What seeds can be saved that doesnt need isolating from others for cross pollination reasons???
Common or garden varieties of most vegetables can be left to go to seed and those most kept are probably beans and peas and squashes because they are cleared by the end of the year.
Some such as beet can be kept but as they often have to be left until the following year thus taking up valuable ground.
If you are growing F1 hybrids for specific characteristics then saving seeds is not an option.
The longer the seed keeping process goes on, the more the modern characteristics are lost, yeild, size, disease resistance etc., so after 3 years or so you should invest in new seed.
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