What Does It Mean to Scarify Your Seeds?

Seeds Are Smart

Picture this: A plant is nearing the completion of its lifecycle. It has sensed that conditions are no longer right for its own survival, and so it has focused all its energy on producing seed—hundreds of copies of itself—so that its kind can go on to survive. 

It drops these seeds, and the wind helps to scatter them elsewhere. Wherever they land, the season is not yet right for these seeds to start growing. They need to last throughout the year (or at least the winter) and not sprout until just the right time. 

Nature's best defense against premature sprouting is a hard seed coat to protect the little embryo inside. It takes time and lots of exposure to water to soften these tough seeds up enough so that the outer layer finally lets water pass through and tell the embryo inside it's time to wake up. 

Scarify Meaning

To scarify a seed is essentially hacking this lengthy process to speed it up a bit. You're breaking down the seed's protective outer coating in order to expedite the whole germination process. 

I like to think of scarifying seeds as essentially just helping Mother Nature out by giving those seeds a little push in the right direction. What might usually take days—if not months—to do in the garden, you can accomplish in just 12 to 24 hours with a nail file and a glass of water. 

Let's look at which seeds benefit from scarification and how to scarify them.

Which Seeds Should Be Scarified?

There are some seed varieties, including seeds for wildflowers and native plants, that have very hard seed coatings.

This group includes:

• nasturtiums
• milkweed
• sweat peas
• morning glories
• bluebonnets

These seeds benefit from scarification to increase their germination rate, or chance of sprouting.

There are also edible plants like okra, beans, peas, and corn with tough seed coats. These can be scarified, though many can simply be soaked in water overnight to speed up the germination process. Soaking is often enough for these seeds to start the breakdown of their seed coat so that the seeds can start growing their roots and shoots sooner. 

Pictured above are bush beans that have been soaked in water overnight. You can see how they're already starting to swell with water, which is key for sprouting.

How to Scarify Seeds

To scarify your seeds, you just need the seeds, a nail file (or piece of sandpaper) and a small bowl or glass of water for soaking. Then, you'll follow these three simple steps:

Step One to Scarify Seeds

Using the nail file or piece of sandpaper, carefully rub the outside coating of the seed just until you see the inside, which will usually be lighter than the thick outer coating. You just want to expose a little of the seed without damaging it.

Step Two to Scarify Seeds

Once you have nicked the outsides of all your seeds, place them in a bowl of lukewarm water for soaking. Leave them overnight or for 8 to 10 hours.

Step Three to Scarify Seeds

As soon as you see the seeds start to swell, you will know they are ready for planting, and then you'll want to get them into the ground immediately. The whole process should be completed within 24 hours.

How to Scarify Nasturtium Seeds

Nasturtiums are some of my favorite flowers to grow in the garden.

You can give nasturtiums a jumpstart by scarifying the seeds, which look like little brains, before you plant them. Watch me scarify nasturtium seeds in this video.

And That Is What It Means to Scarify Your Seeds

One of the best things I've learned to do in the garden, my friends, is to think about the plants' goals. I like to work alongside nature, not against it. The objective for every single plant you might grow in a kitchen garden is to perpetuate itself through seeds, to continue its kind on earth.

Plants don't just want to make seeds; they want to make sure those seeds survive and pop up in the garden next year. Seeds with thick outer seed coats are just ensuring the survival of their kind, and when we scarify those seeds, we're working with the plant to speed up the process and increase their chances of success.

Thanks for being here and helping to make gardening ordinary again!