Can any of my plants cross-pollinate?

[Jeannedelle]

I'm growing a decent sized garden with a variety of vegetables and herbs, and I want to save pure seeds for next year. Can anyone tell me which of these plants can cross-pollinate so I can take the proper action?

I have:
Spinach
Beets
Yellow Squash
Black zucchini
Lettuce
Bush beans
Peas
Eggplant
Red bell pepper
Broccoli
Mustard greens

Italian parsley
Sage
Summer savory
Sweet Marjoram
Dill
Sweet Basil
Oregano
Thyme
Garlic chives
Cilantro
And chives

I also have 4 different types of tomatoes, including an heirloom, but I know those have to be protected from cross pollination

If you have any other advice for me too, I'd really appreciate it! I've only grown tomatoes on my own (with lots of success), so I'm kind of just winging it with the others so far.

[rainbowgardener]

Cross-pollination in general can only happen within species. So your four varieties of tomatoes could cross pollinate each other, if they are in bloom at the same time. The summer squashes could cross pollinate each other.

Doesn't look like anything else on your list can. And of course many of the items on your list like spinach, broccoli, beets, are generally not allowed to flower. But if you want seeds from them, some of them will have to be allowed to flower and make seed. Same with the herbs. Most herbs are usually kept cut back so they don't flower, because the culinary quality of the leaves declines when they flower and seed.

[Jeannedelle]

So just the squash and zucchini need protection?

And thank you for your help!

[applestar]

Yep squash and zucchini are both Cucurbita pepo species and will become cross pollinated by insects. They need to be covered with insect barrier or the blossoms need to be taped shut -- and hand pollinated, then bagged to protect against contamination.

I believe beets and parsley won't be ready to flower and seed until next year. I'm not sure about sage.

Peppers are apparently extremely promiscuous as are mint family herbs in the same species. And they are commonly visited by pollinators and pollen harvesters.

Depending on where you live (please indicate in your profile when you get the chance), it will be difficult to grow some of the crops all the way to seed bearing maturity within the growing season. I'm thinking about eggplants for example which are normally harvested while the seeds inside the fruits are still immature.... Some can be brought inside to FINISH maturing, but depending on if they had bloomed already or not, you may need to hand pollinate somehow.

[jal_ut]

Yes, the squash and zucchini will surely cross.
Chard will cross with beets, but I don't see chard on your list.
As noted, you may not get seed the first year. Plant a beet
root you have kept over if you want it to bloom. Buy one from
the store?

[Jeannedelle]

Thanks so much for all the help!