Thoughts on Seed Saving with Joseph Lofthouse!

Hello everyone,

With a lot of seed companies currently overwhelmed due to a spike in demand, I am reminded that seed saving is really critical--and so is seed breeding. For me, this has long been a daunting area. Seeds mutate quickly, and I have seen many newcomers to permaculture waste precious garden space on plants that were improperly selected for.

Thankfully, one of our very own staff members is a very well known landrace seed selector: Joseph Lofthouse!  I was going to ask him some questions privately, but instead we have opted to post this discussion here for everyone’s benefit. Feel free to chime in and comment!

So my first question is:

Is breeding seeds difficult?

I ask this because I have often heard that in order to breed seeds one has to grow a certain number of plants to account for genetic diversity. I have also heard that cross pollination with other varieties must be prevented, often by at least half a mile. And I have been told that seeds mutate rapidly and can revert quickly to wild form, even heirloom varieties. What do you think?

My second question:

I would like to save seed and select for a landrace winter squash for my area. How would you go about doing that, from scratch? I have several varieties that I plan on growing this year and I don’t mind them crossing. I have Sweet Meat Oregon Squash, Salmon River, Butternut, and a few others. My main concerns are palatability and storage life.

We’ll start there for now. If it takes you a few days to respond, I understand! I know it’s a very busy time.

I'm not Joseph and I'm sure he will chime in soon but I couldn't resist.

As a botanist I basically just want to wallow in vegetable diversity. Breeding using evolutionary plant breeding is not difficult at all if you let insects and the wind do most of the crossing work. Nature takes care of a lot of the selection and by saving seed from your favorites you take care of the rest. By recognizing the principle of descent, that seeds resemble their parents you can gradually select for whatever pleases you best amongst the traits in your vegetable population.

If you aren't overly worried about purity isolation is often not important. Sometimes you want to deliberately do the opposite of isolation to encourage natural crossing.

Inbreeding depression can become a problem in small gardens but it can be worked around by saving and combining seed from multiple years. If you start with widely different varieties it may take longer for them to become inbred. If they do become inbred you can cross them again. This also isn't a problem if you embrace and trade seed with a like minded community. Then your garden and their gardens become a meta population.

What would be harder for someone who wants to explore a wider range of plant diversity, would be to grow a garden of uniform varieties.

The squash landrace: butternut is a moschata squash the rest are maxima squashes. If you want them to intergrade you will need an interspecies hybrid bridge. That is available as the F1 interspecies squash hybrid Tetsukabuto. Which Joseph used to breed his Maximoss squash. So if I were you I would buy an additional packet of Tetsukabuto. Then I would take all my squash seeds, put them in a container and shake it. Then I'd use the combined seed to plant a squash fence around the edge of my large garden expansion area that's exposed to deer depredation. Then I would save seed from the squash produced and repeat. In the third generation or G3 I might start eating or composting the seeds of any squash I don't super like. I might also start planting seeds from specific squash in a packet and planting that packet in a row near similar types so some of my favorite sub types start to reoccur with regularity.

Thanks for pitching in, William Schlegel! I always appreciate hearing multiple views.
"Where there is no counsel, the people fall; But in the multitude of counselors there is safety."

Joseph and/or William, I want to save my own seeds, and I have some questions:

Question A) What is the easiest and laziest method of saving seed? Could you spend two or three sentences walking through the steps? Take tomatoes for example. I pick a tomato, cut it open and scoop out the seeds, and they're all covered in that pulpy gunk. Am I supposed to rinse them off? Then what? Put them in my dehydrator? Do I need to make sure they receive X amount of "chill hours" or other arcane rituals?

Question B) I grow nearly a dozen different varieties of tomatoes (several slicers, several pastes, several cherries). How in the world do I label my tomato seeds? Suppose I save the seeds from a Black Krim. Who knows which of my varieties it cross-pollinated with? Would you label the saved seeds, "Black Krim-derived Gen 1", or would you just mix all the saved tomato seeds from all your tomato varieties together, and call them "Jamin Grey Mystery Tomatoes!"

Tomatoes saving their seed and breeding with them are close to my heart these last few years:

Most modern tomatoes have inserted stigmas and are most readily pollinated by their own pollen.

Sometimes early in the season a beefsteak will have a messy exserted stigma. Don't save seeds from those messy double or triple beefsteak fruits because the stigma will also have been double or triple and exposed. This rule reverses if you would like to find a few natural crosses.

Some heirloom varieties may have stigmas that are not strongly inserted but come out instead  and are even with to strongly exserted from the pollen tube. These can be a little harder and the most strongly exserted might have a high percentage of off types. High in this case might be 30% at most. Sometimes exsertion is environmentally induced or only early season.

Avoid or isolate exserted types to avoid higher out crossing rates. Seek out and cultivate exserted types if you want higher out crossing rates.

If you were selling seed you would need to separate varieties by 75 to 150 feet or more depending on conditions locally. This rule reverses if you want natural crosses and becomes plant tomato varieties as closely as possible.

You aren't selling seed though but saving it for yourself and maybe to trade with your friends. You and your friends probably like lots of kinds of tomatoes. I sure do. So if you end up with the occasional cross you'll probably enjoy it. Go ahead, save those crossed seeds, and in five to seven generations you'll probably have a new variety.

Personally I haven't found a natural cross from a inserted mother. A barely exserted mother produced a few, and highly exserted closely planted and even dusted with other pollen produced only a decent amount perhaps 30% So I try to cultivate the most exserted tomatoes possible as closely together as possible so I get hybrids.

There is another possibility that Joseph has hooked me on. Some wild species tomatoes are obligate out crossers like tomatillos. Joseph pointed out that a new class of obligate outcrosser tomato can be created. He is working towards that goal and It makes good sense so the project claims more and more of my garden as well each year. We are crossing domestic tomatoes with Solanum habrochaites and Solanum penellii and slowly working towards a tasty strain.

There are multiple ways to save the seed of tomatoes.

Some gardeners simply dry the gooey seeds on paper. Then tear up the paper come planting time. If you use this method, tell people before you trade seed. Some folks don't want it in trade. It will work fine for your own use though unless you develop certain disease issues.

I prefer cleaner seed so I can direct seed it using a seeder and I prefer no chemicals so I ferment my seed until the gel sack starts to break down. This takes 2 or three days usually. It's not a set number of days really just has to be softened enough to spray off. Then I use the kitchen sprayer hose in a fine strainer till all the gooey stuff is gone. Then I spoon it onto a plate (plunking the entire inverted strainer can get seed stuck under the rim) and let it air dry while turning. I place or tape a paper label to the plate and eventually label the paper coin envelope or paper bag with the type of tomato seed, year, and generation if a breeding project.

There are also some ways to clean off that gel with chemicals. A Web search may find you directions for that.

Also there are ways to heat treat the seed to kill seedbourne pathogens. Haven't felt the need yet, but I watched a YouTube video on it once. Can be done if you are fighting pathogens.

Thanks James for suggesting that we take this conversation public! An interesting tidbit, is that the first time Carol Deppe listed one of my varieties in her seed catalog, she called me "Joseph Landreth". So perhaps we were almost cousins for a few months. I often wondered if one of her employees had a lisp, and was saying "landreth" instead of "landrace"?

James Landreth wrote:Is breeding seeds difficult?

I ask this because I have often heard that in order to breed seeds one has to grow a certain number of plants to account for genetic diversity. I have also heard that cross pollination with other varieties must be prevented, often by at least half a mile. And I have been told that seeds mutate rapidly and can revert quickly to wild form, even heirloom varieties. What do you think?

I see a number of  topics in that.

Is Breeding Seeds Difficult

My world view, is that if someone is saving seeds, then they are a plant breeder, even if unintentionally. The very act of saving seeds, even in a highly inbred variety, tends to select for those slight differences that are best suited to local growing conditions. Saving seeds from more genetically diverse varieties, results in quicker adaptation to local growing conditions such as the farmer's habits. For example, I have been selecting for carrots that can overwinter in my USDA Zone 4b garden, without mulching or any other type of protection. They are reliably overwintering. I did the same thing with turnips a decade ago. Now they are a consistent weed in my garden. How Glorious, to not have to plant turnips!

With that definition of plant breeding, some plant breeding is extremely easy: For example, with tomatoes, and melons, save seeds from those plants that you love, and replant them year after year. They will become increasingly lovable over the years. You just collect the seeds when you harvest the fruit. No extra space is required for growing seed, and minimal effort (basically just saving the seeds while eating the fruit).

Other breeding projects are more complicated. For example, beets are not (currently) winter hardy in my garden. Therefore, I have to dig the roots in the fall, and try to keep them alive until they can be planted out again in the spring. Then they take up a lot of space the next year cause beet flowers grow waist high, and can sprawl just as far outwards. So that makes them cumbersome to grow for seed. Easy enough to do, it just takes an extra growing season.

Minimum Population sizes

The tables about minimum population sizes are written for highly inbred crops. Even then, it's easy to grow populations of several hundred plants, even in relatively small spaces. For example 200 corn plants only needs to take up  an area 20 feet by 20 feet. 100 beet plants could be grown for seed in an area about 5 feet by 5 feet. Sure, I might get more seed if I spaced them further apart, but a small beet patch like that would provide enough seed for my personal use for the rest of my life.

The minimum population sizes are more important in highly inbred (stable) varieties than in genetically diverse varieties (like landraces, and some heirlooms).

Isolation Distances

The tables about minimum isolation distances are written for farmers that are supplying the seed for entire nations. If something goes wrong with their seed, it can have long-lasting negative effects for decades. For example, Delicata squash used to be the empress of pepo winter squash, then the farmer that was growing the entire worlds supply of seed allowed it to get contaminated by a bitter gourd. Then sent that seed to the entire world. Delicata has never recovered it's reputation. If that were to happen to a backyard seed saver, they'd just spit out the bad tasting squash, and not grow that particular lot of seed again.

As a small scale seed grower. I taste every fruit, in every generation before saving seeds from it. That way the flavor just gets better and better every year.

For the most part, pollination is a highly-localized event. Out-crossing plants are highly likely to be pollinated by the closest flower, and very unlikely to be pollinated by things further away. It's a quadratic equation, so pollen from a source a foot away is around 100 times more likely to pollinate a plant than pollen from 10 feet away.

And it depends on species. Some plants are 100% out-crossing, while other species are like 99% selfing. And everywhere inbetween.

Purity

Uniformity is for robots that are trying to harvest a whole field on the same day. Humans tend to prefer diversity, and variability.

My basic philosophy towards purity is that it's a public relations strategy by seed companies to sell you fresh seed every year. I  think of "isolation distances" and "minimum population sizes" in the same way. A meme that is propagated to make back-yard gardeners think that seed saving is hard and should be left to the experts only.  

As a small scale grower, I don't care that every squash is exactly the same shape, size, and color. I don't care the the whole field is harvested on one day. I usually want a harvest spread over weeks or months. What I care about are: Does it taste good? Is it highly productive? Every trait other than those two can be variable for me. I don't care about skin color, or leaf shape. I care a bit about fruit size... I like it to fit into my oven. I like to be able to carry it without bringing a crane into the garden.  I like it to store well. Many of those secondary traits get selected for inadvertently. I give squash to the food pantry that are too big for my oven, and therefore, I'm not saving seeds from them. Another of those inadvertent selections I ended up doing was selecting for soft skins on squash instead of wooden shells. That was because if I couldn't cut a squash in the kitchen, then I didn't feel like saving seeds from it.

Franken-monsters

The grand secret of plant breeding was known by the illiterate plant breeders that domesticated every species that I am currently growing. It goes something like this:

10,000 years of illiterate plant breeders said, but didn't wrote:Plants make seeds.
Offspring tend to resemble their parents and their grandparents.
Sometimes a trait skips a generation.

Thank you for illiterate wisdom.

What that means to me as a plant breeder, is that if I start with great ancestors, I tend to get great offspring. Wild traits like poisons, spines, and hellacious odors were eliminated millennium ago. Therefore, when I start with great parent varieties, any crosses between them tend to be great. And the offspring of them, being genetically diverse have lots of opportunities for local adaptation that is better than either parent.  

Sure, sometimes in casting a net wide enough to include those wild relatives, I have incorporated unpleasant traits into my populations. I just shrug, and either select against the traits, or go back to a previous years crossing project.

James Landreth wrote:I would like to save seed and select for a landrace winter squash for my area. How would you go about doing that, from scratch? I have several varieties that I plan on growing this year and I don’t mind them crossing. I have Sweet Meat Oregon Squash, Salmon River, Butternut, and a few others. My main concerns are palatability and storage life.

Grow what you love, without regards to whether or not it crosses. Include a number of different varieties. Perhaps 3 to 5. Then save seeds from what you love. Repeat year after year. The first few years, select gently, mainly allowing the plants and environment to select what lives or dies.  If you want to try something new, so ahead an grow a little bit of it next season. A little pollen isn't going to mess up your population, unless it's something dumb like I did one year by planting a poisonous melon in with my cantaloupes. Oops. I threw away the whole seasons seed production!

Butternut is a different species than the others you mentioned. So crossing won't happen naturally with the others. You wouldn't need to know that. Just save seeds from what you love. The species will keep themselves separated.

To get better palatability, taste every fruit, in every generation, before saving seeds from it.

To get better storage life, don't start saving seeds until they have stored for a long time. It is common for me to cut 9 month old fruits open in the field, and plant the seeds immediately in the spring. They grow fine that way, and don't need to dry first.

James Landreth wrote:We’ll start there for now. If it takes you a few days to respond, I understand! I know it’s a very busy time.

I'm startled at how easy my workload is right now. Yes. I'm doing tons, but I've been preparing for this moment my whole life, so things flow easily. My heart is filled with love for the people, the plants, the animals, the land. I can barely stand to sleep, i yearn so much for the welfare of all.

Jamin Grey wrote:Thanks for pitching in, William Schlegel! I always appreciate hearing multiple views.
"Where there is no counsel, the people fall; But in the multitude of counselors there is safety."

Joseph and/or William, I want to save my own seeds, and I have some questions:

Question A) What is the easiest and laziest method of saving seed? Could you spend two or three sentences walking through the steps? Take tomatoes for example. I pick a tomato, cut it open and scoop out the seeds, and they're all covered in that pulpy gunk. Am I supposed to rinse them off? Then what? Put them in my dehydrator? Do I need to make sure they receive X amount of "chill hours" or other arcane rituals?

Question B) I grow nearly a dozen different varieties of tomatoes (several slicers, several pastes, several cherries). How in the world do I label my tomato seeds? Suppose I save the seeds from a Black Krim. Who knows which of my varieties it cross-pollinated with? Would you label the saved seeds, "Black Krim-derived Gen 1", or would you just mix all the saved tomato seeds from all your tomato varieties together, and call them "Jamin Grey Mystery Tomatoes!"

No chill hours just a brief ferment and a rinse then dry. If your dehydrator is older it might go low enough in temp. If the temp is too high no, just air dry.

If you grow the same dozen varieties each year you can tell them apart so there would be no mystery in a mystery bag. So the rare hybrid will probably look like a thirteenth variety. Especially in the F2 it will become variable. So almost certainly label that bag just "Black Krim" and even in the extreme case at least 70% of its offspring will be Black Krim but more likely 99 to 99.9% will be Black Krim unless you watch you tube videos on emasculating and deliberately hybridizing and follow the steps therein. Or go to lengths to seek out natural hybrids: searching out open flowers, planting varieties extremely close together (touching), and maybe even transferring pollen without emasculating (I do this). It works better for me during the summer to encourage natural crossing in the garden. Emasculated flowers seem to work better inside or in the backyard greenhouse for me.

You're correct I don't intend to market commercially. This is just for personal use.

William Schlegel wrote:Most modern tomatoes have inserted stigmas and are most readily pollinated by their own pollen.
Sometimes early in the season a beefsteak will have a messy exserted stigma. Don't save seeds from those messy double or triple beefsteak fruits

Can I tell by looking at the final fruit sitting on my table, whether it had an exserted or inserted stigma, or must I pay attention to flower blossoms before the fruit forms? ('cause uh, the latter ain't gonna happen. =P)

(I had to do some googling, because I never heard of tomato stigmas before).

If you grow the same dozen varieties each year you can tell them apart so there would be no mystery in a mystery bag. So the rare hybrid will probably look like a thirteenth variety.
[...] So almost certainly label that bag just "Black Krim" and even in the extreme case at least 70% of its offspring will be Black Krim but more likely 99 to 99.9% will be Black Krim

I just bulk-ordered my seeds for the next six years, making and freezing seed packets. So yea, the same varieties year after year.

planting varieties extremely close together (touching)

I do plant different varieties exceptionally close together. Usually it's the pastes with other pastes, and the cherries and slicers together, in the same bed. I space them about 16-18" apart, but as they grow, they do touch, even while pollination is still on-going. They fill up the entire beds, and spill over the sides (I don't trellis), and I usually have four or five 4x8' beds only two feet apart from each other, all full of tomatoes touching.

Jamin Grey wrote:

William Schlegel wrote:Most modern tomatoes have inserted stigmas and are most readily pollinated by their own pollen.
Sometimes early in the season a beefsteak will have a messy exserted stigma. Don't save seeds from those messy double or triple beefsteak fruits

Can I tell by looking at the final fruit sitting on my table, whether it had an exserted or inserted stigma, or must I pay attention to flower blossoms before the fruit forms? ('cause uh, the latter ain't gonna happen. =P)

(I had to do some googling, because I never heard of tomato stigmas before).

With beefsteaks you can often tell from the fruit. The biggest weirdest lumpiest fruits are the result of double and triple blossoms. Their seed is more likely to be a hybrid. But still most 70 to 99.9% will be virtual clones of the mother.

With cherry tomatoes you have to look at the flowers.

Growing them close like that you might get and notice a rare hybrid tomato sometimes they are more noticeable in the second generation when they segregate. Don't let it stop you from saving seed though.

I think I grew 70 kinds of domestic tomatoes in 2017 and that year I saved seed from three exserted kinds. One produced two hybrids out of a few hundred seeds. Another produced none. The third which was an extreme form of exsertion I got maybe 30% by breaking every rule I could and deliberately daubing on pollen.

So if you have 12 varieties, odds of having a super producer of 30% hybrids are slim to none. Odds that if you grow 500 seedlings from your weird looking giant beefsteak fruit of getting a couple obvious hybrids? Possible.

Thank you Joseph!


What exactly is out-crossing?


What's the most challenging landrace that you've bred?

I also could benefit from a better understanding of out-crossing.  I think there might be a couple ways to look at it and I don't know which is accurate.

I seems logical to me that anytime a plant is pollinated by a different plant it has outcrossed. Some plants can be pollinated either way, by themselves or by another plant. With corn for example, in order to eliminate genetic depression in my small patches I often de-tassel some of my favorite plants. I wait till some silks have emerged, allowing some seeds to be self pollinated but then remove the tassel to insure a lot of seeds were fathered by different plants. But is corn technically considered an outcrossing plant? Just because it can be?

Or does outcrossing mean that a plant can't be pollinated by itself at all? I think this might be the case at least sometimes and if I understand it right, is a goal of Joseph and William in their tomato project.  Inability for self pollination insures genetic diversity and variation in offspring.

And then there are plants that are almost always self-pollinated, beans for example and inbred commercial tomatoes including the heirlooms.

Are there plants that naturally have to out-cross, always needing a different plant for pollination? That's important to me at this moment because I have patches of mustard and turnips that survived the winter and are currently starting to make seed stalks. I want them to cross and turn into a  landrace of winter hardy greens that I plant in fall and harvest in late winter into late spring. I've transplanted favored mustard plants into the midst of the turnip patch. A lot of the resulting seed will be crossed in any event I suppose but If they have to be outcrossed nearly all of it will be.

This is such an interesting thread. Thank you all!

Joseph, do you still share your seeds? If so, can a link to that thread or site be shared here? I know I've drooled over them in the past but didn't have anywhere to grow them.

Sonja Draven wrote:
Joseph, do you still share your seeds? If so, can a link to that thread or site be shared here?

I believe the answer is Yes and No...  Here's how to get them ->  http://garden.lofthouse.com/seed-list.phtml

Plants that have to outcross do exist. I would call these obligate outcrossing. The key word being obligate. They have reproductive barriers to their own pollen. They recognize it and reject it.

It's complicated sometimes though. Sometimes plants are oh say 99% obligate outcrossing. Sometimes 99.9%. Sometimes a species will have mutated populations that self a bit more.

Corn tends to outcross but can self.  

Tomatillo has to outcross.

If mustards are closely related enough they will cross. If different enough they will stay mostly separate.

Rare crosses can occur between mostly seperate sorts of plants.

Some plants are only separate physically. So if you bring them together they cross. Others are seperate genetically and if you bring them together they won't cross.

You can grow five squash species together in your garden and they mostly won't cross. Especially if you seperate the more closely related species. Like plant pepo squashes between your moschata and mospermia squashes.

If you grow ten species tomatoes in your garden they will only cross in somewhat predictable ways.

There are multiple species concepts. The biological species concept uses ability to cross. There are also genetic concepts. Some have tried to say if it is X amount different genetically it's a different species. There are degrees of all of this.

Species is an arbitrary human concept. Plants tend to break human rules.

How out crossing works in tomatoes in my experience:

Domestic tomatoes can be almost 100% inbreeding to about 30% outbreeding. This depends in part on pollinators available. They will accept pollen of any other domestic tomato and multiple wild species. Flower structure is the main game changer.

Habrochaites tomatoes range from inbreeding to obligate outbreeding. Domestic can accept their pollen.

Penelli tomatoes are about the same as habrochaites. Except growing the plants is tricky.

Galapagense, pimpinillifolium, and Cheesemanii tomatoes are about the same as domestic. In practice though this means they mostly keep to themselves or only contribute pollen to open flowers.

Peruvianum tomatoes can sometimes accept penellii pollen. The larger Peruvianum complex is a bit complicated. It can be crossed with domestic with difficulty.

Some specific Arcanum tomatoes can contribute limited pollen to domestic. But cannot cross back to the Peruvianum complex.

One specific Chilense population is known for both crossing with domestic and peruvianum. But growing it is elusive.

James Landreth wrote:What exactly is out-crossing?

"Out-crossing" is when pollen from one plant fertilizes a seed on a different plant. It is synonymous with "crossing". The amount of crossing in a variety depends on a lot of things: The nature of the breeding system that a plant uses. The ecosystem. The weather. Farmer selection. Etc.

For example: The average cross pollination rate on domestic tomatoes is around 3% to 5%. The average cross-pollination rate on beefsteak tomatoes might be around 10%. Some of the wild tomato species are 100% out-crossing. The breeding project that has most captured my imagination in the past 5 or so years, is moving a few genes from domestic tomatoes into a population of wild tomatoes that remain 100% out-crossing.

I really value out-crossing, because it makes it mush easier to select for locally adapted varieties. Manual cross-pollination is a good way to increase genetic diversity in a population. Natural crossing is easier, because crosses are generated without labor, and no record-keeping or pedigrees required.

Spinach is a species that is 100% out-crossing. Because there are male plants that produce only pollen, and female plants that produce only seeds.

Common beans natural cross pollination rate is about 1% in my garden, but as high as 5% in a collaborator's garden who gardens near a woodland fringe.

Runner beans natural cross pollination rate might be around 20% in my garden. Bumblebees and hummingbirds really love them.

Squash encourage cross pollination by having male flowers and female flowers. A plant can be pollinated by it's own pollen, but with the vines all jumbled together, and bees flying willy-nilly between them, they are highly cross-pollinating.

James Landreth wrote:What's the most challenging landrace that you've bred?

I started breeding landraces because I live in a very difficult climate for many species.

I have developed a landrace watermelon, but I'm not quite happy with it, cause I can't tell when the fruits are ripe, and they ripen so late in the season.

Runner beans continue to be difficult for me, because they thrive best in a low-elevation, cool, moist, maritime ecosystem, and my ecosystem is high, hot, dry, continental desert.

I have put the most effort into breeding promiscuous tomatoes. They are glorious to work with, because there is huge diversity in the wild tomatoes. And the promiscuous pollination system lets them solve their own problems, that I would have to solve with materials or labor if I were working with domestic inbreeding tomatoes.

Lagenaria squash were very difficult, but I kept planting new varieties year after year until I found a few that grew quick enough to make seeds. Once I was able to save seeds for a couple of generations, then they reliable and consistent for me.

Mark Reed:

Biological systems tend to be fuzzy. Things are rarely black/white in the plant world. They are more like rainbows, or sliding shades of gray.

For example, with corn, the male flowers are separate from the female flowers, and wind carries the pollen from flower to flower. On a day without wind, the pollen will fall approximately straight down, and so the plant will mostly pollinate itself. In a 10 mph wind, pollen might travel about 25 feet before falling to silk level on a different plant. And there is all kinds of turbulence in a corn patch, so things get all jumbled up and fuzzy. Therefore, I'd say that corn is generally out-crossing, because it can and does.

I would say the same thing about squash (bee pollinated).

Spinach is always out-crossing (different male/female plants).

Cabbage/kale/turnips are (nearly always) out-crossing, because they create chemicals inside the flowers that prevent self-fertilization.

Peas, and beans are predominately self-pollinating. Occasionally a bug will break through the flower petals and transfer some pollen, but they usually are already pollinated long before they start attracting bees.

Flax is predominately self-pollinating, because the anthers form a capsule around the style, and they aren't very attractive to pollinators, so they almost always self-pollinate.

Carrots are an interesting case... They are capable of self-pollinating, but the male part of the flower sheds pollen when the female isn't receptive to it. So insects carry pollen from flower to flower. But there might be several hundred flowers in an umbel (all from the same plant), which makes the umbel very likely to be mostly self-pollinated, but with a good dose of crossing possible.  

I would expect bok choi and turnips to readily cross, because they are the same species. Mustard/turnip crosses are less likely, but they may be in the same genera, so crossing may be expected sometimes. Fuzzy, fuzzy, fuzzy.

Not being able to pollinate itself at all would be an "obligate out-crosser". Spinach, cabbage, and the promiscuous tomatoes would fit into this category.

Another phrase used sometimes is "facultative out-crosser". Capable of self-pollination, but having flower structures that make crossing easier. Corn, melons, and squash would fit into this category.

I'm not all that particular that my landraces are only one species. I grow a number of landraces that are interspecies hybrid swarms. I used to grow any species of hot-weather dry bean in the same patch as all the rest of the species, and just call them dry beans.

Well then I'll just have to wait and see what happens with my mustard / turnip experiment. I have single mustard plants completely surrounded by turnip so that should help the odds. Right now I'm mostly eating the stems and flower buds of both, letting them make a lot of side shoots. It's a bumper crop year for them this spring, looking forward to the fresh, tender seed pods.

I think with corn cause of how a leaf is generally directly above the silks a lot of self pollination is prevented, often see lots of pollen caught there, seems like it might actually prefer crossing by pollen that drifts in from the side rather than falling straight down. Maybe that's why if you only have a few corn plants you can end up with poorly filled ears.

I've been shocked since I started paying attention to such things in recent years at how often beans cross in my garden. I'm lucky to have lots of bumblebees which like the flowers and I think some bean varieties are more prone to outcrossing than others. fuzzy, fuzzy indeed. Also when I do grow outs for a  friend who collects them I often find off-types.

Also have random crossing with domestic and pimpinellifolium tomatoes. That one has me stumped cause of how completely closed up the pimpinellifolium flowers are.  

Sweet potatoes are completely without rules.  I got reams of research and years of observation on them and still barely got a clue of when and why they do or don't cross. I'm convinced now however that some plants are self compatible and some are not. To make it more complicated I'm also convinced that some are cross compatible only with a particular other one(s) not just any other one.

I've got a bunch of cold hardy brassicas flowering and setting seed right now.  They include kale, cabbage, turnips, collards, and rutabagas.  I'm going to save all the seed I can for giving out this July for winter gardening.  They're all right next to each and will probably have crossed, but should be cold hardy and edible!

James Landreth wrote:I've got a bunch of cold hardy brassicas flowering and setting seed right now.  They include kale, cabbage, turnips, collards, and rutabagas.  I'm going to save all the seed I can for giving out this July for winter gardening.  They're all right next to each and will probably have crossed, but should be cold hardy and edible!

Some Kale may cross with Cabbage and Collards as all are Brassica oleracea. Since all are edible leaves you will get edible leaves no problem

Turnips and rutabagas are different species so won't cross.

Probably rare exceptions but for practical reasons it should be fine.

My siberian kale is about to bloom. I plan to save some seeds if I can. If not it'll reseed itself and that will work out too. Or a little of both.

William Schlegel wrote:

James Landreth wrote:I've got a bunch of cold hardy brassicas flowering and setting seed right now.  They include kale, cabbage, turnips, collards, and rutabagas.  I'm going to save all the seed I can for giving out this July for winter gardening.  They're all right next to each and will probably have crossed, but should be cold hardy and edible!

Some Kale may cross with Cabbage and Collards as all are Brassica oleracea. Since all are edible leaves you will get edible leaves no problem

Turnips and rutabagas are different species so won't cross.

Probably rare exceptions but for practical reasons it should be fine.

My siberian kale is about to bloom. I plan to save some seeds if I can. If not it'll reseed itself and that will work out too. Or a little of both.

Thanks William!


I've read that rutabagas are the result of cabbage and turnips crossing, though it may be a rare experience. Whatever the results I'm glad they'll be good to eat and hardy through winter.  Off-season gardening is neglected around me

James Landreth wrote:

William Schlegel wrote:

James Landreth wrote:I've got a bunch of cold hardy brassicas flowering and setting seed right now.  They include kale, cabbage, turnips, collards, and rutabagas.  I'm going to save all the seed I can for giving out this July for winter gardening.  They're all right next to each and will probably have crossed, but should be cold hardy and edible!

Some Kale may cross with Cabbage and Collards as all are Brassica oleracea. Since all are edible leaves you will get edible leaves no problem

Turnips and rutabagas are different species so won't cross.

Probably rare exceptions but for practical reasons it should be fine.

My siberian kale is about to bloom. I plan to save some seeds if I can. If not it'll reseed itself and that will work out too. Or a little of both.

Thanks William!


I've read that rutabagas are the result of cabbage and turnips crossing, though it may be a rare experience. Whatever the results I'm glad they'll be good to eat and hardy through winter.  Off-season gardening is neglected around me

Yep there are rare exceptions and that could happen but mostly wont.

Wow! I'm learning so much through this thread! I've never tried saving seeds, but I'm going to try this year!

If you want to grow veggies AND you want to save seeds; It's very easy. IF you only grow one variety of each veggie. Tomatoes are an exception. But with tomatoes you have to grow heirlooms and if you do you will have success with the number of plants a gardener's likely to grow. With tomatoes, from my experience, the only time you'll have a problem is when you plant Mortgage Lifter seeds in a cell or pot marked Pink Brandywine.
With Cucumbers if you also grow pickles your seeds will be mysteries. Peas and beans will be OK. I'm testing growing string beans and lima's in the same garden this year. I've saved lettuce and radish seeds. I save seeds from 3 different size pumpkins grown together. And I grow one zucchini variety which I've saved seeds from for years.
If you've never saved tomato seeds and you're put off by elaborate instructions just use a teaspoon. Dip into a slice of tomato, before you salt it, and put the seeds on a paper towel and mark the variety with an ink pen. Your done! I'm just trying to convince you to do it. Save some seeds. If you want to get technical, get nice clean seeds. Seeds that you can shake into an envelope. Then try fermenting some. But get some seeds saved.
The important parts are growing heirlooms and saving seeds.
That said, I enjoy following the tales of some of you. I enjoy reading about Joseph Lofthouse's gardening experiments

William Schlegel wrote:How out crossing works in tomatoes in my experience:

Domestic tomatoes can be almost 100% inbreeding to about 30% outbreeding. This depends in part on pollinators available. They will accept pollen of any other domestic tomato and multiple wild species. Flower structure is the main game changer.

Habrochaites tomatoes range from inbreeding to obligate outbreeding. Domestic can accept their pollen.

Penelli tomatoes are about the same as habrochaites. Except growing the plants is tricky.

Galapagense, pimpinillifolium, and Cheesemanii tomatoes are about the same as domestic. In practice though this means they mostly keep to themselves or only contribute pollen to open flowers.

Peruvianum tomatoes can sometimes accept penellii pollen. The larger Peruvianum complex is a bit complicated. It can be crossed with domestic with difficulty.

Some specific Arcanum tomatoes can contribute limited pollen to domestic. But cannot cross back to the Peruvianum complex.

One specific Chilense population is known for both crossing with domestic and peruvianum. But growing it is elusive.

I have never seen or heard of all these tomatoes you have listed. Are they from other countries as some of the names suggest? Where would I find any? Would adding a few to my own future land race attempts be of any real benefit?

Cindy Haskin wrote:

William Schlegel wrote:How out crossing works in tomatoes in my experience:

Domestic tomatoes can be almost 100% inbreeding to about 30% outbreeding. This depends in part on pollinators available. They will accept pollen of any other domestic tomato and multiple wild species. Flower structure is the main game changer.

Habrochaites tomatoes range from inbreeding to obligate outbreeding. Domestic can accept their pollen.

Penelli tomatoes are about the same as habrochaites. Except growing the plants is tricky.

Galapagense, pimpinillifolium, and Cheesemanii tomatoes are about the same as domestic. In practice though this means they mostly keep to themselves or only contribute pollen to open flowers.

Peruvianum tomatoes can sometimes accept penellii pollen. The larger Peruvianum complex is a bit complicated. It can be crossed with domestic with difficulty.

Some specific Arcanum tomatoes can contribute limited pollen to domestic. But cannot cross back to the Peruvianum complex.

One specific Chilense population is known for both crossing with domestic and peruvianum. But growing it is elusive.

I have never seen or heard of all these tomatoes you have listed. Are they from other countries as some of the names suggest? Where would I find any? Would adding a few to my own future land race attempts be of any real benefit?

Cindy,

Those are species tomatoes. You can find them online and they do contain rare genetics but most wild species tomatoes do not taste good.

https://www.hrseeds.com/wild-tomatoes here is one source.

Solanum pimpinillifolium, and Solanum cheesemaniae are the two wild species known to taste good.

Some wild species tomatoes like Solanum habrochaites are commonly used as rootstocks or rootstock parents for grafted tomatoes but do not taste good.

Most people do not need wild species tomatoes, but serious plant breeders make crosses with them looking for resistance. Joseph Lofthouse has used a couple species of them to make some hybrid populations. After about 7 generations some tasty ones showed back up!

If you just like tasty tomatoes, I would not go all the way to wild ones. Or at least stick with the two tasty species. Though personally I've found it a delightful journey of botanical discovery it may not be for everyone.

The two tasty wild species contain tremendous diversity and those I would recommend to everyone. Also many modern varieties incorporate wild genes.

Fortunately, Joseph's tomatoes are available and with those most of the hard work has already been done but depending on the population may vary in flavor a lot even still.

https://store.experimentalfarmnetwork.org/collections/tomatoes?page=2

Joseph's tomatoes are at the above link including some wild species such as a diverse population of Solanum habrochaites sold as Neandertomato (these would not taste good).  Solanum habrochaites crosses are a serious long-term project to get back to good flavors but the journey can be a lot of fun for those who love plants. His Q series and Wildling Panormous tomatoes will offer tremendous diversity and the benefit of those first seven generations or so, but some will likely still have off tastes. Some of them may be obligate outcrossing which means planting at least a few plants may be necessary.

If looking for a fun source of resistant genetics in a fully domestic tomato you might try something like Purple Zebra F1 or Sungold F1.  These modern hybrids incorporate small amounts of wild genetics from the wild species for various resistances to common tomato diseases.

https://territorialseed.com/products/purple-zebra?variant=41647593062574

Modern hybrids can be a fun and tasty way to get started with tomato breeding. They will segregate the second year you grow them. Segregating tomato populations are great fun! It is basically like having someone else make a tomato cross for you as the start of a breeding project!

I think the main thing with a tomato landrace or grex is really to look for tomatoes that have open flowers with styles and stigmas that stick out a bit and are more likely to cross occasionally.

Hello everyone,

Thank you very much for all these discussions, they are really useful for us.
I'm working on the development of varieties, and especially Zebra tomato varieties, and I wanted to know if you have any experience in this area, how the stripes pass from one generation to another, and what to have a hybrid F1 zebra, we need both parents will be with stripes.