svg Organic vs. Non-GMO vs. Heirloom vs. Hybrid and more: Decoding Seed Te | Urban Leaf

Organic vs. Non-GMO vs. Heirloom vs. Hybrid and more: Decoding Seed Terms

Looking at a seed catalogue might leave your head spinning with all the different descriptors – Non-GMO, Primed, Heirloom, F2, Organic – What do they all mean? Is it marketing jargon – or really important seed terms? Not only this, but not being able to know exactly what you will be growing and eating can have some consequences in the future. 

In this blog, we will decode these different seed terms for you to help you decide what’s important for your seed shopping.

What Does Having “Organic” Seeds Mean?

The USDA has a pretty tight definition of what it means to be Organic, broadly that they’re grown without synthetic fertilizers or pesticides. The fact that they are grown without pesticides tends to mean that the seeds of organic plants are naturally better at fending off pests on their own – so will be easier to grow in your organic garden.

Did you know that all the seed in our microgreens starter kit are certified organic and non-gmo?



  • More versatile/well-adapting seeds in terms of climate change
  • Benefits both people and the planet
  • More expensive compared to other seeds
  • More labor-intensive

Are Organic Seeds Non-GMO?

Yes, organic seeds are non-GMO seeds! One of the many rules that need to be followed for a seed to be certified organic is that it’s not genetically modified.

What Do Non-GMO Seeds Mean?

GMO means Genetically Modified Organism – and specifically modified by genetic engineering – where genes from a different animal or plant are put into another. So “non-GMO” seeds just means that genetic engineering wasn’t part of the plant breeding process. 

Genetic engineering is mostly focused on cash crops like cotton, corn, and soybeans, so it’s incredibly easy to avoid when shopping for your seeds (in fact it would be hard, if not impossible, for you to find GMO seeds for most of your garden veggies).

So while seed companies aren’t lying when they advertise their herbs and veggie seeds as “non-GMO seeds” – the truth is that it isn’t something you need to be too worried about, as they’re really only sold to large commercial farmers.  

It should not come as a surprise therefore that all Urban Leaf seeds are non-GMO. You can see our complete range here.



  • More versatile and resilient crops produced
  • Helps protect organic farms
  • Good for both people and the planet

Are Non-GMO Seeds Organic?

It depends – while all organic seeds are non-GMO, not all non-GMO seeds qualify as organic. Organic mostly has to do with how the plants are raised, while non-GMO has to do with the genetic makeup of the seed.  

What Are “Heirloom” Seeds?

Just like a family heirloom, these seeds’ characteristics are passed down from generation to generation (of plants that is) and many can be traced back 100, 200 or even 300 years. The big benefit of using heirloom seeds is that you can collect seeds from your plant at the end of the season and when you plant them, they will grow the exact same plant as the “parent”. 



  • You can seed save
  • Less expensive compared to hybrid seeds
  • More ecologically stable
  • Less “high-perfomance” traits - like compactness, flavor, and resistance to specific diseases
  • Often smaller yields

Choosing Between Heirloom Vs. Open-Pollinated Seeds?

These two terms are very similar – basically, an heirloom variety is one that has been open-pollinated for about 50 years or more, which means that its genes are very stable! So all heirloom seeds are open-pollinated, but not all open-pollinated varieties have been around long enough to be considered heirlooms. 

Are Heirloom Seeds Organic?

Not necessarily. While heirloom sounds very pastoral, it only describes the genetic makeup, and it’s very possible that your heirloom seeds were raised with synthetic fertilizers or pesticides, so if Heirloom and organic are important to you, you’ll need to make sure it’s got both designations. 

What Does Having “Hybrid” Seeds Mean?

Hybrid seeds happen in nature all the time – if a bee travels from one type of tomato to another, the seeds from that plant will have traits from both the parents and be considered a “hybrid” of the two. 

Over time, gardeners have found certain plants to produce really great offspring that have the best characteristics of both parents – think a really compact basil plant that is disease resistant with super flavorful leaves (like our GCI Basil). This is a very traditional technique and produces some of the finest seeds.



  • Faster and easier to grow
  • Adapts well to stress
  • Higher and more predictable yield
  • disease resistant crops
  • Developed for high yield, not quality (quantity > quality principle)


What’s The Difference Between F1, F2, And F3 Seeds?

All the “F” terms sound pretty science-y and artificial, but the reality is much simpler and more natural than that. The number just corresponds to the generation of the seed – in other words, F1=kids, F2=grandkids, F3=great-grandkids. 

The more generations, the less the seed genetics will drift and the more luck you would have with seed saving and getting a similar plant in the next generation. Eventually, the F-number would get high enough that the seed would be considered “heirloom” – where the characteristics are totally stable from generation to generation.  

Can Hybrid Seeds Be Certifiably Organic?

Yes! If it’s grown following organic standards a hybrid seed can be certified as organic. 

What Are “Primed” Seeds?

Some seeds naturally low germination rates – like rosemary which is around 30% and can take weeks to sprout. Seeds like this benefit from being “primed” – where they are taken through some of the pre-sprouting steps before they get to you. This increases the germination rate and reduces the time they take to sprout – and while it’s not needed for all plants – can be helpful for poor sprouters. 

What Are “Pelleted” Seeds?

Some very small and difficult seeds can be found in a pelleted form where they are encased in a thin layer of clay. This is a big help when planting because the pellet is much easier to see, handle, and plant. It also speeds up the germination because once watered, it keeps the seed consistently moist until it sprouts. You can find this technique on our lettuce and carrot seeds. 

Choosing Between Generic Vs. Premium Seeds

Seeds are the “smartest” part of any garden – their DNA dictates the plants’ size, flavor, looks, and light requirements. And on a per plant basis, the difference between generic and premium seeds are typically a few cents per seed, so when we’re growing only a few plants we always opt for premium genetics. This means different things for different plants – but high-quality hybrids, organic, primed and pelleted seeds feature heavily in our herb and veggie seed collections

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