Frugality in gardening is a skill I hope to someday inherit from my mother. She once grew a 6 foot avocado tree from a pit. Splitting herbs and rooting mint are child's play compared to her gardening tricks.
The one thing she refuses to do is save seeds from vegetables that aren't hers (okay, the avocado was an exception). And this week, Treehugger confirms her suspicion -- even if the vegetables in question are from a farmers market. If the tomato is an open-pollinated variety, saving them is totally fine. If, however, the tomato has been cross-pollinated from other farms or varieties (and it is impossible to tell by simply looking at them), you aren't going to get great results when you plant them in the spring.
Your best bet is purchasing from certified seed producers and banks, who can all but guarantee success when you plant the seed. And anyway, there are other places to save money in the garden - just ask my mum.
Can You Save Seeds from Farmers Market Tomatoes? from Treehugger
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