Mar
The terms heirloom and landrace are sometimes used interchangeably, but there’s a slight distinction between these two categories of seed that can influence how they grow and the kinds of results you as a grower could expect to see. In this article, we’ll dive into what makes a strain heirloom or landrace, and how they differ.
Key Differences
Landrace Strains
- Naturally evolved in specific geographic regions over centuries.
- Stable due to natural inbreeding, with some genetic drift.
- Well-adapted to local climates and environmental conditions.
- More genetic diversity within populations.
- Unique traits depending on geographic location.
- Can be harder to grow outside native environments.
Heirloom Strains
- Derived from landraces, selectively bred for stability.
- More genetically stable, less variation within populations.
- Bred to improve cultivation traits (yield, hermaphroditism).
- Easier to grow than landrace strains.
- Retain many original traits of landrace plants.
- More consistent growth and performance for growers.
Landrace Strains
Landrace strains are the most natural of the cannabis seed varieties. They are indigenous populations of plants that exist naturally in the open without any modern genetic influence. In other words, the overall genetic makeup has remained mostly stable through an extended period.
This includes strains like Durban Poison, Swazi Gold, Malawi Gold, Panama Red, Acapulco Gold, etc.
Although these strains are largely stable owing to their inbred nature, calling them IBL (In-Bred Line) is contested, with some associating IBL specifically with a deliberate line-breeding process, rather than a natural evolution through non-selective incrossing.
Still, stability is a key feature of a landrace strain, and when one observes a lot of variety within a population, it is more indicative of external genetics being introduced, which creates a hybrid that is no longer a pure landrace.
Now that’s not to suggest all landrace strains are the same, cause even though there’s a lot of stability within a particular population, there is enormous variety between different types of landrace varieties. For example, African varieties are known for their energetic effects and thin-leaved blades, while Afghani populations are often renowned for their broad leaves and sedating effects. There can even be distinct differences in populations just mere kilometers away from each other, as they adapt to those microclimates.
Even though landrace strains are often stable, most populations have minor variance among plants within the group, owed in part to genetic drift, a natural process where certain traits become more or less common over generations due to chance. Environmental factors can also play a role—for example, if an area experiences a shift in micro-climate, such as years of excessive rain, plants within the population may gradually adapt to favor traits better suited to the new conditions.
Heirloom Strains
Heirloom, in the context of cannabis genetics, refers to varieties that have been taken from landrace populations and then been worked to further represent the overall average population. The goal of developing heirloom strains is often to give growers a chance to find plants that closely resemble the original landrace expressions, but with reduced negative growth traits.
For example, it’s common for landrace varieties to carry a high rate of hermaphrodism, or low yields. Heirloom breeders will look to make heirloom varieties more friendly to cultivators by selectively breeding the line further. In the process, these heirloom strains become more stable, lacking the nuanced variability one typically sees from a landrace population.
Exactly how similar they are to the original landrace strain varies, depending on how the breeder selects as he stabilizes. But for the most part, they will be very close to the original landrace plant, just a bit easier to grow in most cases.
Additional Information
Although there are distinct differences between heirloom and landrace seeds, it’s not uncommon to see the terms used interchangeably.
For growing purposes, most cultivators will go with an heirloom strain, but a lot of breeders prefer going directly for the landrace varieties, which let them make their own selections that they can use, giving them more control.
