I've learned the hard way about cross pollination of cucerbits and hybrids, after saving Spaghetti Squash seed over three years of fun, and ending up with a giant patch of yellow zuchinni. I understand the difference between hybrid and heirloom tomatoes and have both. I have done some reading but don't seem to be able to find a solid answer to if tomatoes cross pollinate if they are close to each other. May I ask what others have found based on their experiences? Have you been able to save true seed from an heirloom tomato even if it is in close proximity to another variety?
I've saved seed from the Manx Marvel tomato for many years now. You can't get it in the shops and a friend got hold of 12 seeds from the USA that we grew on together with a few other friends. Tomatoes have what is called a "perfect flower" it has all the parts to self polinate and shouldn't cross with other varieties even if they're right next to each other.
Tomatoes are self-pollinating, and don't hybridize even if two are planted right next to each other. Other vegetables, like squash, cucumbers, etc. rely on pollinators like bees, wasps, or an avid gardener with a small paint brush!
Tomatoes with big open flowers, such as Brandywine, have open stigmas that in theory can be sete_011 cross pollinated by others. The vast majority of tomato varieties, probably 99%, have flowers with stigmas that remain enclosed by the anther cone, so they can only pollinate themselves. Most references say you can save seeds from heirloom types without fear of cross pollination. I have been saving some of my tomato seeds for a few years with no change of traits. I have a yellow cherry tomato that I've grown through about five generations, and it remains yellow each time. Yellow is a recessive trait, most of my tomatoes are red, so if there was a cross, the offspring should be red. Also, if I understand correctly, the cherry trait is also recessive but that has also remained true. I don't know if this is copyrighted so I'll just link. I think the potato leaf trait is also recessive. The two that I have with big open flowers are potato leaf types, and this year they grew true too, so I think they didn't cross pollinate either. The dwarf trait is recessive too, and my saved dwarf seeds are all growing dwarf. So I think so far, my own seed saving agrees that you don't have to worry about it much with tomatoes. I cover squash blossoms with organza gift bags so that don't have access. Then I hand pollinate and re-cover the flower. So far they all breed true. That does mean watching them every day, since they are only receptive about a day. I just cut off the male flowers and stick the anthers into the stigmas of the female flowers and spread the pollen around a little. Beans and peas are good for seed savers, since they don't cross pollinate. Spaghetti squash and zucchinis are both Cucurbita pepo so cross pollinate easily. Some other squashes (Pink Banana, Buttercup, Red Kuri, Galeux) are Cucurbita maxima, which shouldn't cross with C. pepo. Butternut squash is C. moschata which shouldn't cross with C. pepo or C. maxima. Key word is "shouldn't".
All squash and zucchini will cross,,,good thing is the next generation is sometimes better than the original !
@Daniel W - That must take a lot of patience to bag and hand pollinate squash I sometimes help out my zuchinni with polinating. Thank you for the information and the link. Gives me a bit more confidence. @marlingardener - thank you.... I have a few paintbrushes nicked silently from hubby's workshop. @mart - the power of zuchinni pollen I sure had a lot of fun until I was surprised with so much zuchinni that year. I ended up with 16 zuchinni plants in total. I had them in a box on the road side with a "PLEASE TAKE" sign after a while hahaha I'm seperating my spaghetti squash in another pasture from my others this year. 4 acres away from each other. I subscribe to a Canadian farming magazine that thankfully last year outlined all of the groups of cucerbits and who cross pollinates with who. I can PM a copy of this if anyone is interested. I can't link it. I want to keep my Gold Nugget true for seed saving. I usually harvest about 60 spaghetti squash and 30 Gold Nugget Buttercup. My season is too short for other varieties, although I did grow First Taste Kobocha last year. But it can cross with the Buttercup, so I'm choosing the Gold Nugget Buttercup. I share with family and neighbours, usually keeping about 30 of the spaghetti over the winter into spring, and most of the Buttercup.
