No Strain No Gain: Selecting the Best Bud Breed For SCROG Cannabis Growing

By Nigel Salazar | Published: October 25, 2017

Marijuana strain selection is very personal. Unless you grow solely to sell, your top three criteria for what you grow is that you love the taste, scent and high.

If you’re growing in a screen of green, or SCROG garden, you also want to select strains that can well handle that particular cultivation process, which uses unnatural methods to weave, tuck and manipulate plants into a horizontal screen or multi-screens.

Start your selection process by considering the marijuana strains you’re already familiar with growing. You know how they grow, you know the high, you know the taste and scent. If one of your reasons for turning to SCROG is to increase yield so you have more bud from particular strains you already love, you’ll be inclined to grow the strains you’re familiar with.

Here are the phenotypic and genotypic characteristics to be mindful of in plants that do best in SCROG gardens.

1. Can The Plant Handle The Low-Grade Stress?

SCROG growing requires plants that can handle lots of trimming, and the stress of being trained into a horizontal screen.

Some cannabis strains are known to be unstable. When they’re exposed to extreme temperatures, drought, irregular light cycles, inferior nutrients, overfeeding or underfeeding, crowding or rough handling, they respond poorly.

Their poor response results in slow growth, delayed floral maturation, smaller buds, smaller-than-average root mass and hermaphroditic buds.

Plants prone to these difficulties are not what you want for SCROG growing.

Instead, you want hardy, resilient plants that easily handle variable conditions, trimming and low-grade stress.

2. Give Kush The Kiss-Off

Due to marijuana hybridization and long-standing misinformation about cannabis genotypes, describing cannabis as either sativa or indica is no longer accurate or useful.

It’s true that before hybridization, and before Kush genetics penetrated the cannabis genetics marketplace, you could accurately describe most cannabis strains as either indica or sativa. You could see obvious differences between those two main categories of marijuana. You could say, for example, “If it has fat wide leaves, grows low to the ground, and has a bloom phase of eight weeks or less, it’s indica.”

These days, you see plants displaying indica and sativa traits, such as very thin leaves (sativa trait) and short bloom phases (indica trait). This is the result of hybridization.

To add to the confusion, breeding programs have blended pure Kush and Kush hybrid genetics with sativa and indica genetics. These genetic combos would never have occurred in nature. They’re the product of human intervention.

Some marijuana botanists group Kush genetics in with a recently named cannabis category called Afghanica, but even this is a bit of a misnomer, because not all the genetics included in the Afghanica category come from Afghanistan.

In fact, the genetics we call Kush were introduced into cannabis breeding programs in Holland and North America during the 1960s, ’70s and ’80s. These genetics came from landrace strains gathered in and around the Hindu Kush mountain range and its foothills and valleys, which encompass territory in India, Pakistan and Afghanistan.

You might love Kush for SCROG, but my experience is that such strains are the least useful option for this type of growing. Why? Because authentic Kush strains grow low and dense, without much length or pliability in their branches.

They produce popcorn buds rather than longer, wide ones. Their branches tend to be thick and woody rather than thin and pliable. SCROG gardening is based on low-stress training — a process that artificially induces extra branching and horizontal rather than vertical growth.

When you try to bend and train Kush branches in a SCROG screen, they don’t handle the process well. And because Kush strains most often produce dense, nuggety popcorn buds rather than buds that thicken and elongate, they aren’t so ideal for screening. They can become too dense, leading to problems with gray mold and pests.

Check out the below video on how to install a SCROG garden, courtesy of BudsonBuds.

3. Stick With Sativa

This leaves you with two criteria for choosing strains when you’re running a SCROG marijuana grow op.

The first criteria, as already mentioned, is that you want to love the high, taste and yield of what you grow.

The second factor is whether the strain you SCROG can handle the training process and do well growing into and through a SCROG screen.

With this in mind and from what I’ve seen, Scroggers do best with strains that are sativa dominant.

This includes such popular strains as Pina Rita and Jillybean from Subcool Genetics, Durban Poison and Outlaw (Amnesia) from Dutch Passion, and Jack Herer and Blue Dream.

You can also use autoflowering strains, which many growers prefer because they have limited floor space, time, garden/ceiling height, and so need smaller, faster-maturing plants.

If you’re into growing pure or almost-pure sativa strains such as Kali Mist, SCROG offers a way to tame a pure sativa plant’s tendency to grow into a tall, vine-like mess.

Sativa marijuana untrained often has thin, long, weak branches, and buds that tend to be airy and alarmingly weightless.

Not only that, a sativa strain can take three or more months to finish its bloom phase. Untrained, much of that growth goes vertical. Many a sativa grower has run out of grow-room height and had to tie their plant down, or cut the tops off, to keep them from bunching into grow lights or the ceiling.

The good news is that in SCROG grow ops, thin, long, weak sativa branches are often an advantage because they’re easier to train compared to the thicker, woodier buds you often get from indica and Afghanica strains.

The SCROG screen provides branch support, helping sativa buds to develop more thickness than in regular growing profiles.

The caveat is that a percentage of pure sativa or mostly sativa strains react to stress by becoming hermaphroditic and/or by having delayed floral maturation.

Because SCROG requires low-stress training that could trigger negative responses in some strains, you might discover that no matter what type of genetics you use, you’re creating problems that disqualify that strain from future SCROG endeavors.

One last important factoid to share with you: Your SCROG plants should all be female. If you’re growing from seed, use feminized seed, or use clones of non-feminized plants grown from seed and verified as female.

In our next articles on SCROG cannabis growing, we’ll walk you through low-strength training, as well as ideal feeding and lighting for SCROG plants.

We’ve written several posts about SCROG growing that contain valuable additional information for screen of green success:

If you haven’t read those articles, and particularly if you’re not familiar with SCROG-ing, please read them to learn more.