| Gata, Yes, what The Mohave Kid said. For a specific example, if you were to hand pollinate two heirloom tomatoes, those seeds would produce an F1 hybrid tomato that would be uniform and maybe better than either parent variety, so you might like your F1 hybrid a lot. But if you were to save seed from your new F1 tomato, those seeds would be F2 seeds (second generation seeds) and all sorts of recombinations of characteristics would occur and very few, if any, would be like your F1 hybrid. Some might be very weird and possibly, if you grew a lot of them, you might find one very similar to your original F1 hybrid. You could even conceivably find a recombination that was even somewhat better then your F1 hybrid. If you want to grow more of your F1 hybrid tomato, without recombining vast numbers of different combinations of the two parent's different characteristics, you need only to repeat the cross using the original "pure" heirloom strains. Or, as an alternative, you could simply grow cuttings from your original F1 hybrid cross. If you had a lot of space to grow thousands of tomatoes, you could stabilize a new open pollinated version of your F1 hybrid by growing enough F2s to find a single plant much like the F1, saving as many seed as possible from that plant (you could even multiply it by cuttings to increase that seed yield) and then grow a lot of F3s from that specific selection. Then look through all of your F3 tomatoes for one or two plants very similar to what you are trying to stabilize. The F3s will still be showing a lot of new variations, but they will be more noticeably related to the self pollinated F2 individual that you selected. You will be filling compost piles with tomato plant rejects. You may find only one acceptable plant in a thousand or ten thousand. But each new generation, from F3 to F4 to F5 and so on, will show more convergence toward your desired new tomato, provided you ruthlessly select only the best for the seed of your next generation. By repeating this for several generations you will have stabilized an open pollinated version of your original F1 hybrid tomato. If you were growing lots of plants in each generation and keeping only the very best it is conceivable that your stabilized variety could be even better than your original F1 hybrid variety. (And you will have created a mountain of rejected tomato vine compost as a by-product.) So now you would have a stable superior tomato that you could cross with some other open pollinated variety to create a wholly new F1 hybrid tomato, and the madness could begin again. As you see, it is really much easier simply to repeat making the original cross to produce more F1 hybrid seed than it is to save and grow very many seeds from them in a multi-year effort to stabilize the new tomato as an open-pollinated version. Some F1 hybrid seeds are expensive because hand pollination may be required. Some F1 hybrid seeds cost less because they have found a way to make the cross without hand labor or with much less hand labor (or with cheaper hand labor overseas.) For example, economical F1 hybrid corn is produced by lopping off the tassels of the plants of the "female" variety to prevent self pollination. These female plants are grown in rows alternating with the "male" variety which gets to retain its tassels. The wind just carries the pollen from the tassels of the male variety to the silks of the female variety and F1 hybrid seed between those two varieties is produced on the cobs of the female variety very inexpensively. I hope that explains how F1 hybrid vegetable seed produce uniform plants. They are uniform because each has the same set of pure-strain parents. Incidentally, if you have the space to grow quite a few plants, plant breeding can be an interesting hobby. MM | 
