely, the terpenes and essential oils of cannabis can deter pests that infest tomatoes.
Diversifizierung: By diversifying your greenhouse, you reduce the risk of crop failure due to pests or diseases that favour a particular plant species. A mixed crop can lead to a more stable and healthier ecosystem.
Improved soil quality: The different root systems of tomatoes and cannabis can penetrate and improve the soil in different ways. This leads to better soil drainage and a balanced distribution of nutrients.
Increasing crop diversity: With a mixed crop, you can not only enjoy a greater variety of plants, but also extend the harvest period. While tomatoes bear fruit continuously, you can harvest cannabis several times a year, especially if you grow autoflowering varieties.
Aesthetic and practical advantages: A greenhouse with mixed cultivation not only looks more attractive, but also offers practical advantages. The different heights and growth forms of the plants can make optimum use of the available light and air space.

By growing tomatoes and cannabis together in a greenhouse, you can utilise the benefits of both plant species and create a healthier, more productive growing system. With the right planning and care, you can successfully establish a mixed crop that is both ecologically sound and high-yielding.

Fazit

The Growing cannabis in a greenhouse offers numerous advantages that make it an attractive option for growers. From better control over environmental conditions to the ability to extend the growing season, a greenhouse allows for an optimal growing environment for your plants. With protection from extreme weather conditions and pests, you can achieve healthier and higher yielding plants.

Careful selection of the right equipment - from the right greenhouse and additional lighting to efficient ventilation and irrigation systems - is crucial to the success of your cultivation. By choosing suitable cannabis strains and paying attention to soil preparation and fertilisation, you lay the foundation for a successful harvest.

Dealing with Geruchsproblemen and the correct drying of the harvest are important aspects that you should not neglect. With the right measures for odour control and optimal drying conditions, you can ensure the quality and potency of your cannabis flowers and prevent mould growth.

For growers with limited space, the Mini-Gewächshaus a flexible and efficient solution. Despite the challenges of limited space, healthy and high-yielding cannabis plants can thrive even in small greenhouses through clever utilisation and careful care.

The combination of Cannabis and tomatoes in the greenhouse offers interesting opportunities for mixed cultivation. By utilising the different growth needs and advantages of both plants, you can not only increase crop diversity, but also improve soil quality and promote natural pest control.

Overall, the Growing cannabis in a greenhouse is a worthwhile investment that offers many advantages for both beginners and experienced growers. With the right planning, equipment and care, you can optimally control the conditions and achieve high-quality yields. Whether you're growing as a hobby or aiming for larger-scale production, a greenhouse gives you the control and security you need to be successful.

Happy growing!

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Fachautor und Biochemier Niklas Bergmann

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.