If you’re planning on growing cannabis strains in a greenhouse, congratulations – you’ve made a great decision! Greenhouse cultivation offers many advantages, including stealth, cost reduction, year-round harvests, and protection from the elements in all climates.
If you’re wondering which seeds to choose for your greenhouse project, there are a few factors to consider. Before we get to the recommendations, let’s consider some things to keep in mind when selecting the best strains for a greenhouse project.
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Photoperiod Strains in a Greenhouse
Photoperiod strains rely on light to support the vegetative stage and stimulate the flowering stage. If you’re depending on natural light to grow your plants, this limits your options for growing cannabis year-round due to the variation in daylight hours from season to season. You can undoubtedly supplement natural sunlight by adding artificial lighting to your greenhouse. This means having to light-proof your greenhouse to avoid natural light impeding your artificial light schedule and causing issues with plant development. Obviously, this also involves incurring some costs in terms of equipment and energy use.
Photoperiod strains in a greenhouse will also likely require you to employ plant-training techniques to keep their growth from getting out of control. Sunlight will initiate the kind of stretching in many plants that needs topping, scrogging and other methods to limit the amount of space taken up by the impressive growth spurts. Depending on the size of your greenhouse, you may be kept busy.
Autoflowering Strains in a Greenhouse
Autoflowering strains are arguably the best choice for growing in a greenhouse – although your budget, space and level of experience may dictate otherwise. There are several reasons why autoflowering plants are well-suited to greenhouse cultivation:
These strains don’t rely on a set or strict light schedule to vegetate and flower, meaning you can plant and harvest these at any term of year – a definite advantage over photoperiod strains.
They’re far less likely to suffer harm or diminished yields due to variations in sunlight hours received.
Autoflowers are naturally smaller, meaning you can plant more of them to offset the naturally lower yields without worrying about them taking those huge stretches that eat up greenhouse space and require the busy hands-on work of training techniques. If you’re new to greenhouse growing and want to maximise output, read more about the Sea of Green technique to learn how you can make the most of your space.
Without further ado, let’s take a look at Seedsman’s recommendations of the best cannabis strains in a greenhouse grow.
A top pick for any situation due to its high yield and irresistible taste, Zkittlez Auto has plenty to offer for greenhouse cultivators. It’s a short plant that is unlikely to exceed 120cm and provides a good degree of stealth for those with neighbours to worry about – but the small stature doesn’t translate to disappointing yields.
Zkittlez Auto is good for a whopping 800g/m2 when grown outdoors, and those buds positively bling with trichomes. She’s a highly vigorous one, too, and can take in a high level of nutrients. Greenhouse growers should note that Zkittlez Auto has tremendous lateral branching, so the use of supports or ties are recommended to limit the risk of snapping.
The THC content of Zkittlez Auto is very high, with as much as 25% offered by this impressive strain. As far as effect goes, Zkittlez Auto’s mostly-sativa nature means a happy, chatty, uplifting sensation is headed your way – once your mouth stops watering from the taste. This is one of the sweetest strains around and offers copious amounts of fruit, candy and berry flavours for s smooth, delicious smoke.
In terms of sheer bang for the buck, you’ll be hard-pushed to outdo Peyote Wi-Fi. She’s a significantly bigger plant due to her photoperiod nature, but what you may forfeit in terms of stealth, you more than make up for the yield’s size. Fancy harvesting a frankly staggering 1500g/m2 from your greenhouse plants? If you do, these are the seeds to go for.
There’s a longer flowering time with Peyote Wi-Fi, but there’s no doubt that the payoff is worth the wait. A mostly-indica variety with big, broad leaves, this strain has the kind of sugar-frosted appearance that cannasseurs love to see – and with a very high THC content (26%!), they’ll love to smoke it even more.
Peyote Wi-Fi’s unique taste profile blends sour lemon and lime flavours with Diesel notes. The effect is powerful, with strong relaxing properties coming from its indica dominance. One of the best strains to grow in a greenhouse.
Get used to seeing Blue Dream appearing in all manner of top 10 lists – this popular strain has ‘elite’ written all over it. This beauty walks into our recommendations with ease, ticking all the big boxes with aplomb.
Blue Dream presents no particular growing problems but is said to have excellent resistance, making her among the ideal strains for greenhouse growing. This is a medium-sized plant that grows to around 350cm after a flowering time of about ten weeks. After that, you’ll find yourself yielding up to 850g/plant of gorgeous, big, dense buds with resin to the fore.
Crossing Blueberry with a Haze gives Blue Dream its stunning palette of flavours – fruity, berry, lemon, and citrus notes provide a sharp, appealing taste profile which is then offset by a slightly spicy, herbal bite. THC levels are high, around 20%, and the mostly-sativa nature assures a powerful, positive, uplifting effect that will have you flying in a Blue Dream in no time. This strain is recommended for its therapeutic effects and is often touted for its alleviative properties for conditions including anxiety, depression, nausea, stress, and pain and inflammation.
Northern Lights Auto
If you’re looking for the reassurance of a strain with excellent survival skills, look no further than Northern Lights Auto – this is one of our most resilient varieties, almost tailor-made for greenhouse or outdoor cultivation.
Crossing Northern Lights with a Ruderalis produced this highly-reliable plant, and it positively thrives in greenhouse environments.
Another small plant, this squat indica-dominant hybrid, won’t grow much more than 90cm, flowering in 9 weeks and yielding in the 200g/plant region. Remember, the Sea of Green planting technique can help you offset slightly smaller yields by allowing you to install multiple smaller plants.
Many breeders and seedbanks have selected Northern Lights for its high THC levels and excellent resistance to pests and mildew. This OG is a legendary cannabis strain first produced in the Netherlands. This OG is a perfect strain to grow in a greenhouse.
White Widow is one of the best-known and still one of the most potent, cannabis strains globally. Initially created in the early 1990s, its release to the coffee shops of Amsterdam was met with universal rave reviews as canna-tourists flocked in their thousands to find out whether all the advance publicity for this white strain was true. It was and remains so today. Bred by crossing a Brazilian sativa strain with a highly resinous South Indian indica, it is named after the plant’s frosty appearance, making it white with resin.
It is an easy strain to grow almost anywhere; its eight-week flowering period ensures that it will be ready to harvest sooner than many of its peers and thrives in a greenhouse environment. THC levels are high, around 20%. Weed strains don’t come much more recommended.
White Widow is designed for the utmost potency rather than any complex flavour profile, although the smoke is very smooth and satisfying. The initial hit comes on fast and strong, leaving anyone but the most experienced canna-seur to sit down. This slowly evolves into a very relaxing high ideal for enjoying music.
Alaskan Purple Auto
To provide something for everyone, we present Seedsman’s own Alaskan Purple Auto. If you’re looking for a strain with a relaxing effect, this one does the job while ticking plenty of other boxes along the way. Alaskan Purple Auto offers the best of both worlds thanks to a high THC content of around 18%, nicely balanced with its 1.6% CBD content.
Greenhouse growers will find this a useful strain due to its respectable height – sneaking in at around 90cm, Alaskan Purple Auto will be a furtive friend with a low profile in the garden. Yields are large for an auto, at 400-500g/plant, and the size of these plants allows you to assemble more in your confined space. A cross between Alaskan Purple and a Ruderalis with high resistance to pests, Alaskan Purple Auto is a perfect strain to grow in a greenhouse project.
With a sweet, earthy flavour, Alaskan Purple Auto is a real treat, and the indica-dominant nature of this strain results in a powerful effect that soothes both head and body in a perfect balance. Flowering in just eight weeks, this is an excellent pick for greenhouse projects.
More experienced cultivators know that the best things come to those who wait, and CandyLand from Garden of Green slots into that category with style. It’s a high THC, high-yielding strain that requires the use of training techniques to control – so it’s not suited to newbies, but the pay-off is undoubtedly worth the extra efforts.
With a colossal THC content of around 24%, CandyLand could knock novice smokers for six, but stick with it. You’ll find a supremely euphoric buzz that stimulates creativity and carries strong cerebral effects. Better yet, this strain has robust therapeutic potential.
The scent is sweet and juicy with a similar taste profile. THC can reach 29% with just 1% CBD. The effect is that of a warm, cosseted sensation together with motivational energy that will allow the pursuit of a variety of tasks.
CBG Relief Auto
CBG Relief Auto Feminised is a new auto-flowering strain that is rich in CBG (cannabigerol) while producing virtually zero THC. Production of CBD is similarly extremely low at less than 0.09%.
Cannabigerol (CBG) has been generating a lot of interest lately regarding its medicinal potential. However, research into this particular cannabinoid is ongoing, so that no specific claims can be made yet.
Seedsman CBG Relief Auto is 60% sativa and grows into medium-size plants with commensurate yields. It is a fast-maturing strain that is ready to be harvested in 8 – 9 weeks from seed. Compact flower formations are adorned by a profusion of bright, sparkling trichomes and have a light floral scent and taste.
CBG levels are high at just over 7%, which compares very favourably with the more usual 1% from other types of cannabis. Its effect is completely non-psychoactive but acts as a body relaxant. The quantity of resin produced makes it an attractive choice from which to make CBG-rich extracts.
Purple Punch is a 90% indica hybrid strain that was bred by crossing Granddaddy Purple with the famous San Fernando Valley (SFV) OG Kush. Yields are excellent indeed from a strain that is so easy to grow that even the absolute beginner should have no problems obtaining a great crop.
This strain’s relatively early finish means that it is an excellent choice for greenhouse cultivation. With strong resistance to all kinds of mould, the cold and even spider mite, environmental problems cause little trouble for Purple Punch. It tolerates cool, temperate and hot climates. It’s a short and stocky plant with multi-branching growing to a height between 90cm-150cm.
The scent of Purple Punch is reminiscent of the interior of a good quality bakery. Its taste is that of apple pie with cloves.
If you’re looking for a strain that provides a hard-hitting high and massive yields, your search is over – Trainwreck Auto from Atlas Seed delivers both properties in spades.
If you’re growing her in a greenhouse, you’ll soon be rubbing your hands together in anticipation of her outstanding output since the additional light and humidity translate to yields as high as 800 g/plant.
She has a life cycle of 75 – 90 days, allowing more than one crop per year in regions with longer growing seasons. When fully mature, the lime green buds are dense and very sticky with resin that produces a sweet, sappy scent. Yields are excellent indeed, especially for an auto-flowering strain.
When the buds have been dried and cured, the scent remains sweet with an added terpentine note due to the presence of terpinolene, a known anti-microbial agent that possesses powerful tranquilising properties.