In what I read and believe, tomatoes are MOSTLY self-pollinating before the flower fully opens, with a few varieties being more promiscuous.

Also, if you have lots and lots of very aggressive, very hungry bees who will force their way into flowers even before they fully open, you can get more cross-pollination than you would otherwise.

It seems to very from less than 1/2% cross-pollination to a few %, or in some rare cases maybe up to 5%.

I think the confusion comes from differing goals that are seldom stated clearly.

1.
Seed preservationists like gene banks and conservators demand CLEAN lines like museum curators. 0.1% cross-pollination would defeat their goals, so they do whatever it takes to get pure, pure, puuuuure seeds. Even so, they have to "rogue out" each crop and only collect seed form the MOST standard individuals. And they probably have to deal with genetic drift anyway, as the tomatoes self-select to fit better into local conditions of climate, soil pests, diseases, and curator preferences.

2.
Commercial seed producers have to meet federal standards, and would get bad reputations if they sold stuff that was noticeably contaminated. So they plant big blocks and select from the center, and HOPEFULLY rogue out the oddballs. I wonder how much better they do than the "1/2% to a few %" cross-pollination you usually get with zero effort?

3.
People who save seeds at home are very much at the mercy of genetic drift, unless they save seeds from dozens of plants and do a lot of work to save only from "typical" individuals.

Probably most seed savers would be very hard-pressed to even SEE ANY cross-pollination unless it got up above 10% (very rare) and grew more than 10 plants of the same variety. Even then, they would have to notice the oddball, even if one seed they planted WAS cross-pollinated.

If they had 2% cross-contamination, they would still have to grow out 50 plants to have an even chance of seeing even ONE cross. (I THINK. Statistics are not Zathras' strong point.)

If the cross-pollination is less than you could detect in several years of growing a few plants per year from one batch of saved seeds: WAS there any cross-pollination? I think that's "Schrodinger's cross-pollination". It might BE there, but it would take me many generations of plants to even detect it.

Many technically-inclined home seed savers "just want to do it right" and they bag or isolate or bring cuttings indoors. So they can get less than 0.1% cross-pollination by exerting themselves. They may be planning to preserve their favorite varieties cleanly through an apocalypse, or despite Monsanto buying even more legislators.

However, to even SEE the difference in one year of growing, compared to just growing side-by-side without bags, I think they would have to plant out between 30 and 200 plants each way (from bagged seed, or from side-by-side-seed).

That's just to have an even chance of seeing ONE cross-pollinated plant from side-by-side-seed, and hopefully zero in the bagged seed.

Would that even have a 67% confidence level that the difference was real?

My thought is that when I save tomato seeds, I'll use a LITTLE isolation, like 5-20 yards, then simply avoid growing out 30-300 plants of one variety and micro-scoping them to look for crosses and rouges.

But first and foremost: if I noticed even 1-2 definitely cross-pollinated plants over a few years of growing, I would put that variety back onto my list to buy some more clean seeds of this variety from a vendor who does the hard work and already has to prove compliance with standards".

I don't mind supporting ethical seed vendors. In fact I will feel a little bad about multiplying Frank Morton's neat new lettuce varieties and giving them away. But by then, they won;t be "new"!

If they ALL started going out of business, and hobbyists were the ONLY ones preserving heirloom varieties "clean", I might start doing the bags and THEN telling trade partners I jumped through hoops "to keep it clean".

The easiest way to mark your seeds "not totally isolated" is to just say "ex 'Oranje van Goeijenbier'" which means:
"these seeds came FROM a seed parent that was 'Oranje van Goeijenbier', but I make NO claim about who the father was".

("Luuuuke! I aaam your FATHER!")

But I concede: if my goal was to multiply my seeds every year for 20 years, and wind up with a strain at least as genetically uniform as what I started with, and no discernible genetic drift, I would fool around with bags and numbers of parents and painfully precise selection procedures and something to protect against local-climate-drift.

But if I just want to have more seeds for the next few years without buying again, or sharing with other hobbyists, I wouldn't bag tomatoes or lettuce. But then i would not sell them commercially or donate them to high-tech seed bank.

Whether or not I would give them to a local "seed lending library" depends on the library's policy about isolation.

Before I read @Joseph's articles about modern mini-landraces, and then looked into sources of genetic drift, I had more interest in "pure varieties", and still have some twitches of interest. But if it's a full-time job to prevent ALL genetic drift, maybe i would RATHER that my snow peas and snap peas are better adapted to my climate, and slightly different from an out-of-the-box generic OP commercial variety that works "pretty well for any climate".

This may be the first time on any gardening site that I've ever advocated the LESS gadget-y, LESS tinkering approach.

BetNC said:sheesh! Is anyone else as totally confused as I am??

even more puzzling to me is the term open pollinated: on one hand, I've read expert opinions that nowadays there is an almost impasable barrier to pollination by the usual (wind, insects etc) so almost all flowers self-pollinate; this is cited as the reason to be able to plant different varieties next to each other. But on the OTHER hand, I rread (recently in an article on this cite. . Gardening Ideas) that one must be cautious when planting heirlooms; not to plant them next to each other because of cross-pollination.

I dunno.

If the fruit makes alot of tasty 'mater sandwich, that tomato plant will ALWAYS be a staple of my garden!!

LOL, is it all clear now, after reading Rick's post, BetNC?

I'm curious about this statement in your post: "I've read expert opinions that nowadays there is an almost impasable barrier to pollination by the usual (wind, insects etc) so almost all flowers self-pollinate"

I've never heard/seen that anywhere, and have no idea why it would be true. What sort of "barrier" would that refer to? and is it referring to tomato flowers, or all kinds of flowers?

"Self-pollinating plants which fertilize themselves before their flowers open (such as tomatoes and beans) are exclusively self-pollinating. These do not need to be isolated under normal circumstances, since by the time their flowers open they will have already pollinated themselves. These plants also benefit from being shaken if they are grown where wind and/or bumblebees cannot shake their flowers naturally." from http://howtosaveseeds.com/isol...

Thanks, Farmerdill -- that's a good reference that I've now made a note of .

That section about the "self-pollinating plants which fertilize themselves before their flowers open" does, however, go on to say: "Even plants whose flowers are closed during pollination, however, might cross-pollinate under certain circumstances. Self-pollinating flowers can be forced open by hungry insects in areas with few nectar or pollen sources, for instance. For these reasons even plants which do not normally cross-pollinate may benefit from protection from nearby varieties of the same species in deserts or other sparsely-vegetated regions, or if their purity is particularly important."

That said -- I regularly save seeds from beans and tomatoes that are grown in pretty close proximity and have never had any detectable crossing (even with a lot of pollinator activity).

Daniel, I meant to say that I consider even the term "heirloom" to be used so many ways, and so abused by seed vendors, that it's meaning is whatever you want it to be. The statement was true or false depending on what meanings YOU want to assign to the terms. ("Go not to the Elves for advice, for they will say both yes and no.")

When they split that frizzy hair even finer, into "types of heirlooms", I question the real value of the TERMS that start with something whose meaning is NOT agreed upon, and then add even more Humpty-Dumpty-ish specifics and declare "this means what I say it means.

The CATEGORIES named are useful categories, but if someone uses the terms, they might as well define the terms in the same paragraph where they use them, because if no one agrees about the base term, why expect anyone to agree about refinements and sub-divisions of the main term?

We might as well just say what we mean, spelling it out, until some uber-Humpty-Dumpty comes along and makes everyone use the same terminology.

"Heirloom tomatoes fall into four different groups:
1. commercial varieties that been refined for 40 or more years;
2. family heirlooms, which have been passed down through families for generations;
3. cross-pollinated heirlooms, which come about through the natural pollination of wind, insects or rain, of two heirloom varieties; and
4. created heirlooms, in which people cross-pollinate two different heirloom varieties to refine the tomato’s characteristics."


If I get to define them, only #2 are "heirloom tomatoes".

#1 is just an old, familiar commercial variety. It's not an heirloom unless it has a long, non-commercial history.

(I'm Humpty-Dumpty, so words say what I mean they say. I think I'll invent the term "real heirloom" and insist that it has to have a CUTE family story behind it. Not necessarily a TRUE story, but someone has to believe it and think it's cute. And the story has to be at least 75 years old.)

#3 and #4 are just breeders using heirloom stock, or a lucky bee that managed to cross-pollinate two perfect flowers by FORCING his way into one and collecting pollen, then FORCING his way into a bloom on another plant before that bloom was fully pollinated.

#3 and #4 are just modern F1 hybrids, not even stabilized. Just plain hybrids. With classy parents.

I know that some vendors and breeders or writers make a great big whoop out of the idea that someone finally started breeding for flavor ... but that doesn't SOUND as good as smarmy marketeering hype misusing emotion-laden words. They pollute the language for crass lucre.

Maybe it's late on a Friday - I wouldn't really SHOOT marketing flacks for doing their jobs ... that would be "wrong".

Great info everyone, thanks for your thoughts. With heirloom fruit trees the classification is much easier to understand than seed grown plants.

whew!!! if anything, my poor head is spinning even faster!!

@RickCorey aka Humpty-Dumpty I can always count on you for interesting posts, a good chuckle or two and a bit o" stirring the pot with a good dose of tongue-in-cheek humour!! The outlook is that I'll make a full recovery from my fall, but no doctors are willing to say just how long that'll take!!, which is very frustrating. Meanwhile, my Tomato Jungle is half-grown and my new garden helper comes weekly to tie them up (I do the daily watering), so I won't be missing my 'mater sandwiches!

I repeat: I dunno and care only to the extent I have LOTS of red, tasty 'maters for a boat-load of 'mater sandwiches!! It matters NOT to me heirloom, open pollinated or hybrid: my bottom line are results I can see (and taste)!!

I have to agree that I don't much care if it's old or new, just that it is tasty and productive.

yup....... just wanna grow lots of maters!

Newyorkrita said:I have to agree that I don't much care if it's old or new, just that it is tasty and productive.

That's also my #1 priority -- but I continue to try to find OP varieties that work well for me, so that I can save seeds myself instead of buying them (leaving more $$ to buy other seeds... )

My favorite large slicing tomato (as in, BLT one-slab-of-tomato) is still Country Taste, though -- a hybrid.

Weedwhacker said:

That's also my #1 priority -- but I continue to try to find OP varieties that work well for me, so that I can save seeds myself instead of buying them (leaving more $$ to buy other seeds... )

My favorite large slicing tomato (as in, BLT one-slab-of-tomato) is still Country Taste, though -- a hybrid.

I am trying a bunch of new to me red or pink slicers. Including Country Taste (which is because of your recommendation). So I will see which turn out to be the very favorites. I don't think any will be bad, just some better than others.

Was checking plants last night and I have a quarter size green tomato on one of the Golden Girls plants!

Claudia said:Was checking plants last night and I have a quarter size green tomato on one of the Golden Girls plants!

Actually all 3 plants Golden Girl plants have green tomatoes on them!! Not sure how I missed them last night. 2 of the Rutgers have very tiny green tomatoes also!

Claudia said:Actually all 3 plants Golden Girl plants have green tomatoes on them!! Not sure how I missed them last night. 2 of the Rutgers have very tiny green tomatoes also!

Excellent!!

Geranium Kiss, a dwarf, had little orange tomatoes that I ate quickly off the vine. So sweet. They are saladette size, the first ones were small but I see bigger ones forming.

SCButtercup said:Geranium Kiss, a dwarf, had little orange tomatoes that I ate quickly off the vine. So sweet. They are saladette size, the first ones were small but I see bigger ones forming.

Excellent!! Those first tomatoes after you wait the enture season, are always the best ever.

Well after getting over 7 feet tall the high winds today knocked over my cages for my SS100 plants. Several branches are broke now including many with flowers and about 40 or so green tomatoes got knocked off in the ordeal. thank god it didn't snap the base of the plants. I stood them back up and added extra support, now I just have to see if it recovers quickly or if the stress puts a halt on production.

That is bad news! I have had that happen...... well not the 7 foot tall plants...... but have had storms come along and damage plants. Some have continued producing, though not as much. But others were done. Hope you can save them.

ediblelandscapingsc said:Well after getting over 7 feet tall the high winds today knocked over my cages for my SS100 plants. Several branches are broke now including many with flowers and about 40 or so green tomatoes got knocked off in the ordeal. thank god it didn't snap the base of the plants. I stood them back up and added extra support, now I just have to see if it recovers quickly or if the stress puts a halt on production.

That is a shame but my bet is that they recover quickly and start to put out this tomatoes again.