Before the legendary cannabis-breeding company Serious Seeds unveiled a new strain called Serious Kush, they asked a trusted grower to try out four potential versions and assess the flavor, aroma, and potency of each. Our cultivation correspondent reports on the results.

A New Star Is Born

There’s no end in sight for the global phenomenon known as “Kushmania,” with new Kush-based strains and phenotypes popping out of the ground like mushrooms every month. But one variety stands out from the rest as a rare and precious specimen that deserves special attention. This new strain comes from Serious Seeds, the renowned and long-established seed company based in the Netherlands. The strain is called Serious Kush, and it consists of one of their classic best-sellers, White Russian, crossed with the legendary OG Kush.

While Serious Seeds have slightly stepped up the frequency with which they release new strains in recent years, they’re still laudably pursuing their strict quality-before-quantity policy, so the expectations for this new Kush variety were high. And according to Serious breeder Simon, their customers won’t be disappointed: “I’m personally very happy with the result of the Serious Kush. Also, many very experienced people who tried it remark to me that this version is, quote, ‘the best they’ve ever smoked’!”

Serious History

For well over two decades, Serious Seeds have been at the forefront of marijuana breeding. Founded in Amsterdam in 1995 by Simon, the company has won multiple Cannabis Cups and was one of the inaugural entrants in our High Times Seed Bank Hall of Fame back in 2007. While many other companies have expanded their line to include several dozen varieties or even more, Simon and his team have focused on just a handful of strains and kept them bred true, with superb flavor, scent and potency as well as impeccable germination rates.

The Serious stable of strains includes such stalwarts as AK-47, Kali Mist, Bubble Gum and White Russian. The seeds for these award-winning strains are produced in small batches and thus are always hand-selected and fresh. Simon’s emphasis on stability and consistency may have cost him a few dollars over the years, but the reputation he’s built for his products remains impeccable. That’s why we—and the rest of the world’s cannabis connoisseurs—have been so anxiously awaiting a new release from the Serious team.

Breeding Kush

Asked why he created Serious Kush, Simon said: “A few years ago, while I was on a trip to Canada, somebody gave me very resinous buds of an accidental cross between White Russian and OG Kush.” The potent strain quickly became a favorite among the people who tried it. “It was a great combo—a more subtle but clear and fuel-like ‘Kushy’ taste combined with the structure and yield of White Russian, which even after smoking for a long period doesn’t lose its strength and attractiveness. So I decided to start an actual breeding project back home with White Russian and OG Kush.”

The whole process for breeding Serious Kush took about a year and a half. After the initial selection stage for possible parents, Simon ended up with four different parent combos, from which a clear winner eventually emerged. As Simon notes, the keeper pheno offers a nice new blend of Kush’s trademark fuel aroma with the sweet and spicy undertones of White Russian. Serious Kush grows to a height of 75 to 85 centimeters when given four weeks of vegetative time, then requires 56 to 63 days in the flowering stage to mature, after which growers are rewarded with 300 to 450 grams per square meter.

Growing Seriously

It was with a good deal of excitement and pride that Mr. Power Planter approached the opportunity to become a part of this important new breeding project. This was at the crucial stage when Simon—still not sure which cross would ultimately prove to be the best—wanted to see those different parent lines grown out next to one another. As Simon reports, “By this time, we had plants of the same crosses growing at different locations, but Mr. PP was the first to offer a head-to-head comparison of those lines. So his work was very helpful to give us strong hints toward finding the favorite for which we were searching.”

For this test, Mr. Power Planter received four different White Russian x OG Kush lines in the form of 10 feminized seeds each. Although he knew these seeds were fresh and in optimum condition, he was stunned by the fact that every single one of them sprouted perfectly. A germination rate of 100% from 40 seeds is undoubtedly an impressive achievement. It turned out to be a great start!

After Mr. Power Planter had transplanted them into 7.5-liter pots, the plants grew beautifully in the vegetative stage. All of them displayed that typical Serious quality, defined by healthy, vigorous and compact growth on strong branches. In the veg stage, the four lines didn’t show much difference, apart from the fact that two were growing a bit more compactly—but aside from that, all of the plants resembled each other fairly closely, with similar or identical growth patterns and the same medium-broad, dark-green shade leaves.

Kush Flowers

“Simon seems to have done an excellent breeding job up to this point,” Mr. Power Planter noted, “as there already is a pretty good degree of vegetative uniformity, both within and among these four lines.” When he switched the 40 plants to the flowering stage after four weeks of veg growth, they were about 40 to 55 cm tall. Pre-flowering set in about a week later, with all of the plants exhibiting what Mr. Power Planter wanted to see: female flowers.

Stem elongation continued until week four of the flowering stage and naturally revealed a bit more dissimilarity between the lines due to somewhat different stretching behavior. This led to a couple of plants looking like dense indica bushes later on—albeit very well-branched indica bushes—while the others were taller and had a more open branching structure.

More differences became evident in terms of bud formation. While the buds overall were clearly on the indica side, some of them gradually differed in shape and calyx-to-leaf-ratio—no huge surprise when you have four different lines growing. But after eight weeks of flowering, all of the buds had three crucial things in common: They were all extremely big, extremely dense and extremely resinous!

As far as the eye could see, Mr. Power Planter’s sizable growroom was crowded with huge, fat head buds and heavily bud-laden side branches. “Now this is some really serious—even insane—overall quality!” he said enthusiastically. “When I heard that I would grow four different genetic lines from an intermediate stage of breeding, I had expected that only one or two would perform very well—but certainly not all of them to rock the show in such a stunning manner! Simply amazing … some of these plants are among the most resinous cannabis specimens I’ve ever witnessed. They’re so white that one gets almost blinded by the incredible abundance of resin that seems be to dripping out of the buds!”

Serious Scents

“The super-rich aroma of these plants is likewise impressive,” Mr. Power Planter continued. “Here we have a higher degree of variation as a matter of course, with two of the four lines basically giving off that typical Kush odor, sweetened with a sugary note of White Russian. I presume that these two lines will be shortlisted by Simon, as a ‘Kushy’ aroma certainly is an important selection criterion for him.”

The flowering times ran approximately eight to 10 weeks, with most of the plants maturing between weeks eight and nine. When Simon came to inspect the plants after eight weeks of flowering, he was stoked by the sight of Mr. Power Planter’s results. He happily sniffed around the growroom, busily made notes about the plants’ characteristics and took some photos. “Making a decision is not going to be easy indeed,” he told Mr. Power Planter. “And, of course, I also need to include the actual dry end-products into my choice.”

Yielding Kush

Once Mr. Power Planter had harvested and dried his entire White Russian x OG Kush crop, the average yield turned out to be about 90 grams per plant, which Mr. PP considered highly remarkable for an experimental strain. He had also gained an abundance of heavily resinous leafy material from the harvest that would later be processed into plenty of primo hashish. Without a doubt, this new Serious strain had proven to be a supremely productive hash plant as well.

Simon was keen to get some detailed feedback as soon as possible. Given the sheer mass of buds harvested, test-smoking them all in a short period of time would be an impossible task, so Mr. Power Planter—together with a couple of friends—decided to focus on a range of selected specimens from each of the four lines.

Serious Testing

All of these superb and incredibly frosty buds looked and smelled like true champions. The fuel scent produced by two of the lines had not only survived the drying process but had even gained in intensity, though mixed with notes of sweetness and spiciness. The other two lines were sweet and savory, also promising a delicious taste experience.

Test-smoking the dried buds felt like an exciting feast. The guys weren’t surprised at all when every single nugget they sampled turned out to pack a jaw-dropping indica punch that brought on a tremendously strong sensation of stoniness and relaxation—one potent enough to astound even jaded smokers like Mr. Power Planter and his pals. As Mr. PP reported: “This is eye-rollingly intense marijuana coming with all the hallmarks desired from a mighty Kush strain—a full-blast body-and-head turn lasting for hours and providing a deep, long-lasting breath of blissful relaxation that gives you glazed eyes and a feeling of having your head in the clouds.

“These indica-driven effects are great for unwinding and alleviating stress and pain, so I’m sure that Serious Kush will become very popular with medical patients. Some of the buds also revealed a lofty sativa effect after the first tokes—which sooner or later gave way to that mighty indica hammer, though. As for the flavor, all the buds delivered an intense burst of spicy sweetness that lingered on the tongue and palate very long—a yummy full-mouth taste that was deeply enjoyed by all of us.”

All four of the potential Serious Kush lines had passed Mr. Power Planter’s test grow with flying colors. After Simon was able to test a selection of the dry buds himself, he reported several weeks later that he’d chosen line number three as the winner—one of the two lines with a powerful Kush aroma—and would continue the breeding process with the parental combination from which it had emerged.

It didn’t take long for Simon to announce the official name of his new strain, Serious Kush, and promise that it would hit the market in early 2017. Mr. Power Planter and his friends were absolutely certain that when it did, Serious Kush would capture the hearts of Kush fans everywhere. The first official confirmation came when Mr. Power Planter’s friend Cloudz entered Serious Kush (at that point still called White Russian Kush) into the ICMag Cup 2016 and took home third place in the Indica Growers category.