Choosing cannabis strains for an indoor grow can sometimes be a time-consuming process that requires a lot of research in order to weigh off between different features like flowering time, yields per m², effects, and flavours. Most growers will also base their decision on the personal experience they made with certain varieties over the years. However, there’s a point in the life of every grower when the decision to choose a certain strain over another is tough, and the extensive product range Royal Queen Seeds doesn’t necessarily make such decisions easier. That’s why we decided to put together a Top 5 for indoor growing, to give you a few ideas on strains that show excellent results in the controlled environment of an indoor grow room or tent. Every single grower has good reasons for choosing exactly the strain he does, and there are just too many strains from our catalogue that have the potential to show up in this Top 5. Think of the following strains as a small selection of our varieties for indoor growing.


We like to think of our Critical as the perfect all-rounder and recommend it to outdoor growers, novices, and anyone aiming for extremely high yields in a short flowering period. Indoor growers can profit from a huge production that exceeds indoor yields of 600g/m² in some cases, a strong narcotic stone due to average THC levels of 18%, and a highly stable genetic background consisting of Afghani and Skunk genetics. What makes this strain one of the best choices for an indoor grow? Well, no other variety from the Royal Queen Seeds product range is capable of yielding higher in a short flowering period of 7-8 weeks. If you’re looking for a vigorous and resilient strain that won’t cause any trouble other than confronting you with large amounts of high-quality cannabis - Critical is your choice.

Critical Indoor


Critical Royal Queen Seeds

Genetic background Afghani x Skunk
Yield indoor 500 - 550 g/m2
Height indoor 80 - 140 cm
Flowering time 7 - 8 weeks
THC strength THC: 18% (aprox.) / CBD: Low
Blend 40% Sativa, 60% Indica
Yield outdoor 500 - 550 g/per plant (dried)
Height outdoor 180 - 220 cm
Harvest time Late September
Effect Stoned, physically and mentally

Buy Critical


The Royal AK originates from a cross of between several Columbian, Mexican, Thai, and Afghan landraces. Besides the Afghan influence, it’s a strain that’s greatly influenced by three different Sativa strains from different corners of the world. This unique genetic blend enabled countless indoor growers since the early 90’s to produce high yields of extremely resinous buds that provide uplifting, creativity-enhancing effects in combination with powerful body stone. It was one of the first strains that exceeded 20% of THC and won multiple Cannabis Cups in the 90’s. Why choose Royal AK for an indoor grow? It offers a high calyx to leaf ratio, solid side branches to maximize yields using LST methods, and fruity Sativa flavours with hints of pine and petroleum.

Royal AK

Royal AK

Royal AK

Genetic background Columbian, Mexican, Thai & Afghan Columbian, Mexican, Thai & Afghan
Yield indoor 525 - 575 gr/m2
Height indoor 80 - 140 cm
Flowering time 8 - 9 weeks
THC strength THC: 19% (aprox.) / CBD: Medium
Blend 60% Sativa, 40% Indica, 0% Ruderalis
Yield outdoor 600 - 650 g/per plant (dried)
Height outdoor 130 - 170 cm
Harvest time Early October
Effect A combination of stoned + high

Buy Royal AK



The previous strains, Critical, and Royal AK are well-established varieties and cultivated by many indoor growers across Europe for many years. Widespread popularity is often a good sign indicating the quality of a certain strain or lineage, but sometimes it’s beneficial to give new genetics a chance - a reason why we decided to list our newly developed Royal Cookies in this Top 5. This strain is based on the notorious Girl Scout Cookies “Forum cut”, an elite clone that was only available in a cannabis internet forum. Girl Scout Cookies is one of the most potent strains one could purchase in US dispensaries in recent times. Today, Royal Queen Seeds offers a stabilized seed of this Californian classic with outrageous THC levels of 23% - the highest THC content of all our strains.

Indoor Cookies

Royal Cookies

Royal Cookies

Genetic background Cookies Forum x Cookies Forum
Yield indoor 450 - 525 gr/m2
Height indoor 80 - 110 cm
Flowering time 8 - 9 weeks
THC strength THC: 23% (aprox.) / CBD: Low
Blend 20% Sativa, 80% Indica, 0% Ruderalis
Yield outdoor 650 - 700 g/per plant (dried)
Height outdoor 175 - 210 cm
Harvest time Middle of October
Effect Relaxed and Euphoric

Buy Royal Cookies



Royal Moby is a very good option for indoor growers who prefer to grow a smaller number of plants, maybe just one or two, to achieve high yields per plant using low-stress training methods. Growing Moby Dick in a sea of green is just as possible and results in high yields of up to 600g/m² but a ScrOG could potentially take advantage of the many strong side branches and produce the same results by growing a limited number of plants. Indoor growers need to compromise a bit on space but will grow plants that yield excellent and produce high THC levels of 21%. Royal Moby handles large amounts of fertilizers without being overfed to soon and is therefore also a viable option for growers using hydro set-ups like DWC. The high of Royal Moby is too strong to sell it without additional warnings – enjoy responsibly and don’t operate heavy machinery while being under the influence of this gigantic high.

Indoor Moby

Royal Moby

Royal Moby Royal Queen Seeds

Genetic background Haze x White Widow
Yield indoor 500 - 550 g/m2
Height indoor 80 - 140 cm
Flowering time 9 - 10 weeks
THC strength THC: 21% (aprox.) / CBD: Low
Blend 65% Sativa, 35% Indica
Yield outdoor 500 - 550 g/per plant (dried)
Height outdoor 200 - 300 cm
Harvest time Late October
Effect A combination of stoned + high

Buy Royal Moby


We had no other option than to list this incredibly potent Haze strain in our Top 5 for indoor growing. It’s simply one of the best varieties of our entire product range, and we can recommend it to anyone with a little experience in cannabis cultivation and the willingness to practice patience for 10-11 weeks of flowering. Waiting a few additional weeks compared to other strains doesn’t come without tremendous benefits regarding potency, flavours, and effects. Our Amnesia Haze gets regularly tested at 22% THC, combines haze freshness with fruity flavours, and its powerful effects resemble a parabolic flight into the stratosphere – you’ll experience a rush of euphoria together with a strong, uplifting head high that promotes a feeling of zero gravity.

Amnesia Indoor

Amnesia Haze

Amnesia Haze

Genetic background Original Amnesia Haze
Yield indoor 600 - 650 gr/m2
Height indoor 80 - 140 cm
Flowering time 10 - 11 weeks
THC strength THC: 22% (aprox.) / CBD: Medium
Blend 70% Sativa, 30% Indica, 0% Ruderalis
Yield outdoor 650 - 700 g/per plant (dried)
Height outdoor 175 - 210 cm
Harvest time Late October
Effect Extremely high, long-lasting, body relaxing

Buy Amnesia Haze


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