The Leafly Strain Guide

This strain guide is very useful and Denali is putting it up as a reference for our patients. All content is from

Strains of medical marijuana refer to the ‘Family’ the plants come from.

Indica and sativa are the two main types of cannabis. Here’s how to tell them apart:

The two main strains of cannabis are indica and sativa

The two main strains of cannabis are indica and sativa

Cannabis is one of the oldest crops known to mankind, with records of its cultivation dating back thousands of years.

Today, it is widely accepted that marijuana has two different species: Cannabis indica and Cannabis sativa. Cross-breeding of the two types has led to a wide variety of hybrid strains with unique characteristics.

The differences between indica and sativa remain a subject of much debate, especially among scientists who study the plant. However, most agree that indica and sativa plants are distinct in a number of ways.


The most accepted way of distinguishing indica versus sativa is by appearance, or what scientists refer to as morphology.


Sativa plants are tall, loosely branched and have long, narrow leaves. They are usually grown outdoors and can reach heights of up to 20 feet.

Indica plants are short, densely branched and have wider leaves. They are better suited for growing indoors.


Besides appearance, indica and sativa plants are commonly believed to have different effects on their user. These effects include:


  • uplifting and energetic
  • cerebral, spacey or hallucinogenic
  • best suited for day use


  • relaxing and calming
  • body buzz or ‘couch lock’
  • best suited for night use

However, no scientific study has confirmed these differences, and there is some doubt about their accuracy. In fact, history suggests a much simpler difference between indica and sativa.

The original classification of Cannabis indica was made by French biologist Jean-Baptiste Lamarck in 1785. (from Leaf Science)

The strain guide will help you understand the characteristics of a named type of cannabis.