Ground cherry improvement Europe

JesseI · September 12, 2025, 6:09am

Ground cherries is interesting new crop to domesticate, but unfortunately domesticating in many cases is like looking for a needle in a haystack. I can sow tens of thousands of seeds to look for the most cold tolerant, but besides that the most interesting traits are only evident later in their life cycle when I don’t have as many plants. That’s why it would be good to have as many people growing as many plants and looking for interesting traits. This community might still small to easily find significant mutations, but it’s more likely than me byself. This year I had some 30-40 mature plants and I don’t think I will have more than 100 in the near future.

Traits that I find interesting are fruits size, lobes in the fruit, amount of petals (latter 2 are related to fruit size), amount of fruits in leaf nodes and possibly some growth habbits, although not sure what would be best. Fruit not falling once they are ripe would be useful as well, but that might be hard as it either is or is not. Fruit size could be improved incrimentally by several different mutations.

This year I thought I would really make the effort and try to select for the biggest fruits. For that I bought a precision scale (only 20€). I’m selecting for earliness and fruits size so I first saved a patch of the earliest fruits. After that I have started to scale every bigger fruit and selected the biggest. At the monent I have had cut off at 3.5g. There has been one plant that is doing clearly the biggest fruits; almost all over 4g when otherwise there haven’t been many over 4g. I don’t know if that one plant is special or if the size is relateted to the fact that it doesn’t have as much competition. I still save fruits from that plant separately. I save all over 3.5g to keep some variance and try to slowly move the limit up in the coming years.

Biggest fruit still didn’t break 5g, but fruits have gotten bigger the more ripens. I have picked them daily and some have been little underripe because they have ripened so fast over the last few days with warmer weather. I try to avoid that they fall to the ground where they are more easily accessible to rodents.

Only 2 fruits that i picked from plant that makes the biggest and 2 of the bigger fruits from all the rest. Mostly fuits aren’t even that big and 2-3.5g is more common size.

Just slightly smaller than 1€ coin.

I would also be interested in interspecific crosses beyond grisea/pubescens/pruinosa complex. I have tried cross with angulata, but only got 2 seeds that didn’t germinate using angulata as pollen donor. Not sure if embrio rescue would work and if it after that could be used to make back crosses. So I don’t think I will use effort to make those before I have some information if it’s worth the effort. There should be some other species that cross more easily, but it seems to be hard to find any information about it.

Ps. I might have little weird consept of having fun, but I find it exciting to go through fruits and weighing them with a precision scale. It’s like a little treasure hunt. I could take thousands of fruits, weight and sort them by weight. I don’t think there will be that many once I make the final harvest, but should be at least several hundred. It’s even more interesting coming years when I try to see if I can improve on the biggest.

Diane · September 13, 2025, 3:58am

I am growing some Giant Cape Gooseberries developed by Cicada Seeds in Canada. This is the description from their online catalogue.

Giant Cape Gooseberry Mix Seeds

Cape Gooseberry is a delicious fruit native to South America. It is also called goldenberry, Peruvian groundcherry, Inca berry, aguaymanto, uvilla or uchuva. I find these to be much tastier than regular ground cherries (eg Aunt Molly’s). They taste like a sweet and tropical pineapple with hints of vanilla. They barely have any tartness like regular ground cherries.

In the winter of 2023/24, I sourced as many giant and extra sweet varieties of cape gooseberry that I could find from around the world. I grew them altogether, and they produced the largest and tastiest berries I’ve ever eaten. One of the largest berries was 12.3 grams!

These berries require a long season, so I’d only recommend them for folks with long seasons and/or greenhouses. On Vancouver Island, I start these earlier than my tomatoes around early February, and plant out in my unheated greenhouse in April/May. The plants will have ripe berries from late August-October

The round orange fruits grow inside a papery husk. You can tell they are ripe when the husk (calyx) turns tan and papery. Wait until they are fully ripe to eat and they will have a very sweet, tropical fruit flavour with a hint of vanilla. You can even leave them on the counter for a few days or several weeks for an even sweeter taste.

These fruits will actually last for several months in their papery husks on the kitchen counter without any preservation. They make a delightful tropical treat in January!

A shared some with a friend this summer who is an avid foodie and world traveler. He knows the best restaurants in every major city in the world. He said this was the best thing he’d eaten in years!

Cape Gooseberries are fabulous eaten fresh off the plant, as a garnish on fancy desserts, in baking (think cape gooseberry upside down cake), salsa, jam, cocktails, fruit salad, or dried. I like to think of them as “northern pineapples” because they can be used somewhat like a pineapple substitute.

Unlike regular ground cherries that are low growing, Cape Gooseberry is tall (up to 8 feet), which makes picking the fruits much easier. It produces a lot of biomass (leaves and stems) which is helpful for composting in the permaculture garden. Don’t give them the most nutritious soil so they put more energy into berries and less into leaves.

I grow these as annuals, but a friend of mine has overwintered them successfully in Victoria, BC by adding a foot of straw mulch for winter.

JesseI · September 13, 2025, 4:53am

I’m aware of these, but I’m specifically interested in ground cherries, not cape gooseberries. They don’t work well in my short season. I don’t know which might be easier; breeding cape goose berries to be month earlier (like ground cherries are) or getting ground cherries to produce big fruits like some cape gooseberries. I have already quite many crops where cold tolerance/earliness is an issue so it’s nice to have something that grows fairly well as it is and challenge is a little different. Personally I also like the taste of ground cherries more. To me it seems that when people complain about the taste of ground cherries they haven’t waited until they are ripe. They are a lot sweeter than cape gooseberries and have no tartness.

markwkidd · September 13, 2025, 7:06am

In my part of the world, cape gooseberries are considered one of the ground cherry species. Are there other species within Physalis besides Physalis peruviana which are not considered ground cherries in your region?

I have talked so some people in the United States who refer to everything in Physalis as a ground cherry except Physalis ixocarpa and/or P. philadelphica. So I know there are some differences in thought about this topic.

In my work on Wikipedia, I came across information suggesting that there are P. peruviana populations with three different ploidy levels. Maybe the polyploid are “less” ground cherry than other members of the genus because they are less able to spontaneously cross with diploid species.

JesseI · September 13, 2025, 7:37am

If I’m not wrong it’s the official separation and they might be more generialized in general population (is generally is when things look alike, hence several “salmon” that aren’t related to salmon). Ground cherry name comes from the fact that they fall to the ground. Cape gooseberry don’t fall (at least not as easily), hence they are not ground cherries. There is also the differences in region of origin. I just watched an online lecture about breeding both types and I’m quite sure she used the same logic to distinguish those two types.

markwkidd · September 13, 2025, 8:33am

Very interesting. I have grown cape gooseberries at least two years. I’m certain that they fall to the ground the same as other Physalis.

As far as I know the “tomatillo” species are the only ones in the genus that don’t necessarily fall to the ground, but they are often harvested green so that seems kind of consistent. I’ve read a fair amount about Physalis species and breeding, but I don’t think I’ve ever heard of a nomenclature distinction between ones that fall to the ground and ones that don’t.

I have never thought about the origins of the name ground cherry, but I would have guessed it is a “ground” cherry because they don’t grow on cherry trees. Husk cherry is another name I’ve heard.

JesseI · September 13, 2025, 9:27am

I think they might fall to the ground, but it’s not as clear as with ground cherries that fall straight away when they ripen or even before (although some species that have ground cherry in their name like angulata don’t fall to the ground, but generally it seems to refer those more common species that do so). That was one of the traits they wanted to improve and made a clear distinction to cape gooseberries. Can’t remember the name of the lecture, but I’m sure I saw it here first. I’m quite certain it’s official(ish) scietific distinction and every thing else is what’s been muddled by internet. Just quick googling gave one site which said ground cherries (p.pruinosa) also known as cape gooseberries. People just tend to generalize things that look the same.

Personally I wanted to concentrate on grisea/pubescens/pruinosa and their closer relatives. Peruviana is a little isolated as it doesn’t cross with (as far as I know) any of the ones from Mexico area and I don’t know if it even crosses with some species closer to it’s range. So it kinda self eliminated itself.

JesseI · September 23, 2025, 2:46pm

What we got here? Until very recently all the biggest (at least 10 biggest fruits) were from same plant, with handful over 5g and biggest 5,30, but then right at the end there was a couple over 5g from the other plants (I don’t know which) and top it all this beauty. What peaked my interest is that it has 3 lobes instead of usual 2. I can’t say there has not been any since I wasn’t expecting to find them, but I did look all the biggest that I harvested in the last harvest and didn’t see any besides this. Now I’m wondering could it be a sport? I wasn’t counting on sports when I thought about finding big fruited genes, but that would make it more likely to improve size even with smallish amount of mature plants. Whatever the reason I’ll save seeds from this separately and make a grow-out to see how it turns out. I’m a little skeptic that it would be that easy (if finding one fruit from hundreds if not thousands can be called easy), but it’s worth the try. Next year I’m sure to scan all bigger fruits for 3 lobes.

Ashley_Lutz · March 21, 2026, 3:16pm

Hey this is a neat project! I started one last year too but did it the opposite way. Instead of trying to get larger ground cherries I started working on earlier cape gooseberries. Referencing the earlier discussion on this thread my cape gooseberries did not fall from the plant at all. I got lucky with a late frost and managed to save some seed. We’ll see if they’re any earlier this year.

JesseI · March 23, 2026, 11:28am

The problem with cape gooseberry and breeding for earliness in short season is that first you are missing two things in terms of earliness in a cool climate. First is the easy part; increasing cold tolerence and thus getting it to produce as fast as it can. Second harder part is fast traits. Unfortunately fast genes don’t exist in cape gooseberry as far as I know so even if you can improve cold tolerance, you still have a plant that isn’t suited for short season very well. What you really need, and what most other domesticated species have, is modifying the growth with novel natural mutations that will make it more suited for short season. In short, type of a dwarf version. Even when there is plenty of genetic variation in cape gooseberry, realistically it will take sowing hundreds of thousands of seeds and crossing your fingers. That’s why ground cherry is way better option in my mind. Even if the changes of getting bigger fruits are similarly slim, you do get thousands of fruits which can also individually have those mutations (eg. sports). Also I can sow thousands of seeds and have better change of also improving cold tolerance, although that is secondary goal as they can still produce viable seeds with direct sowing as is.

You might want to somehow get to sow as many seeds as possible and putting them in cool conditions early on. Personally I think cold germination must be the easiest way to screen as many seeds as possible. Although I don’t have anything to base this other than common sense, but I believe if seed germinates faster in cold than others it must also grow better in cold. It is a lot of work thinning down from thousands of seedlings, but I don’t really see any other way. One thing I have learned over the years is that it’s better to cull when the first are in the cotyleons and later germinating are emerging. That’s when it’s the easiest and fastest to make the decisions. But there is no easy way of finding those that by growth suit better short season. That’s where you need numbers in mature plants and only way, besides starting to farm them in comercial scale, is to have more people doing it. I remember there was some project in US with both cape gooseberry and ground cherry that was lead by scientists, but used small time growers for just that getting numbers and finding wanted traits. I can’t remember where I came across that trial, what traits exactly they were looking and if it was cross border with Canada. Something similar might be the way to go. That’s why I’m also trying to recruit more people to look for bigger fruits.

Ashley_Lutz · March 26, 2026, 9:49pm

When I read descriptions of cape gooseberries I think like you this seems to be too big of a task to be able to harvest in my climate. People who I know grow them start them in February and harvest much later than my last frost. But last year I decided to try them anyways. I started them in April in a cold greenhouse, overnight temps were only 3C. So I thought they probably wouldn’t grow that’s okay it was just an experiment but they did. I sowed them thick expecting none but almost all germinated. And then they matured fruit in September. Only a few berries not enough to really eat but enough to save seeds. So I think they are more resilient than people give them credit! Anyways it’s not a commercial scale experiment just a backyard for fun project. Ideally I’m looking to sow in April and harvest early September. Maybe if I get enough seeds this fall I can offer them to the community to grow out and do further selection for cold tolerance and earliness.

JesseI · March 31, 2026, 11:38am

People start them early out of a habit, but it really doesn’t help if you can’t plant them early. In some cases it might even delay the cropping. In good conditions cape gooseberry takes 2 month to flower and another 2 to ripen fruits. In colder climate that might be month more depending on the year. Then month more for the main harvest. Improving cold tolerance you would still have that 4 months to start fruiting. Last year I had direct sown ground cherries ripen first fruits 3 month from sowing and they were some 10 days behind of what they could be because of cold early summer. But with mild early autumn I had month of cropping before first frost in september. Only thing really missing is the size of the fruits. Little cold tolerance would help. I could have tried cape gooseberries, but over here there doesn’t seem to be any variance and even less those with big fruits. With the experience I have had with peppers and eggplants, I would say it’s possible to get viable seeds here with direct sowing and protection. I think that would be the way to go if you want to increase cold tolerance. Once you have enough seeds ofcourse.

malterod · April 7, 2026, 8:55am

I’m not sure I can distinguish between the different names and species. For the moment I just treat what I grow as Physalis and then keep what I like. It would help me to get some ideas of what I am growing.

I’ve grown the genus since 2022 and saved seed every year from two different locations - the first with lots of nutrients, watering and the benefit of urban heat, the second outside the city with poor nutrients and faster draining soil. Here are some from season 2023

Here are some from season 2024

Harvested green mid september

Harvested all fruits before frost and left them to mature inside. This picture is from mid february where only the best are still intact:

Season 2025 was first at new location and I had very little fruit from Physalis - from observation I believe soil conditions. From hundreds of plants, some gave fruit. I then kept those in storage again and only about 20 fruits still had flesh in february. Of those, about 10 of them were the most fleshy.

One plant had managed to self-sow from a small test-planting at that location. And then grew the whole season without any irrigation, set fruit and then also kept until february. I saved that fruit individually.

JesseI · April 7, 2026, 9:06am

Tomatillo of some sort. P.longifolia is the supposed wild form of tomatillo so maybe there might be some of that, but likely just some tomatillos.

malterod · April 7, 2026, 9:08am

And which species are that?

JesseI · April 7, 2026, 9:14am

I couldn’t tell which. I haven’t tried to learn to distinguish between the species and realistically it might be quite hard. Also not sure if they cross. I plant them just like they were from the same species.

malterod · April 7, 2026, 9:27am

What features makes you call them tomatillo and not ground cherries? I assume you’re working with several species complexes. It would help me if you could spell those out.

My assumption is you’re working with these three complexes

grisea-pubescens-pruinosa complex (all in section Epeteiorhiza)
peruviana complex
tomatillo complex (philadelphica and ixocarpa possibly angulata - all in section Angulatae)

Is that true?

JesseI · April 7, 2026, 9:55am

Probably. I do not know what epeteiorhiza refers to and couldn’t find explanation with google. I would consider based on crossability and trait proximity. It might get harder to define once you expand to less known species. There might be some species that could be considered based on how they grow ground cherries, but as there isn’t clear information how well certain species cross with other species, it’s hard to make comprehensive listings. As opposed to peppers or tomatoes where there firstly are less species, secondly it’s quite well known which cross with which and to which degree, and in the case of peppers, cultivated species also have long distinct histories that have made them distinguishable. Physalis don’t have that. Tomatillo literally is diminutative of tomato and as far as I know has been used to discribe several species. Ground cherry also has always been more general name and even in spanish you don’t have one distinct name to distinguish for example peruviana and more typical ground cherry species. Even the scientists don’t seem to be certain how to categorize them so yes it’s better to start from the most common and identefiable species and build from those based on what can be crossed into those. My focus for this project is the non tomatillo and non peruviana species (which anyway shouldn’t cross with most common ground cherry species).

Angulata I don’t know how to categorize, but based on it’s looks and that I haven’t been able to cross it with any of the ground cherries I have, I would consider it closer to tomatillo or then it’s own group. Have to try and intentionally cross that with tomatillo.

malterod · April 7, 2026, 10:30am

The sections can be found on the wikipedia page for Physalis: Physalis - Wikipedia

If it is so difficult to separate them from each other, what features makes you call them tomatillo and not ground cherries?

JesseI · April 7, 2026, 12:34pm

I meant some of them. There are about 90 species of physalis, most of which are endemic to fairly small area of Mexico and southern US where they can naturally cross. So there aren’t clear cut definitions which are which. Even within species there are a lot of variation between different areas. Tomatillos do differ quite a lot from most of what you could call ground cherries. The name already implies that the fruits fall to the ground (usually before they are fully ripe). I do not know if all similar species drop their fruits, but that seems to be common charasteric that separates them from tomatillos. Otherwise I haven’t got enough information about more rare species to say if there are some general traits that could be considered one or other by looks. Best would be crossability. There probably are more complexes that aren’t compatible with any of the complexes mentioned. Or there definetely are in the species that are physalis, but only vagualy resemble tomatillos or ground cherries. But probably also in the species that resemble.