As a starter, there are some useful tips from realseeds.co.uk in each vegetable section. Go to Aubergine and at the end of the page is guide on how to save seed for aubergine. Likewise for other veg. Google search on 'seed saving' might also help.

Seeds saved from a F1 hybrid seeds cannot be used again. They tend to be infertile/sterile due to missing chromosomes as a result of mixing with several desirable genes to make them better (supposedly??)...or something like this.

For me personally, I will like to avoid the F1 seeds in future, besides heirloom seeds are making a comeback.

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