Influence on neighborhood veggies on seed saving

[guy]

Hi,

i'm new to gardening and seed saving, so i'm reading on seed saving (seed 2 seed and breed your own veg), but i lack experience to see the big picture, so i'm asking for yours
My concern is about potential cross contamination by gardens from my neighbors or wild plants, in a case of i planed to grow several varieties of each vegetables anyway,

So, vegs for which it doesnt change anything are imbreeders, hand-pollinised vegs, or veggs grown in isolation cages,

it seems to be problematic only for vegs grown with alternate day caging (or with the "spot the hybrid" method, but it is not included here), but with my limited experience of gardening, i cant figure out a vegetable that is both grown with alternate day caging AND that is eaten after pollination occured, as the only example that come to my mind are brassica and onion/garlic families, and they are biennals, so softcore gardeners only buy bulbs and eat the plant the first year

The only threat i see so far is from wild, with wild carrot or wild onion/leeks. (And sometimes old gardeners let some brassica go to seed but not in my neighborhood).

[feldon30]

Tomatoes and Beans are relatively low chance of crossing. Peppers are a higher chance. And then you get into melons and other curcurbits (cucumbers, etc.) which cross over great distances. Unless you are able to hand-pollinate and then cover flowers with muslin or other mesh material to keep bees, wasps, and other insects out, then crossing is likely.

A book such as "Seed to Seed" is helpful.

[guy]

Hi,

thanks for your answer but this was not my question, as i talk about veggies that are not imbredders, or hand pollinated

[josephsgarden]

Pollination is essentially quadratic is nature. That means that a plant is much more likely to be pollinated by itself or its immediate neighbor than it is to be pollinated by a plant further away... As a first approximation: A plant is 100 times less likely to be pollinated by a plant 10 feet away than it is by a plant 1 foot away.

As examples: In my garden last year I grew crookneck, zucchini, and pumpkins for seed. The patches were separated from each other by 100 to 175 feet. The cross pollination rate (as shown by the appearance of hybrids) was less than 2%. That is perfectly acceptable to me as a small scale farmer.

I could have made my patches larger, and planted them in blocks rather than in rows, which would have minimized the crossing even more, but I grow for myself, and for people like me who enjoy a bit of diversity in their gardens.

In corn, with my prevailing winds, I figure that patches are isolated if they are separated from each other by 25 feet. That's about as far as pollen can drift on my average summer winds before it sinks lower than silk level. It seems to me, that about half of my corn seeds are self pollinated.