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How to Trellis Marijuana Plants to Increase Yields (The Right Way)

Published Date: February 14, 2025

Trellising marijuana plants for higher yields.

How to Trellis Cannabis

Raising cannabis plants is a lot like raising children. When you provide them with love, attention, and what a marijuana plant needs to survive—the right balance of light, nutrients, and care—they thrive, sometimes with astonishing growth. But without proper guidance, they can become unruly, sprawling in every direction like a tangled mess of Christmas lights. This is where cannabis trellising comes in.

Whether growing marijuana at home or commercially, trellising is essential for maximizing yields, improving airflow, and creating a structured canopy that ensures even light exposure. Indoors or outdoors, a well-placed trellis can transform unpredictable, sprawling plants into high-yielding, perfectly shaped specimens.

This guide explores why trellising is so effective, the best materials, and step-by-step instructions for building a system that enhances plant growth. If you’ve ever envisioned a lush, organized cannabis garden bursting with dense buds, keep reading—you’re in the right place.

What Is Trellising Marijuana Plants?

Trellising is a plant training technique in which growers use a structure—such as netting, stakes, or screens—to support and shape the growth of marijuana plants. The goal is to create a flat, even canopy that allows all buds to receive optimal light while preventing weak branches from sagging under the weight of heavy colas.

When done correctly, trellising increases airflow prevents mold and mildew, and ensures that every part of your plant gets equal light exposure. This leads to healthier plants, denser buds, and higher yields.

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Why Trellising Marijuana Plants Boosts Yields

The benefits of trellising go beyond just keeping your plants upright. Here’s why this method can take your grow to the next level:

1. Better Light Penetration

An untrained marijuana plant has an uneven canopy, meaning some parts receive too much light while others remain dark. A trellis evens things out, ensuring every bud site gets the right light.

2. Increased Airflow and Reduced Risk of Mold

Dense, untrained plants trap moisture, making them a breeding ground for mold and mildew. Trellising spaces out branches, allowing better airflow and reducing humidity buildup.

3. Higher Bud Production

When you control plant shape, you can direct more energy to bud sites rather than wasting it on unnecessary leaf and branch growth. This means fatter, denser buds come harvest time.

4. Easier Maintenance and Harvesting

A structured canopy makes pruning, inspecting, and harvesting your plants easier. No more digging through a jungle of leaves trying to find hidden colas.

Types of Trellising for Marijuana Plants

Not all trellises are equal. You should choose the right type based on your growing environment and goals.

1. Horizontal Trellising (SCROG – Screen of Green)

A horizontal trellis, called SCROG (Screen of Green), is a flat mesh screen placed above the plants. As they grow, branches are woven through the screen, forcing plants to grow outward instead of upward.

Best for: Indoor cannabis grows and maximizes limited space.

2. Vertical Trellising

Instead of spreading plants horizontally, vertical trellising uses a cylindrical or upright structure to encourage upward growth. This method is commonly used in outdoor gardens where plants grow pretty tall.

Best for: Growing marijuana outdoors and sativa-dominant strains with long flowering periods.

3. Two-Tier Trellising

Some growers use a double trellis system, with one layer supporting vegetative growth and another holding up heavy buds during flowering.

Best for: Large, high-yielding plants that need extra structural support.

Best Materials for Trellising Marijuana Plants

Choosing the right trellis material is just as crucial as your method. Here are some of the best options:

Plastic Netting – Lightweight and durable, great for SCROG setups.
Metal Wire – Sturdy and reusable, but can be harsh on stems.
Bamboo Stakes – Natural and biodegradable, ideal for individual plant support.
Nylon Mesh – Flexible, easy to clean, and perfect for indoor and outdoor growth.

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Step-by-Step Guide: How to Trellis Marijuana Plants

Trellising might seem intimidating initially, but with the right approach, it’s a straightforward way to support your plants and boost yields. Follow these steps to set up an effective trellis system and keep your cannabis plants thriving.

Step 1: Set Up the Trellis Early

The best time to install your trellis is before your plants get too big. It should be set up during late vegetative growth so plants can adjust.

Step 2: Train Your Plants

As your plants grow, gently guide branches through the trellis holes. The goal is to create an even canopy where every bud site gets light.

Step 3: Prune Strategically

Remove unnecessary lower branches and leaves that aren’t getting light. This prevents energy waste and improves airflow.

Step 4: Adjust as Needed

Plants don’t always behave as expected. Keep checking on them, adjusting their positioning, and ensuring they don’t outgrow the trellis.

Step 5: Support Heavy Buds

Once flowering begins, buds get dense and heavy. A second trellis layer (or additional support) ensures branches don’t snap under their weight.

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Common Mistakes When Trellising Cannabis Plants

Trellising mistakes can lead to poor airflow, broken branches, and reduced yields. Avoid these common errors for a healthier, more productive crop.

🚫 Installing the Trellis Too Late – Trying to trellis overgrown plants can cause stress and make training difficult.

🚫 Weaving Too Tightly – Restricting branches too much can damage stems and limit natural movement.

🚫 Ignoring Airflow – Poor spacing can trap moisture, increasing the risk of mold and mildew.

🚫 Using Weak Materials – A flimsy trellis won’t support heavy buds, leading to sagging or snapped branches.

By avoiding these mistakes, you’ll create a strong, well-structured canopy that maximizes light exposure and boosts yields.

Is Trellising Only for Outdoor Cannabis Plants?

No, trellising isn’t just for outdoor cannabis plants—it’s equally beneficial for indoor grows. While outdoor plants often need trellising to support their height and withstand wind, rain, and other environmental factors, indoor growers use trellising to maximize space, improve light distribution, and create an even canopy.

A Screen of Green (SCROG) method is commonly used in indoor setups. In this method, a horizontal net supports branches and encourages outward growth rather than upward stretching. This ensures every bud site gets equal light, leading to higher yields in confined spaces.

Whether growing indoors or outdoors, trellising is a valuable tool for training plants, reducing wasted energy, and preventing weak branches from breaking under the weight of heavy buds.

FAQs

How high should a trellis be for marijuana plants?

It depends on the strain, but 12-18 inches above the base for SCROG is ideal. For outdoor vertical trellising, adjust based on expected plant height.

Can I trellis marijuana plants too early?

Yes. Installing a trellis too early can limit growth. Wait until plants are at least 12 inches tall before training.

Do all strains benefit from trellising?

Some bushy indicas might not need as much support, but most strains—especially tall-growing sativas—benefit greatly.

Is trellising different for indoor vs. outdoor grows?

Yes. Indoor grows often use SCROG for space management, while outdoor grows use vertical or two-tier trellising for larger plants.

Should I prune my plants before trellising?

Yes. Removing lower growth before installing a trellis helps direct energy to productive bud sites.

Can I reuse trellis netting?

Yes, if it’s made from durable material like nylon or metal. Just be sure to clean and disinfect it between grows.

Final Thoughts on Trellising Marijuana Plants

Trellising cannabis plants is one of the best ways to increase yields, improve airflow, and create a well-structured canopy for healthy growth. Whether you use SCROG indoors or vertical trellising outdoors, the proper setup ensures every bud gets the attention it deserves.

So, give your plants some structure the next time they start growing like wild teenagers. A well-trellised plant is happy, meaning more prominent, better harvests.

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