Orchard People

[00:00:00] Introduction to Growing Kiwifruit in Cold Climates
If you want to grow kiwifruit and you live in a colder climate. You may think you're out of luck. That's because the type of kiwis that we buy in the supermarket grow in warmer climates.
The Latin name for kiwi plants is Actinidia deliciosa. And these small fruits with fuzzy light brown skin and the bright green flesh, they grow in warmer climates like USDA Zone 7 to 9. But luckily, there are some related plants in the Actinidia genus that also produce fruit, and some of them are winter hardy and can grow in colder climates.
So in today's episode, we're going to talk about the Actinidia arguta, which is also known as hardy kiwi vines. These beautiful plants produce grape sized berries that are sweeter than traditional kiwis, and they have smooth, edible skin. And the best of all, they grow in USDA zones 4 to 8, depending on the variety.
if you live in a cold climate, you can grow them.
[00:01:07] Meet the Expert: Iago Hale
In today's show, I speak with hardy kiwi expert Iago Hale, associate professor in agriculture, nutrition, and food systems at the University of New Hampshire. And we're going to talk about the history of hardy kiwis and how to grow them. We'll also discuss some popular varieties that you might consider growing in your garden.
So we're going to hear from Iago in just a minute, but first I want to hear from you. If you send in a question or a comment during the live show today, where we will enter you into our contest. And our prize today is a copy of the book Cold Hearty Fruits and Nuts 50 Easy to Grow Plants for the Organic Home Garden or Landscape and it's by Allison Levy and Scott Serrano.
It's valued at 33. So to enter today's contest just send an email with your question, a comment. Or even just to say hi. And you can send it to instudio101@gmail.com. That's instudio101@gmail.com. And do remember to include your first name and where you're writing from. I look forward to hearing from you.
So now to Iago. Welcome to the show today.
Hi, Susan. Thank you so much. I'm thrilled to be here. This is a great show.
Thank you.
[00:02:31] History of Hardy Kiwis
I'm happy to have you, and I want to know a little bit more about the history of hardy kiwi plants. It sounds to me like they've been here a lot longer than I originally thought.
Yep, they certainly have, and I guess I would start off real quick on just nomenclature a little bit. there's about 50 to 60 kiwifruit species in the genus Actinidia, and there are three different species that are collectively referred to as hardy kiwis because they are cold hardy, and that would be Actinidia arguta, kolomikta, and polygama.
And Actinidia arguta Has really over the last decade or so coalesced in the marketplace around the name Kiwiberry. So when just in all of our outreach and extension we do try to refer to it as Kiwiberry to distinguish it from the larger, group there. But, speaking specifically about Actinidia arguta.
Yes, the history is this history is fascinating. Actually, it is a, whirlwind of the who's who rich and famous from the late 1800s. And the gilded era. The seeds, so all first of all kiwifruit are originally from East Asia. They all originate from, you can think, roughly China is the main place, but many of the species are also found, natively in the Korean peninsula and in Japan.
We often associate kiwifruit with New Zealand, but, it's not actually from, New Zealand. There was a New Zealand plant explorer in the early 1900s that took some cuttings, and they were the first to commercialize, but, kiwifruit has been Foraged in the wild for thousands of years from, China, in China.
But the first seeds of Actinidia arguta, or kiwiberry, were first brought to the U. S., to North America. They're actually brought to Massachusetts by Colonel William S. Clark, who went on to found the Massachusetts Agricultural College, which is now the University of Massachusetts. And this was in the late 1870s, so we're 150 years ago.
And this was at a time, when you look back to the 1870s, that era, there was a lot of fervor around, bringing in botanical specimens, specifically from Asia. Hundreds, if not thousands of specimens were brought in over the next few decades. There was a lot of plant exploration going on. And so kiwiberry was one of those acquisitions that happened at that time.
So was it brought in because of the delicious fruit? What was the appeal of this plant?
It's a little hard to say. and the reason I say that is that it was, so it was brought in 1877, the original seeds. What we know, looking at historical records, and I owe a lot of this information to a good colleague of mine, Bob Guthrie at the University of Minnesota, who has combed through, and this is not hyperbole, combed through, Close to 10, 000 historical documents trying to understand the, history of the species in North America, how it was brought in, how it was disseminated.
But what we know from a lot of Bob's very careful research is that after it was brought in 1877, within the next couple years, We know that it was distributed to multiple botanical gardens throughout the U. S., and by the early 1880s, it was in catalogs of plant nurseries in the northeast. George B.
Dorr's Mountain Desert Island Nursery up on the coast of Maine, we have records from nurseries in New York and Long Island. by the early 1880s, This was being sold as a plant. The issue, and I think this is what derailed, work on the species as an agricultural crop versus a food crop, is that these original nurseries lumped it in with their ornamental vines.
And if you go back to that time and look at these catalogs, Actinidia arguta, not referred to as kiwiberry at that time, It was being sold as an ornamental plant. However, we have, records from the 1890s of people, praising its quality as a fruit, it was widely distributed and swapped among garden clubs and horticultural societies with hints about how to make jams and jellies and to use the fruit.
So people, it wasn't that people didn't know That it had a nice fruit, but it seemed that the, at least the first probably 30, 40 years, the plant was really thought of as an ornamental vine.
[00:07:22] Pruning Techniques for Kiwi Vines
So we have a couple of emails already. The first one is from Aaron. Aaron writes, I have two female and one male kiwi vine.
How much should I prune them every year?
A lot. And this is, one of the things that took me a while to get comfortable with, these vines is you have to prune them like you mean them. and the reason for that is, is that, in general, it's going to bear fruit on year old wood. Out in our vineyard right now we're seeing fruit being produced on growth that happened last year in 2021.
At the end of this year, once we harvested all of our fruit. What you need to do is cut away all the fruiting laterals from this year, leaving only the growth that happened this season. So a true, intensive management of the canopy is almost a complete canopy replacement every year.
And if you don't do that, what you find is that the canopy sort of gets larger and larger, but fruit is only happening on last year's growth. So the overall fruit load to volume of canopy goes down quite a bit. So vines that are left in a more ornamental setting where that pruning doesn't happen, what you'll find is this, it's actually quite hard to find flowers and fruit on those vines.
so it's very, hard, hard pruning. And I, would, direct anyone, For some of the specifics on, pruning, we put together a very detailed production guide, and it was geared toward commercial growers, but it certainly is applicable for home gardeners as well. And that's at, www.
noreastkiwiberries. com. Noreast Kiwiberries, all one word. And we go to a lot of, explanation about how to prune.
Oh, that's fantastic. And I'll include a link, in the show notes for this show as well for that. So that's great. So just to clarify, when you say you prune a lot, you prune a lot, but once a year, and that is after fruiting.
You've harvested the fruit, you're removing, the fruiting laterals that had fruit on them. You're essentially removing all this year's growth and letting it start again next year. Is that true?
Yeah, So, It gets technical, not technical, but we have to get into the weeds a little bit here, because all kiwifruit, species are dioecious, so as, Aaron said, there are male and female plants.
There's also very different pruning requirements for males and females. So males are very easy, but so we'll talk about males first. Male plants that you have, you want to prune as though they are ornamental vines. In other words, they're going to have a flush of flowers, probably, will probably open up in early to mid June.
As soon as flowering is done, and you'll see this because the flowers will turn brown, petals will drop, you can go in immediately and prune out all the wood that was sustaining those flowers. And it's going to look horrendous. It's almost, I would say, an 80 percent of the canopy you're going to remove.
So before and after picture of a male vine that is properly pruned for production, it, you have to have a strong stomach to look at it. It is a lot, it is a lot of, material is pulled off, What you have to remember is that you still have the rest of June, all of July, all of August, and all of September for the male to regrow.
And it's that flush of growth that will then flower the next year. So that pruning, that hard pruning happens right after flowering for males. For females, obviously, you don't want to prune right after flowering because you need to wait for the fruit to develop. So for females, what you would do is go ahead and maintain all of that fruiting wood, obviously, throughout the season.
deal with the harvest. And then once the plant goes dormant, and usually we suggest, January, February, then you go in and prune out that old fruiting wood. And if you've done things correctly, there's enough replacement growth from that previous season that you can then lay down And in the place of the wood that you're removing, and that's what achieves that full canopy replacement every year.
Beautiful. Okay, wonderfully clear. Let's go to the next question. this is a good question from Florence. Florence says, Hello, Susan. Is the plural of kiwifruit pronounced kiwi or kiwis?
Oh, wow. Florence, that's a great question. It's easy for me because I can say Kiwiberries, and I know that's the plural, and so I can, maybe dodge the bullet a little bit there.
But if you're working with them, if you're working with the fuzzy kiwis, to be safe, I would call them kiwifruits, maybe, and that way you know that you're know that you're safe.
Okay, so we talked a little bit about the history and I think it's interesting because it's a much longer history than I ever imagined.
Because for me when I see kiwifruits in the supermarket, I think I remember in my childhood when I first saw a kiwifruit. Like I don't think I grew up with them. did they get lost somehow through history? How come we didn't know about them?
Yeah, the kiwifruit is, so we'll talk about fuzzies, the fuzzy kiwis for a second.
Currently today, the fuzzy kiwifruit industry globally is about a 3. 3 billion dollar industry. And, but fuzzy kiwifruit did not become a globally traded commodity until about the 1970s. Of all of the, of all of the fruits in our food system, I think one can make a pretty sound argument that the fuzzy kiwifruit is the most recently domesticated fruit of any significance in our global food system.
So if you look at all throughout Human history, all the work that's done to domesticate plants and breed plants. The fuzzy kiwifruit is almost our most recent example of something that's broken through and is now traded on a wide scale. For thousands and thousands of years, Kiwiberries and many of Actinidia species, have been essentially wild harvested and foraged in many parts of China.
And I think because of the availability of that, there hasn't been that same focus on turning them into a commercial crop, but that's changing, a lot. Since about 2019, global kiwiberry acreage, commercial acreage, has almost tripled to the tune that there's now about It's hard to get real numbers, but probably 4 500 acres of commercial kiwiberry production in the world right now, whereas in 2019, there was only about 1, 000. Because it's an exciting time to work in, my interest broadly is in neglected, Crops, underutilized crops, orphaned crops that have great potential for our food system. And the kiwiberry is, one of those. It has proven commercial viability and yet it has just lacked that systematic effort to work out the kinks of its production and, then champion it into the food system.
Okay, couple more emails. We've got one here from Kelly. Kelly says, Hello, Susan. Interesting show today. Are kiwi plants or vines safe for pets if they eat them? And Kelly is listening in Orlando, Florida.
Kelly, that's a great question. and, the reason I say that, there was a famous, the, probably, the archetypal plant germplasm explorer in the U.
S., David Fairchild, back in the early 1900s, who led a lot of plant exploration trips, during that era. David Fairchild had a great article in the journal Science. Back around 1910, I can't remember the, name, or the year exactly, but the name of the article was Cats as Plant Explorers. And what he found was he had a greenhouse full of different Actinidia species growing, and what he found is his cat got into the greenhouse and preferentially destroyed, absolutely shredded and destroyed Actinidia polygama, which is also called silver vine.
And that led to some really interesting research, but basically Actinidia polygama is a feline stimulant. So whereas here in North America, If you want to treat your cat, you would give your cat a little pillow or a sachet of catnip. In Asian countries and in China, the feline stimulant of choice is silvervine.
And it has, it is not the same compound as catnip, and I looked into this a little bit, it turns out that Only about half of cats are stimulated by catnip, but the compound in silver vine stimulates a far greater percentage of cats, and so I give that to my cat. When I've pulled out a vine, I'm moving things around because we transplant vines in and out all the time at the vineyard.
My cat will just roll in the root ball and chew on the leaves and is very happy with it. So I know that silver vine has some, compounds that cats really like. I don't know of any, toxicity issues, with animals. So I, can't say with certainty, but I, have never run across anything like that.
At least in the species I work with, but there's huge diversity within the genus.
Okay, so we have a question from Jessica. Hi, Jessica from Southern Colorado here. So Jessica is going straight to the really important stuff.
[00:17:27] Pests and Diseases of Kiwi Plants
And she writes, what are common pests or diseases we should look for? Thank you.
That's a great question, Jessica. as with a lot of cropped plants that are not planted yet on, commercial acreage, there always seems to be a honeymoon period where there's not a lot of pests and disease that affect it. And that's what we've seen at our research vineyard here.
we have a completely no spray operation in our vineyard. The only pest of concern that I've seen is every now and then we'll get a spate of Japanese beetle coming through the vineyard. That largely does damage to the foliage of the plants, but like I said, these are plants that often you're pruning off 50 to 80 percent of the canopy anyway, so they can really sustain.
that damage to the foliage. I was really worried about it the first few years. I was hand picking bugs off of vines and I realized over the first couple seasons that it didn't really matter. so I've seen damage from Japanese beetles. Sometimes they'll damage the fruit, but it's usually a very, small percentage of the fruit.
and so it's not really an, issue. We see some cosmetic issues on the fruit. Sometimes we see flyspeck, which is similar to what on apples, but it's a completely superficial visual thing. It doesn't affect fruit quality at all. We also see some sooty blotch, which is also cosmetic and doesn't really affect, eating quality.
But if you're, say a market gardener, you might be concerned about those. What we see, though, in the breeding program is that different varieties are variously susceptible to those diseases. We'll have some that are just, really look dirty, because of those cosmetic issues, and others are quite pristine in the same environment.
So we're trying to push, selections towards appearance in that way. yeah, so we haven't, seen, fingers crossed and knocking on wood, we haven't seen really big issues. There's, a bacterial canker, Pseudomonas syringae Actinidia, that has affected every kiwi production region in the world, except for North America.
And we, at least in the U. S., we're under quarantine. We can't import Actinidia germplasm from anywhere in the world because of bacterial canker concerns. So we haven't seen that in our vineyards, and kiwiberry as a species is less susceptible to it than the fuzzies anyway.
here, I have a question here from, let's see, from Sam.
Sam says, Hello, Susan, your guest has a very unique first name. What is the history behind that? Thanks. Love you in Toronto, Ontario.
Sam, great question. Iago is a, form of Jacob, Iago. And it shows up in a couple different cultures. It shows up in Welsh. It also shows up in Spanish. Sometimes we think of Santiago, Chile.
And my pedigree, I'm pretty much a European mutt, so I'm not sure exactly how it got to me, but, through the family tree somehow.
Nice. Okay, now we had, there was quite a discussion on Facebook before the show. And I got this fantastic email from Elizabeth from North Carolina. So here's what Elizabeth writes.
Hi Susan, I grow kiwi and I love the fruit. But I'm just learning about the invasive potential of hardy kiwi. You have to admit they're pretty darn vigorous. So I guess it makes sense. It turns out the seeds can germinate and animals are suspected of spreading the plants. U M N shows germination in their preliminary work.
it has escaped and is causing damage in New England and New York. says Elizabeth, I will definitely keep an eye on my area in North Carolina, but I will also consider removing the plants. We don't need another invasive vine in North America. wow, that's, a big concern. how do you feel about that?
[00:21:47] Invasive Potential of Hardy Kiwi
Yeah, so we could have a whole hour on this. certainly, I'll try to be succinct in my response. First, of all, as a researcher who's fundamentally interested, not only in our food system, but in preserving our natural resources, I would not ever promote a species that has invasive risk to it.
And so my research, and I've done a looked into this a lot. And again, with Bob Guthrie over the last 10 years, we've spent a lot of time really looking at this allegation. Of invasiveness, and there's a great deal of misinformation out there. we are in the age of information circulating on the Internet.
it's very easy to make an allegation, and then once it's out there, it's extremely difficult to bring evidence, of the alternate explanation. But here's what we know. as you said, for many folks, Kiwis and certainly kiwiberry seems like a new crop. It's a sort of a new species and we assume if something's new to us that it's new in general.
I often have people come up to me and say, Oh, Kiwi, what is that? Some weird new hybrid between fruits. and so to understand that it's just another species been around for thousands of years. But specifically in our region, the history of it in our region is really important. It has been here for 150 years.
In our region, and I think what we have a hard time appreciating now is that in those early decades, this was a plan that was widely distributed. thousands of plants. We have records of seed being sold by the pound. And I just counted up some seeds in the lab here today. A pound of kiwiberry seed has about almost 400, 000 seeds in it.
And we had seed being sold by the pound. We have records of this being, Used by landscape architects, Frederick Law Olmsted, the father of landscape architecture, used this vine very commonly in his plantings, as did many of his disciples, Beatrix Ferrand. It was a common plant in all of the biggest states, going back to the 1900s, 1910s, and so on.
So first, the first thing we have to wrap our minds around is the deep history of this plant in our region. This isn't a new plant. if you see a naturalized plant, it is not necessarily the case that it has recently introduced and this is an explosive first step toward an apocalypse in which it takes over the forest.
So all that being said, I think it's worth talking about one of the sites in particular, your caller. Your caller mentioned, that there are evidence of escaped sites in New England and New York. And let's talk about, let's talk about that. The, sort of flagship example that is held up by folks who are alleging invasive risk of the species is Kennedy Park.
In Lenox and Massachusetts and in the Berkshires. And what happens is that is now a park and it's actually beside another, an Audubon sanctuary right now. And so if you're a hiker walking through the woods there, you've entered a place that says this is a park. This is a sanctuary, you would be forgiven and thinking that you're walking into some natural pristine area.
And so on those trails, when you come across an acre scale amphitheater of kiwi vine that looks, for all intents and purposes, like kudzu, you could understand being panicked about that. That this is really a problem that needs to be solved. The problem with that interpretation is, however, is that even though these places are parks now, and are sanctuaries now, if you go back to the 1940s, these areas were clear cut.
And the vines that were planted, we have documentation of estates, either in or directly bordering these sites, where we know they planted them in the gardens there. the members, the owners of those states were very involved in garden societies, and the, the Lennox, Garden Club was the first owner of the Audubon Sanctuary.
And so we have, we know that the vine was planted heavily in these regions prior, at a time when the area was clear cut, and at a time when cattle was very, was very present there as well. So now fast forward. 100 years, 120 years, and you see a localized, naturalized population of kiwiberry vine. The question you have to ask is how did it get there.
And all of our evidence suggests that the vines themselves are older than the forest they're supposedly invading. And this is part of the problem and there are other sites, canoe meadows, Coffin Woods, Comstead Park, you can go to Long Island, you can go in Maine, there are various sites and what we find in every case where we actually do the work.
And we actually dig into the land use history is that we find there was major forest disturbance. And records of vines being planted at that time. Now, a hundred years later, we see a big naturalized population. Without the context of that history, you would conclude that there is a real problem here. But here's the thing.
We know it was widely, planted. And so the question is, if this is really an invasive species, Where is it? It is at a few, a handful of sites where we know there was major disturbance and clear cut and often with cattle. there's research coming out of Japan that's suggesting that its active dung beetle populations are the third needed ingredient in order to establish kiwiberry seedlings.
If you go up to George Dorr's, Mount Desert Island Nursery, where we know he planted kiwiberry mother plants back in the 1880s. Those plants are still there. We've gone there. They've trunks on them that are eight inches in diameter. You look around the woods there, there are not seedlings, and it's not because of an absence of frugivores.
There's all kinds of raccoons and possums and animals that love fruit. There's birds everywhere. And the question is where, are the vines? An analogy for me, and I know I said I was going to be brief here, but this is really important because the way our invasive regulation system works right now is it's very easy to allege invasiveness.
And specifically, if you're alleging it about a plant, That is underutilized and doesn't really have, stakeholders already there's no one to bring the other side of the story. And if you wanted to take a complete zero risk approach to our environment, it's much easier just to prohibit things.
But for those of us who recognize that the future of our food system lies in a strategic integration of new biodiversity as we deal with things like climate change and nutritional security and all that, we need to be smart about diversifying our food system. A sort of blank check writing off of plants without evidence is cutting off options to growers, it's cutting off options to consumers as well.
So it's not that there are really invasive species out there. Absolutely. one of them, for example, is Oriental Bittersweet. And the Oriental Bittersweet example is really telling. if you look at Oriental Bittersweet and Kiwiberry, just gross morphology, they look very similar. They were actually both brought to the U.
S. the same year. They were both brought to the U. S. in 1877. Kiwiberry appears to have been much more widely disseminated. But if you look at the maps of naturalized populations of oriental bittersweet versus kiwiberry today, oriental bittersweet is in every county east of the Mississippi. it is taken over like wildfire.
Where's kiwiberry? Over and over again, it's at the few places where there was an estate, there was a massive land, disturbance. And these populations haven't moved. Over 150 years, Maybe they've moved a quarter mile, a half a mile. This is not the great jumping of spatial gaps and invading healthy forest that would meaningfully warrant a label of invasiveness.
Wow, so that's a lot of information and thank you so much for answering that amazing question. I really appreciate the question from Elizabeth.
[00:31:07] Exploring Kiwi Wine and Other Uses
So Iago, we've got a couple of quick questions I want to go through. one of them is from All Other, is the only name on here, All Other. hello to Susan Poizner from Ottawa, Ontario.
Does your guest have any recipes for kiwi wine? And I guess my question is, there such a thing as kiwi wine?
There absolutely is such a thing as Kiwi wine. I personally do not have recipes, but we have some wineries here in New Hampshire that have been making Kiwi wine for 30 years. Hermit Woods Winery is one that comes to mind and, they make it and they can't keep it on the shelf.
People love it.
Is it a mix of grapes and kiwis? Is that what it is? No,
no.
[00:31:51] Kiwiberry Uses and Benefits
so what's, nice about kiwiberry, it's one of the few fruits that have sugar levels that are on par with wine grapes. Our, if you get a fuzzy kiwifruit in the store, you will be lucky if it's, 7 to 8 percent sugar, a kiwiberry, at least grown in our region is routinely 20 to 25 percent sugar.
So that's, getting into, wine grape territory. And it also has a real nice complexity of flavors, a nice acid balance, a lot of tropical flavors. So winemakers. Love it. we also have breweries here using kiwiberry, cideries, different distilleries use it as an ingredient. and it makes amazing jams and jellies and fruit leathers.
And it's also a great thing to use as a savory marinade for meats because, kiwiberry has a proteinase in it called actinidain that acts as a meat tenderizer. So in the same way that you might use pineapple juice to tenderize your meat in a marinade, you could substitute it with kiwiberries.
Now, I have not tried a kiwiberry before.
You got to send me some at some point because I don't grow it yet.
I just got two doors down the hall. I have about 500 varieties from our research vineyard, berries laid out that I've been eating. I was actually making sure I didn't have kiwi seeds in my teeth. So I wish you were here because I
would give you more
than you would know to do it.
So do snackers really like Kiwiberries just like fresh? Is that you could just gobble them up fresh? Yeah,
absolutely. And what's wonderful about it is, kids really love them. because they're this tiny little, they're very cute. They're very cute little things. They have this little hair at the bottom, which is the, the remainder of the stigma at the bottom, it looks like an eyelash and you just pop it in your mouth like a grape.
And and the nutritional profile is off the charts, so it's this very nutrient dense food that is extremely yummy. like I said, 20 some percent sugar, but also great, like grapefruit level acidity. And so you have this really nice citrusy, complex balance to it. And, yeah, the hope is, and for some varieties you can certainly just keep eating them, many breeding lines in our vineyard taste horrible.
and so this is part of the breeding process too. I would say out of every 100 breeding lines that I screen, maybe two or three are worth eating. So this is a lot of the work that we're doing here is trying to find what are the fruit profiles that are really going to be successful in the marketplace.
we've got a question here from Sean, who asks about color. Hi, Urban Forestry Radio Show. Are, all kiwifruits a green color, in the inside flesh?
No, and they aren't. there's really spectacular examples of color, like silvervine actinid polygama is this bright hunter orange.
And if you cut it open on the inside, there's an orange, it's orangey red flesh on the inside, and it tastes like a I don't know how to describe the taste. It's skunky. I can see it maybe in a savory chutney. as far as Kiwiberries go, there is variation. We have red fleshed Kiwiberries.
We have green fleshed Kiwiberries. We have green ones with sort of red blushing to them. Some of the ones coming out of my vineyard are almost a deep purple color in the skin. And flesh color varies as well. Here in my program, I only see greens. but it goes from dark green to very, light, almost yellowish tinge.
And we have some red flesh varieties as well. If you go to China, if you go to the seat of genetic diversity, there's, a lot more colors.
We got a question from Monique here. That's interesting. Hello, Susan and Iago. Is kiwifruit good for diabetics to eat or is the fruit too sugary?
I have no idea about that's a great that is a great question.
Yeah. I would imagine there's nothing. There's nothing about the Kiwi sugar profile that I think would make it somehow unique compared to other fruits. So I would say, whatever the best practices is of diabetics around, fruits in general and, think of, think of grapes, for example, or other sugary fruits.
I would imagine the same precautions would be taken around Kiwiberries as well.
Yeah. Okay.
[00:36:28] Growing and Pruning Kiwiberries
So I'm sure that a lot of people listening to this show, some people actually grow Kiwiberries already. Some of us. and a lot of folks like me are thinking, wow, this would be a great thing to grow. let's talk, we talked about cross pollination.
So it sounds like you need a couple of plants, the male plant and at least one female plant. you talked about pruning. Pruning is a big part of the care. Does it need to be grown on a trellis? or, yeah, what are the options there?
Absolutely. And this is where I feel like I've gotten in under the radar.
This is a show about fruit trees. And of course, Kiwi. Kiwis aren't trees. they are, they're perennial woody vines, but I love hanging out with the fruit tree folks. But because they're vines, they need structure to them. And, a mistake would be to plant it by a tree and let it run up a tree.
That, that's exactly what you don't want to do.
Why? What would happen? Because the permaculture folks would love to do that kind of thing. What's the problem?
And the problem with that is that the canopy, two problems really. The first is just from a fruit production standpoint. As soon as you have a canopy going 30 feet up into a tree, you simply can't get to it and prune it the way it needs to be pruned in order to stimulate fruit production.
So if your interest is in fruit, you need to train these things in a way that you can intensively manage the canopy. The other thing, and this harkens back to the invasive discussion, I think moving forward with this species, knowing people's concerns around it, you want to trellis it and you want to maintain the canopy.
And when you're done with the vine, remove it. so that we don't have this issue a hundred years from now of a persistent vine being mistaken for an invasive.
And can they be dug out completely quite easily?
Oh yeah, absolutely. Kiwiberries have a very shallow root system, almost all kiwifruit does, and we know from folks trying to eradicate naturalized vines in areas like Kennedy Park where the use of that land has changed from an estate to a park.
There's been a lot of work eradicating vines and what we know from that work is that kiwiberry vines succumb very easily to a stump and glyphosate treatment. So they are, they are not pernicious in that way. They're, easy to kill.
Okay.
[00:38:59] Overwintering and Cultivar Selection
So we got a question here from Jessica. Jessica writes one more question.
What's the best way to overwinter vines? Should I transport transplant potted vines directly to the ground for this fall? Or should I wait until they're dormant in the spring? Thank you for all the excellent information.
Absolutely. It's a great, it's a great question. I have learned over time here that my success rate and establishment and getting a vine through its first winter, it's better to plant in the spring.
what we generally do is we keep vines in a protected area, they go ahead and leaf out, and then once we're past first frost, We would go ahead and transplant the vines into the ground. That being said, I talked to growers, I talked to folks in the nursery trade, who also do perfectly well planting vines in the fall.
so here it would be as long as you got them in the ground by early September. But if you do that, you might want to take a little bit of precaution, maybe mulch them with a good six inch layer of mulch or put down some agricultural fabric over top of the vine, just to get it through its first winter, because there's a question about whether or not it has sufficiently established and hardened off.
but if you can wait. I would say your better bet is to put them in the spring.
We've got another question from Aaron. And Aaron's helping us to get into the, domain of cultivars. So Aaron asks, Hello, another question. Are there any varieties of the colored kiwifruit that are hardy to zone for?
Thanks, Aaron, from Lac Saint Marie, Quebec.
Not
of the varieties. that I have access to, again, on North America, because we're there's been a lot of work on this done in Europe, and they have varieties there that we don't have, but of varieties accessible to us, I don't know of any red fleshed varieties that I would feel Confident would be hardy to zone for that being said, the proof is in the pudding.
if that's where you are, and that's the plant you want, it's worth giving it a shot to see because you may be in a microclimate there. It may work.
and how many cultivars are there? Is there a wide selection of tasty cultivars that you'd want to grow?
Yummy ones. That's such a great question.
My, my first four years of research into this crop was all around trying to sort out the mixed, up genetics that have occurred over the last 150 years of plants being moved around by people and companies and collectors. And so the USDA, for example, at the time I started had a kiwiberry collection of about 160.
varieties, we'll say, 160 accessions. I got them all here in New Hampshire and I started using genetic fingerprinting methods that we were developing here in my lab just to try to sort things out. Who's related to who? Where are they coming from? And what we found through that exercise is out of the 160 or so putative different varieties.
We really only had about 50 unique lines. The rest were the same vine under different names, for the same vine. It was just a complete mess. And so sorting through all that, what we found is that we have far less diversity than we thought we had. Within that group, the variety I recommend for our region here in New England, and I would say this would probably apply to listeners in Southeast Canada as well, is a variety called Geneva 3.
And Geneva 3 was a selection, at the Geneva Experiment Station in New York in the 1960s by George Slate. And it has just exceptional eating quality, storage, qualities. It yields very well, and so that's the one I recommend for, growers around here. There's another, widely grown variety called Ananasnaia.
which is a Russian, word meaning little pineapple, but Ananasnaya, was originally brought to the U. S. via Belgium, around 1915, I believe. What's funny is it was originally brought in as a different species, Actinidia coelomycta, and if you look at the USDA collection, there's no fewer than six or seven.
Different Ananasnayas, some are male, some are female, some are kolomikta, some are Arguda, and it's just a glimpse into the confusion that has happened, but Ananasnaya is the core commercial variety in the Pacific Northwest. So if you go out to Oregon and Washington, those folks are growing Ananasnaya.
What we find here in this region is, that Ananasnaya is a little bit variable, in my opinion, in terms of fruit quality. it can have real cosmetic issues some years and the other real problem is that it's pretty late In maturing, it come, it ripens about two weeks later than Geneva 3, and for us that starts getting into danger of frost territory.
I, there was so much wonderful conversation on Facebook and I wish I could share all the comments, but I want to share a couple of them. One comes from Michael. So Michael is in Quebec, and Michael grows miniature kiwi plants, I guess for sale. So Michael writes, here in Canada, zone 4b, There is a lot of potential for hardy Kiwis.
I am now with 70 different varieties and every year I'm getting new fruits. Now I'm, I think Michael may be selling the plants or maybe he's selling the fruit. but miniature Kiwi plants, what does that even mean?
I don't know what that means. I would interpret that as. It's miniature kiwis. It's plants of miniature kiwis rather than miniature kiwi plants.
Oh, Kiwiberries. It's the berries rather than the plants. I would
assume he's referring to Kiwiberries there. Yes. And from the description, it sounds like maybe he's doing a little bit of work of just planting by seed and seeing what kind of variation he's getting. And so that's doing some breeding work.
And Michael, I would love to talk with you about what you're seeing there. for your, probably average listener, I would not recommend growing plants from seed, because, as I said before, a very small percentage of those plants, first of all, more than half the plants are going to be male, if you do that.
which is a waste of your time and energy, and even of the females, maybe one to two percent may have fruit that's worth eating. if you are a backyard gardener or just want to put a few vines in the ground, definitely source known cultivars rather than try to do something from seed. you'll waste a lot of time and energy growing from seed.
Then I've got a comment here from Tina. Now, a lot of the people on Facebook said, look, I love this fruit. This is amazing. I'm having so much fun with it. Tina said, I have two issues with them. The birds remove them before they are ripe. And those that they don't. that they leave don't ripen reliably before our first frost.
They are very frost sensitive, i. e. the leaves die quickly after a night at or below 32 degrees Fahrenheit. The fruit is delicious when ripe and there is some success ripening them indoors after picking them. before the threatened frost. and Tina says, I have not found them invasive here. Getting them through their first winters is a challenge.
Also says Tina, woodchucks love them and attack from a ground above and below ground.
Oh gosh.
Thank you, Tina, for all these little points. So I don't, we've only got a few minutes, but let's say in, There's a lot in there, but let's say two minutes. let's talk about a little bit.
[00:47:25] Harvesting and Storage Tips
Sure, so the harvest question, it's, so kiwi, kiwifruits are climacteric fruits.
And what that means is that they can ripen off of the plant because they produce their own ethylene. So the, way you should harvest a kiwiberry vine, and if you go to our website we talk about this in detail, but basically you want to pick the fruits when they're at about eight brix, eight brix, eight percent sugar, and you would do this with a very cheap handheld refractometer, just squeeze some juice on it and read the sugar level.
At eight brix, These are rock hard fruits that are absolutely disgusting to eat. If you cut them open, it's very latex y. These are fruits that birds don't touch, animals don't touch, it is well before you get into any danger at all. Harvest everything at eight brix. bring them inside, you can then store them in a cold, in cold storage for at least six weeks, and then when you want to ripen them, just bring them out of cold storage at room temperature, and they will ripen over a period of five, six, seven, eight days.
so this is, how, you should approach harvest on the thing, and it does a lot of things for you. It gets out of the field before frost, it gets out of the field before things like spotted wing drosophila and fruit fly issues. And so you can really, compared to other soft fruits, raspberries and strawberries, being able to get these fruits out of the field early, is a big advantage.
And we've done a lot of research here. We've looked at ripening characteristics of fruit on a vine versus fruit pulled at eight brix and ripened indoors. You have no benefit in terms of sugar levels that are achieved. and so it's only, there's only bad things happen by leaving them on for too long.
Also, harvest becomes much more difficult because harvesting soft fruit is a nightmare.
this is really exciting. I have, in my own backyard, not in our community orchard, I have a bed where we had crown root gall, sadly, with our apple trees. It's so, tragic. And I'm thinking, hey, I've got the trellis.
Maybe I, wonder, if the Kiwi plants would survive, I, I don't think they're vulnerable to crown root gall. Is that correct?
There is some susceptibility to, Phytophthora and Kiwis. The main thing is that Kiwis don't like their feet really wet. So you do not want to plant them in a saturated soil, where they're going to be very saturated for days on, on end.
But as long as you don't have those water issues, you shouldn't have a problem. As far as groundhogs or woodchucks, I don't know what to tell you. I, we have a nice research station where things are fenced off, and I guess we have a big enough planting. that I haven't seen that kind of damage, but I don't know if trunk guards would help in, that kind of situation.
Yeah, it might be worth a try. where did the time go?
[00:50:23] Show Wrap-up and Resources
I feel like we've just warmed up and got started and there's a lot more we could discuss, but first, I want to say hello to some of the regular listeners who sent me emails this month.
So this month, Hank, Jane, and Gail all wrote to send the Orchard People team best wishes for Canadian Thanksgiving. And for those of you in the States, you might not know that Canadian Thanksgiving takes place on the second Monday in October, so I really appreciate that. And other listeners had questions.
we were talking, Iago, you mentioned the refractometer and we talked about that with the expert guests. Amy wrote to ask how to order my books because she's going to be giving them to her gardener friends for Christmas this year, which was lovely.
And of course, I love it when I get jokes from listeners. So here is a joke. From Andy. Okay, it's a warning for gardeners. Iago, you should keep this in mind as well. Okay, this is the warning. Be careful what you do in the garden. The potatoes have eyes. The corn has ears, and the beans talk. Okay, thank you for that, Andy.
I needed, Gary in the studio. You forgot to do your baboom.
I want to tell you because I know you like jokes. I actually got another joke from Tim, on the similar vein. Should I tell it to you, Gary?
Because I know you're a joking kind of guy. Okay. So Tim writes, and this is funny that I got them days apart. Tim writes, my friend Jack claims that he can communicate with vegetables. Jack and the beans. Thank
you. We'll be here all week. Check out the veal.
I want to thank Iago for coming on the show. Boy, this is a big topic, and I think we got, we dug our teeth into it pretty nicely. I think we got, Good stuff.
I think there's lots more to learn. What's your website, Iago, where people can learn more about you and what you do?
Absolutely, yeah. Our online production guide, it's NorEast, N O R E A S T, Kiwiberries. All one word. NorEastKiwiBerries. com. And, there are details about everything from site selection, to trellis construction, to pruning, to harvesting, post harvest management, and everything.
So that would be if you want to grow these things. That would be a good first place. and we've tried to bring as much reliable information into one place for folks who are interested in exploring this, crop.
Great! And I'm going to be working with Iago as always after the show. I like to put together a video, shortened excerpt.
It's a video version, so I'll get some pictures from Iago and we'll put together a little video so you can see what we're talking about. So that's all for the show today. Oh my goodness. If you want to listen to it again or download other episodes, all you have to do is go to orchardpeople. com slash podcasts and you can learn more about growing fruit trees on orchardpeople.
com Where I have detailed articles and more courses on fruit tree care. Finally, if you want to learn to grow fruit trees, but you don't have a lot of time, grab a copy of my new book, grow fruit trees fast, and you can read the book in just an hour to purchase your copy. Just go to orchardpeople. com grow fruit, or you can search.
Grow fruit trees fast in your local Amazon store. And that's all for now from me Susan Poizner in the studio and from Iago. You want to say goodbye to everybody?
Just goodbye. And thank you so much for the opportunity
Okay, I hope you guys will all join me again next month where we're going to talk about another great topic And I will see you then.
Thanks everybody for tuning in and goodbye for now.