Every experienced gardener you talk to has their own preferred method for preparing and storing seeds for planting. Some swear by paper envelopes. Others will use only glass jars.
Each recommendation you get comes with a long list of dos, don’ts, and a few nerves. Take the topic of plastic containers, for instance.
Some folks swear that storing your seeds in a plastic container will ruin them for sure, whereas others claim to have been doing so for years with no problems whatsoever.
What’s the real story? Can you store seeds in plastic containers or not?
Yes, you can store seeds in plastic containers without ruining them. However, you should never store your seeds in airtight containers regardless of what they’re made out of because trapping moisture in with the seeds will cause them to rot.
It is a common misconception that you cannot store seeds in plastic containers. There isn’t anything inherently harmful about plastic.
In fact, it is not only possible, but it can be as effective as any other way to keep your seeds safe and dry.
However, it is important to remember that any airtight container will trap moisture and eventually ruin the seeds.
In the rest of this article, we will discuss some tips and tricks for storing seeds successfully, as well as how to avoid ruining them with trapped moisture.
Plastic is Not Inherently Harmful to Seeds
There seems to be something of an old wives’ tale going around concerning the use of plastic for storing seeds.
I’ve heard people claim that the plastic will leach chemicals into the seeds and make them sterile or even poisonous.
I’ve also heard people say that the plastic will absorb moisture and release it into the seeds and make them rot out. Neither of these things is true.
Plastic, in and of itself, is not harmful to seeds. In fact, many commercial seed companies store their seeds in plastic before they sell them. There are only two times you need to worry about using plastic for seed storage.
The first is if you are repurposing a plastic container that is used to hold anything that could be harmful to the seeds. Oils, acids, chemicals, things of that nature.
If you are unsure, it is always better to pick another container or buy a purpose-made one so you don’t risk your future crop.
The second time you need to worry about using plastic is if the container is airtight. As we will discuss later, it is important that seeds are stored in a dry environment.
If your plastic container is airtight, then it may actually increase the chances that it will trap moisture in there with them. Not good!
When Storing Seeds, Moisture is to be Avoided at All Costs
The number one rule of storing seeds is to keep them dry. Seeds can be stored in a variety of different containers, but it is important to make sure that the container you choose is, generally, not airtight if the seeds contain any moisture whatsoever.
That’s because moisture can cause the seeds to rot, and you definitely don’t want that.
Now, an airtight container might be theoretically preferable since it can keep moist air out, but most of the time you won’t be able to totally dry out your seeds and then purge the air from their storage container.
Be Cautious of Using Desiccant Packs
Airtight containers are not the only way that moisture can ruin your seeds, however. Another common mistake people make is using desiccant packs in their seed storage containers.
Desiccant packs are those little silica gel packs that you find in various products that are always labeled “do not eat”.
They are designed to absorb moisture from the area around them and they are usually good at their job.
On the surface, these handy packs seem like a good idea for protecting seeds from moisture intrusion.
However, the problem is the moisture, once absorbed, is trapped in the pack, and thusly trapped in the container with, and maybe against, your seeds. You don’t need me to tell you that is not great for their longevity!
It is possible to use desiccant packs with success, but you must make sure to check on them regularly and rotate them, and ideally they won’t be right up against your seeds.
The Best Way to Store Seeds is Simple: Keep Them Cool, Dry, and Dark
So what is the best and easiest way to store seeds if you want them to last? The answer is actually pretty simple: keep them cool, dry, and dark.
Seeds can be stored in a variety of different containers, from mason jars to plastics ones like Tupperware to Ziploc bags.
As long as the container you choose can keep the seeds dry and doesn’t expose them to too much light, you’re good to go.
The ideal storage temperature for most seeds is around 40 degrees Fahrenheit (4 Celsius), but some can tolerate temperatures as high as 80 degrees F (26 Celsius) without issue, so your fridge is not necessarily required.
Just make sure they are not subject to extreme swings in temperature, as that can also shorten their lifespan.
All told, if you store your seeds in a cool, dry place out of direct sunlight, they should last for many years.
Tips for Getting the Most from Plastic Storage Containers
If you are dead set on the convenience and durability of plastic, but still don’t trust it 100%, you still have options.
You can line plastic containers with wax paper, or even better, put your seeds in paper envelopes or pouches before placing them inside a loosely sealing plastic one.
This can really help with the organization while minimizing the usual drawbacks of plastic.
You can also make sure to thoroughly clean and dry any plastic containers you do use before storing your seeds, and if possible, try to find BPA-free options.
BPA is a chemical that has been linked with all sorts of health issues, and though it isn’t associated with seed failure it’s probably best to avoid it if you can.
As long as you take some basic precautions with plastic containers, they can actually be a perfectly good option for seed storage.
Tom Marlowe practically grew up with a gun in his hand, and has held all kinds of jobs in the gun industry: range safety, sales, instruction and consulting, Tom has the experience to help civilian shooters figure out what will work best for them.