One of our recent articles talked about the fact that there’s no safe, guaranteed way to make your marijuana plants finish bloom phase faster than their genetics program them to do and still get maximum harvest weight and potency.

We revealed that some products sold in grow stores that claim to be bloom phase accelerators, bud hardeners, bud bulkers and vertical height limiters contain dangerous chemicals including plant growth regulators. Others contain only toxic overdoses of phosphorus and potassium. These products don’t work, harm your plants, and are a waste of money.

If you want fast marijuana crops, you need to buy fast marijuana strains, and this article gives you insider information on the fastest marijuana strains we’re sure will produce heavy harvests of potent buds.

Here are the most reliable, true-breeding, consistent, potent and heavy-yielding cannabis strains out of the hundreds we’ve grown:

Biddy Early by Serious Seeds: This strain is almost like a photoperiod autoflowering strain, because it starts developing pre-flowers very early, especially if you’re growing outdoors.

Simon, the founder of Serious Seeds, says the strain was developed in collaboration with Magus Genetics as a primarily outdoor strain that would be hardy enough and finish fast enough to generate great results in Holland’s short summer season. Serious Seeds is one of the original Dutch cannabis seeds companies, famous for AK-47, Bubblegum and other High Times Cannabis Cup winners.

Biddy Early is great outdoors in cool rainy climates, especially because it resists gray mold. It’s also a top performer indoors, but you want to run your grow room a little cooler than usual and only give your plants 2-4 weeks from seed in grow phase before flipping the lights to trigger bloom phase, but I emphasize that your plants have to have at least a moderately-developed root system and at least five sets of true leaves before you put them into bloom phase.

This strain includes pure Afghan Skunk genetics, and it smells like it. Because Thai, Colombian and Mexican Sativa genetics have been added in, it often grows out as only one Sativa phenotype producing a high and bud structure more Sativa than Afghani or Indica. A second, less-prevalent pheno leans more Indica, but still provides a stimulating rather than couchlock high.

Outdoors, Biddy Early often finishes before October. Indoors it needs 50-60 days in bloom phase. This strain is easy to grow, relatively short in stature, and useful for beginner growers.

Sour 60, from New420Guy Seeds: This autoflowering strain combines Lowryder x Master Kush x Blueberry x Sour Bubble to give you an auto-flowering hybrid ready for harvest 60-70 days after germination.

This strain loves 20 hours of light per day and grows well indoors or outdoors, as long as it gets enough direct light. No need for topping or training. The strain offers two phenotypes. One produces a huge main cola and few side branches. The other goes blue-purple and produces a dense plant full of main colas.

Sunset Sherbet, from New420Guy Seeds is a photoperiod hybrid of Girl Scout Cookies and Pink Panties, which is said to be derived from Blackberry Kush. Although the genetic mix is heavy on Indica, you still get Sativa effects.

Sunset Sherbet gives you large, fat, colorful buds and a strong scent with notes of orange, skunk, and berries. The strain has a creeper high, so wait a little longer than usual before inhaling more, as you can easily end up paralyzed on your couch if you use too much.

Bloom phase duration is 56-61 days.

The same breeder also offers photoperiod Wedding Cake, also known as Pink Cookies or Birthday Cake, which is a unique cross between a Sour Cherry Pie and Girl Scout Cookies. Phenotype variations affect the dessert taste of this strain, ranging from sour and citrus to sweet vanilla.

You only need 56-63 days in bloom phase to get very potent, fat buds with THC levels as high as 25%, and a high that tends towards sedation more than stimulation. If you suffer from insomnia, anxiety or chronic pain, this strain’s for you.

Auto Blackberry Kush, from Dutch Passion: Dutch Passion is one of few legendary Dutch cannabis seeds companies still producing great new strains and maintaining the quality and reliability of its heritage strains. Their founder helped pioneer the development of autoflowering marijuana.

Auto Blackberry Kush is an Indica-dominant combination of heritage Blueberry and Hashplant. It grows out into short, stocky, resilient plants with a huge main cola, fruity-Kushy odor, and a heavy Indica high. We’ve harvested 62 days after germination, but some phenotypes need 70-80 days from germination to harvest—still very fast. The photo for this article shows you how high-yielding Auto Blackberry Kush can be!

Dutch Passion offers a photoperiod strain that has an incredibly fast bloom phase. Its Bubba Island Kush feminized seeds come from crossing Granddaddy Purple with OG Kush. You get hardy plants that produce extremely resinous buds and deep-hued bluish-purple leaves. The buds are so resinous that this strain is a favorite of growers who make dry sift, bubblehash, shatter and other cannabis extracts.

Bloom phase can be as short as 48 days, but the average bloom phase duration is 50-57 days, making this one of the fastest high-yielding, high-THC photoperiod strains ever.

Dr. Acula, from Nerds Genetics: You’ve probably never heard of this American cannabis seeds company, but it’s much better than most of the ones you have heard of!

Their Dr. Acula is a complex photoperiod strain that produces fat buds that have equivalent amounts of THC and CBD. Genetic influences include Harlequin, Chem Dawg, Sour Diesel, and Colombian Gold. Bloom phase is 48-58 days.

Although Dr. Acula is high-CBD and a great medicine, it’s also recreational. The high is surprisingly pleasing and strong, and yields of berry-sour buds are heavy. The strain is especially resilient and can handle outdoor and indoor growing conditions.

Lemongrass, from Humboldt Seed Company: We’ve written before about Humboldt Seed Company, a highly-respected cannabis seeds breeding family business from Northern California’s famed Emerald Triangle. HSC is known for its passionate, extensive phenotype hunts involving tens of thousands of plants, and its insistence on releasing only the best cannabis strains.

We’ve grown their photoperiod Lemongrass for several years and it has many rare qualities. Some phenotypes lean purple and are ready after only 50-55 days in bloom phase. Others are greener and more Sativa, and can take as long as 55-64 days in bloom phase.

Both phenotypes produce stunningly tasty, aromatic and stony buds with a rare combination high that can’t be described as either Indica or Sativa. Lemongrass has a deep genetic heritage including Lemon Kush, Humboldt Gelato, Lemon Haze, Skunk #1, Durban and Girl Scout Cookies.

If you look at its genetic heritage and assume it has an amazing lemony flavor and scent, you’re right.

The high from both phenotypes is extremely pleasant, balancing body effects with mental stimulation to produce a lovely euphoria with no hint of narcotic sedation or Sativa paranoia.

Lemongrass is very resilient, easy to grow, and moderately-high yielding.

Another of our favorite Humboldt Seed Company fast strains is photoperiod Dream Queen, with some phenotypes finishing after only 45-50 days in bloom phase. The strain combines Green Crack, Skunk #1, and a pure Afghani, but you don’t get an overwhelmingly sedative Indica high as you’d expect from a fast-finishing strain. Instead, the high is surprisingly stimulating, with a significant body stone.

These plants can get huge, considering how fast they finish, and the buds have a wonderful pine and orange smell and taste that hits you as soon as you open your storage container.

Please don’t confuse Humboldt Seed Company for Humboldt Seed Organization. Humboldt Seed Organization is a scam cannabis seeds company.

Think Fast, from Dutch Passion, is one of few commercially-available photoperiod marijuana strains produced by crossing an autoflowering marijuana plant with a photoperiod marijuana plant. Dutch Passion crossed their autoflowering Think Different strain with their famous, Cannabis Cup winner Power Plant photoperiod strain to produce Think Fast.

Dutch Passion told us that this unique cross was initially intended only as a breeding experiment, but Dutch Passion researchers discovered that the strain was extremely fast finishing, had no autoflowering traits, flowers early even before 12-12 bloom phase lighting, and gives you huge yields of potent buds in a 55-61 day bloom phase.

Even more surprising is that this strain is Sativa-dominant, making it one of the fastest-finishing, reliable photoperiod Sativa strains we’ve ever seen.

Pineapple Express #2, from G13 Labs: People argue about whether Pineapple Express marijuana was created before the hilarious Seth Rogen, James Franco, Danny McBride stoner movie of the same name. In the movie, the strain is portrayed a Sativa that produces hilariously stimulating highs.

G13’s version of Pineapple Express contains Trainwreck, Hawaiian, and Skunk #1 genetics. It can grow into a very large plant with high yields of Sativa-dominant light-green buds with the scent of pineapples, lemons and pepper. It’s easy to grow, and needs only 47-58 days in bloom phase.

The high isn’t as paranoid and hallucinatory as what you see in the Pineapple Express movie, but Pineapple Express #2 cannabis does produce a sweet, strong, stimulating high that you’ll love, and is great for parties.

Please refer to our previous article about attempting to accelerate bloom phase, and give these fast-finishing strains a try if you’re looking for rapid crop cycles that produce heavy harvests of high-potency marijuana.