Saving Tomato Seeds

Tomato seeds from open-pollinated varieties can be saved from year to year. Pick some of the best fruit from the most productive vines, scoop out the seeds and slime from the cavities and put it into a jar. Let the jar sit outside for a few days until there is a layer of mold growing on top (it will stink!), then rinse the seeds off in a sieve, picking out all the mold and scum that is mixed in. Finally, let the seeds dry (use something non-porus, or you'll never get the seeds separated from the surface).

I use canning jars, and let the mold grow with a little scrap of paper towel tied over the top to keep bugs out of the jar.

When the seeds are drying, I mix in a couple drops of food color so I can identify one variety vs another next spring. The photo shows blue-dyed seeds from Oxheart tomatoes. After they air-dry, I'll put some silica gel into the container and let them dry out for a week that way (this will reduce the moisture content to ~5%-8% and prevent mold growth over time). Then, transfer the dry seeds to a sealed container without the silica gel, as I don't want them to dry out too much). The seeds should last many years, some sources say up to 10 years.