Have you got some old seeds in your shed and you want to know if you can use them? Perhaps someone gave you some seeds and you want to know if they have expired or not?
Whatever your question might be, we have the answer for you!
When it comes to seeds, the last thing any of us want is to plant expired seeds that will produce smaller plants, or not grow at all. But finding out if our seeds are expired or not can be tricky.
Many packages don’t come with expiration dates and we find ourselves guessing when we bought or were given seeds, unsure if they are safe to use or not.
Well, no more! Today, we are here with the answers that you need! Just keep reading to find out how long seeds last and to access a free chart containing over 100 seeds and their expiration dates!
Can I Use My Old Seeds?
The first thing you need to ask yourself when handling old seeds is to ask yourself the following questions:
- Are my seeds alive?
- Are my seeds viable?
- Will these seeds germinate and grow plants?
It’s important to keep these questions in your mind as they will help you determine the health of your seeds and decide whether they should be planted or not.
To find out if you should use your old seeds, you can do a germination test. These tests will determine if your seeds will sprout or not.
While this is a good option, these tests won’t tell you if your seeds will grow into plants that can reach maturity and provide you with a good harvest.
You can use agricultural lab tests for this, but it’s not something most home gardeners will do!
Instead, we will do a germination test on old seeds. If the seedlings seem stunted, then it’s usually best to pick up some new seeds and use these.
Stunted seedlings will have root systems and leaves that are smaller than they normally are.
What Impacts A Seeds Viability?
When looking at your seeds, it’s natural to wonder what could impact their viability. Three main factors can impact the viability of your seeds that you should be aware of. Let’s take a look at them now.
How Old The Seeds Are
Most seeds are viable for 1 to 2 years. After this time, the germination rate will drop for many types of seeds, falling to zero. Instead of buying more seeds than you need, we recommend just buying enough for that year.
That way, you avoid having seeds in your shed or glasshouse that are no longer viable.
What Seed You Have
The type of seed also impacts how long it is viable. Onions and corn for example have a short lifespan and need to be planted quickly.
But seeds like melon and cucumber can be viable for up to six years, meaning if you have a little extra, they can last quite well.
If you purchase pelleted seeds, these should be used quickly too. The pelleting process reduces a seed’s lifespan, giving you a shelf life of roughly one year.
How Your Seeds Are Stored
You will also need to consider the storage of your seeds when looking at their lifespans. Seeds last longer when they are kept in a dry, dark, and cool place.
You will also want to reduce the humidity as much as possible. You can do this by placing seeds in a sealed plastic bag. Adding rice or desiccant packets can help to absorb any excess humidity too.
Make sure that these bags are also stored in a dark and cool place to prevent any heat from interacting with the seeds.
When seeds aren’t kept in ideal situations, their viability and longevity start to decline.
And although they appear lifeless to us, seeds are living things that need to be treated correctly to ensure the best results when you plant them in the ground!
We recommend that you use the following tips to keep your seeds viable for as long as possible!
- Don’t let your seeds get wet or leave them in the hot sun.
- Don’t place seeds in your shed or greenhouse.
- Once you are done with the seeds, store the packet away correctly.
Now that we have covered how long old seeds can be kept and their viability, let’s move on to look at different types of seeds and how long they last.
Flower Seeds – How Long Do They Last?
First up, we have flower seeds. Before we get into how long they last, it’s worth remembering that your seed’s shelf life is determined by how you have stored your seeds.
If you have stored them correctly, then you have a better chance of them lasting longer.
Flower seeds generally last for five years if they are perennial, and annual flower seeds tend to last for three years.
When you purchase your flower seeds, it’s worth writing an expiration date on them.
That way you can check the seed packet quickly and know if they are expired or good to use.
Vegetable Seeds – How Long Do They Last?
Vegetable seeds can be stored in a few different ways, depending on the storage conditions and what seed they are. But seeds that are kept in dry and cool conditions will last longer.
To help you determine how long your vegetable seeds will last, you can use our rough guide below.
Vegetable Seeds That Last For Five Years
- Swiss chard
- Grounds and squash
- Celery and celeriac
- Brussel sprouts
Vegetable Seeds That Last For Four Years
- Artichoke and cardoon
Vegetable Seeds That Last For Three Years
- Asian greens
Vegetable Seeds That Last For One To Two Years
How To Test A Seeds Viability
We mentioned earlier that you can test a seed’s viability with a germination test. You can do this by following the video tutorial down below!
Free Seed Chart
Now, we established earlier the expiration dates of some flower and vegetable seeds, but there are far more seeds out there! To help you with over 100 types of vegetables and flowers, you can use this chart below!
This chart comes from Joe Gardner and is packed full of helpful information, check it out now!
And there you have it! Providing you follow the correct storage procedure for your seeds, you can expect them to last for up to five years.
Of course, this does vary depending on the type of seed and if it has been exposed to sunlight or water, but for many people, it means that the seeds you bought last year can be used today!
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