Everything You Need to Know About Saving Heirloom Seeds

Do you hate to see your favorite tomato plant wither and die at the end of the growing season? Saving heirloom tomato seeds is fun and easy, and the best way to preserve the genetic diversity of these delicious and beautiful plants.
Why do You Want to Save Heirloom Seeds?
If you look into the prices of heirloom seed stock, you will soon realize that heirloom seeds are a little pricier than modern varieties. Saving the seeds from your heirloom tomatoes just makes good, frugal gardening sense.
How to Save Heirloom Seeds
Saving tomato seeds can be as easy as spitting the seeds out of your mouth into a piece of newsprint or a napkin, and waiting for them to dry. In fact, the very first tomato seeds added to Seed Savers Exchange’s seed library were delivered in this manner.
Fermenting tomato seeds is a little more difficult, but not by much, than described above, but is probably the superior method of saving tomato seeds. Fermentation separates the tomato seed from the “goo” that surrounds them and keeps the seeds from germinating inside the tomato fruit.
Tomato Seed Saving Supplies
Mason jars, cups, or sandwich bags
Lids or plastic wrap
Sieve or sifter
Paper plate, newsprint or coffee filter
Step 1:
Take the tomato you want to save seeds from and cut it in half along the equator of the tomato. If it’s a small variety like a cherry tomato, you can pinch the tomato in your fingers and the insides, including seeds, will squirt out. Add a few tablespoons of water to the gooey mixture.
Step 2:
Using a spoon, scoop out all the seeds and goo inside and place it inside your jar, cup or sandwich bag. Label the container with the name of the tomato variety you are saving. This is important because you won’t remember later, especially if you are saving a lot of different tomato varieties. If your jar or cup doesn’t have a lid, place a piece of plastic wrap over the top. Poke a little hole in the plastic wrap to allow for some air to flow in and out.
Step 3:
Set your container of in a warm spot in your home — next to a sunny window is ideal. After two or three days you should get a layer of mold (it can be white, black or green in color) to form at the surface of the tomato goo and water mixture. Give them it a good stir to ensure the seeds are all separating from goo. Later that day (or even the next day) go back and see if the seeds have settled at the bottom. If so, take the container and pour out all of the smelly mixture into a sieve or sifter and give the seeds a good rinse under the water faucet.
Step 4:
After you have rinsed your tomato seeds, place them on a paper plate or piece of wax paper to dry for about a week. Try to make sure your tomato seeds aren’t touching or piled on top of each other. This will make the seeds take longer to dry. During the week that they are drying, stir the seeds to make sure they are drying evenly and not touching. After the week is done, package seeds for storage after you have properly labeled them.
One tomato plant can produce more heirloom tomato seeds than you can possibly use. I like to share my tomato plants with friends and family. Sharing heirloom tomato seeds means that if anything ever happens to my collection of seeds, I know there are people out there who I can turn to for more seeds. Since saving tomato seeds is so easy, it is a good idea to teach family and friends how to save heirloom tomato seeds so they too can create their own seed collection of their favorite tomatoes.
Get the techniques you need to grow healthier heirloom tomatoes year after year!
Click the link below and save when you join the online Craftsy class Growing Heirloom Tomatoes and enjoy hours of up-close instruction from gardening expert Marie Iannotti!
By Ramon Gonzalez

Want more details about this and other DIY projects? Check out my blog post!

Frequently asked questions

Have a question about this project?

  1 question
  • I have saved heirloom tomatoes for last 3 years now. I love planting them and sharing them with family and friends too. I save mine however a little differently. I cut them open like you explained. Only I wash mine out immediately and then put them on a paper towel to dry. Write the name on my napkins. After they are fully dried, I fold the napkins and place them in a freezer bag, put them in the freezer until it’s time to plant seedlings the following year. Is there anything I’m doing wrong with this method?


Join the conversation

  • David Selman David Selman on Dec 01, 2014
    Thanks for your article about heirloom seeds. Over the past few years, we have learned a lot about the importance of growing our own vegetables to stay healthy and avoid the problems of commercially grown products with GMOs.

  • Douglas Hunt Douglas Hunt on Dec 02, 2014
    Great advice.