Reduce Marijuana Stretching
3 min

6 Ways To Reduce Marijuana Plants From Stretching

3 min
Growing Seedshop

Cannabis plants that grow too stretchy and reach for the sky are unlikely to deliver a hefty marijuana harvest. We've got 6 tips to suppress shoot stretching that will help you succeed in cropping a major stash.

Why Stretching Is Bad

Every grower wants to see a cannabis garden packed with trophy colas of dank marijuana come harvest. Excessive plant stretching, whatever the cause, is guaranteed to rob you of this magnificent sight. Lanky cannabis plants with huge internodal spacing are to be avoided at all costs. Yields will be low and bud quality will likely be the same.

Tall, stretchy plants can even be too much of a handful for some master growers. Moreover, for the average home grower or micro-grower, crop space is at a premium. That’s precisely why we’ve put together 6 easy steps to help you prevent marijuana plant stretching from becoming a problem in your grow-op.

1. Choose Your Strains Wisely


The best way to avoid stretchy cannabis plants is to select a high-quality indica-dominant strain to cultivate. Cannabis strains derived from high altitude mountain Kush varieties have naturally evolved a bushy, tight internodal spacing structure. Indica strains are renowned for their squat and stocky appearance and come highly recommended for smaller grow spaces. Old school classics like Northern Lights and Afghan Kush have very short distances between nodes.

At the opposite end of the cannabis spectrum are the sativa strains. Tall, slender and sparse branching sativa-dominant marijuana is less well-adapted to indoor cultivation. Even with early training and pruning, sativa sativa varieties will still stretch significantly during the bloom phase. Many growers will cultivate late blooming Haze vines on a 12/12 schedule from seed in an effort to limit stretching.

Hybrids are often the best alternative. The very best will display a blend of the most desirable indica and sativa characteristics. The Skunk family fits the bill nicely. Super Skunk for a couchlock effect; Lemon Skunk for the high flyers with a taste for citrus; Cheese for the connoisseurs. There really is a Skunk for every kind of stoner.

Lest we forget the “autos.” Most autoflowering cannabis develops just a single main cola with few side branches, excluding XL Super-Autos. Given that most next-gen hybrids usually peak at about 1m in height both indoors and out, autos are probably the simplest solution to plant stretching problems. It’s just not an issue with them. Autos are not for everyone, but for the beginner grower, they are the most forgiving cannabis plants to crop.

2. Take Care Of Air Circulation

Take Care Of Air Circulation

Fans, fans and more fans! Use an intake fan to draw in fresh air. An extractor fan is a must to suck out the stale air. A pedestal fan (or at very least, a clip-on fan) is another necessity. Try to create a gentle breeze effect on your plants. Stems will be weak and later in bloom, branches may snap without wind to toughen them up from vegetative growth onward. Don’t forget to use ducting and to connect a carbon filter to the extractor fan to eliminate odour.

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3. Light Spectrum

Light Spectrum For Cannabis

Get this right and you will reduce stretching in marijuana plants with minimal effort. Blue/white light is best for seedlings and vegetative growth, while the more orange/red spectrum is suited to flowering. To reduce stretching and to keep internodal spacing to a minimum, it’s best to use cool blue/white spectrum lighting that can be positioned close to the plant canopy.

According to old-school cultivation methods, you could use MH or White CFL for vegetative growth, then switch to HPS for flowering. Nowadays, some growers tend to opt for Full Spectrum LED to support the complete lifecycle, but this is still a bit "futuristic" in terms of feasibility.

4. Heat

Magage Temperatures In Your Grow Room

Temperature is a key growth collaborator and inhibitor. Above 29°C spells trouble for cannabis. Too cold and plants will be stunted and dwarfed, too hot and plants will be spindly, burnt and even turn hermie. Heat stress in the upper canopy of the cannabis garden can do more than just burn foliage.

Worst of all, high heat makes shoots grow thinner and stretchy. This turns top colas into worthless, fluffy buds. Growers can avoid this by hanging lamps the correct distance from tops and by maintaining optimal temperatures from seed to harvest.

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5. Space Between The Plants

Space Between The Plants

An overcrowded SOG won’t do you or the plants any favours. Don’t get greedy. If plants are spaced so close together that they are touching and leaves are shading most branches, the harvest will suffer. Plants will compete for light and race up vertically to survive. Long, thin stretchy colas don’t take home any trophies. They just don’t develop properly. Nobody wants a 50cm long stick of fluff or leafy popcorn buds for a stash.

6. Scrog

ScrOG Method

The most effective method to maintain an even plant canopy that results in a harvest of big fat buds is the ScrOG. This technique is usually applied in combination with topping, LST or supercropping during vegetative growth. Deploying a screen and weaving shoots to fill out the grid is the best way to eliminate stretching as a problem.

The wildest of Hazes can be tamed by a ScrOG. That being said, this one is for the more experienced cultivator. Master at least one of the topping, LST and supercropping trio before dropping a ScrOG on the grow-op to combat plant stretching.

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Top-Shelf Grower

Written by: Top-Shelf Grower
Veteran cannabis cultivator originally from Dublin, Ireland and currently on the loose in southern Spain. 100% committed to Top-Shelf reporting until captured or killed.

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