Share your heartnut experiences on this thread.

Grafting heartnuts requires a lot of heat. Wait till you know for certain you’re at 75 F / 24 C and then do it. You want the forecast to stay at/above those temps. As a skilled grafter you will get the best number of successful grafts using the 3-flap or 4-flap aka “Banana Graft” method, or, the bark graft method & 50% is on a great year.

As a rootstock, black walnut is commonly used and I recommend it, but also seedling heartnut should be explored. Try not using Carpathian/Persian/English/Juglans regia (seedling rootstock) due to its inability of continuing growth sometime mid-summer-ish/later. The same thing that Shagbark hickory does btw, which will impact nut size and kernel /size maturity at harvest, annually.

These are my notes from Fall 2019 on cultivars. Only two not-named (yet) cultivars held their sweet and smooth flavor after two months of open air drying. One is a seedling of ‘Stealth’ named ‘Killdeer’ for the speckles on the husk that reminded him of Killdeer bird eggs and the shape of the husk to a Killdeer’s egg; and the other ‘Pearl’.

You will find Killdeer for sale upcoming from Grimo Nut Tree Nursery. I’m not sure the future of Pearl.

Heartnut: Juglans ailantifolia var. cordiformis ‘Killdeer’ (Origin: Fred Blankenship. USA. Seedling of ‘Stealth’)

Heartnut: Julans ailantifolia var. cordiformis ‘Pearl’ (Origin: Fred Blankenship. USA. Improved Seed)

Heartnut: Juglans ailantifolia var. cordiformis 'Simcoe’

Time after time Simcoe did not crack well when tapped side to side along the suture with a mason’s hammer. Heartnuts will make a popping sound when the seam separates and you can easily open them with a fingernail or pocket knife.

Simcoe heartnut

Simcoe heartnut

Simcoe heartnut

Heartnut: Juglans ailantifolia var. cordiformis 'Locket’

Heartnut: Juglans ailantifolia var. cordiformis 'Adelphia’

I had a lot of problems with Adelphia. It’s a poor cracker.

Heartnut: Juglans ailantifolia var. cordiformis 'Adelphia’

Heartnut: Juglans ailantifolia var. cordiformis 'Adelphia’

Heartnut Evaluation 2019

Killdeer 11-14-2019 from 9-19-2019 (period dried)

Kernel: light tan/white

Flavor: excellent, smooth.

Cracking: A

Kernel Extraction: A

Pearl 11-14-2019 from 9-19-2019 (period dried)

Flavor: a bit sweeter than Killdeer. doesn’t have the black walnut taste of ‘Locket’.

Kernel: light tan/white

Cracking: A

Kernel Extraction: A

Locket 11-14-2019 from 9-19-2019 (period dried)

Flavor: not very good after 2-plus months dried.

Kernel: (1/2) got stuck and broke when tried prying

Flavor of 2nd nut tried: bland and not very good.

Adelphia 11-14-2019 from 9-19-2019 (period dried)

Flavor: held very little flavor but didn’t go toward astringent. Still, not something I’d want a 2nd of.

Cracking: F Fail 2 of 3

Kernels: doesn’t matter if won’t release. (shells shatter & break uneven)


Heartnut: Juglans ailantifolia var. cordiformis 'Stealth’

Heartnut: Juglans ailantifolia var. cordiformis 'Campbell CW-1’

Heartnut: Juglans ailantifolia var. cordiformis ‘Simcoe’ formerly 'Simcoe 8-2’

Heartnut: Juglans ailantifolia var. cordiformis 'Imshu’

Heartnut: Juglans ailantifolia var. cordiformis 'Imshu’

Heartnut: Juglans ailantifolia var. cordiformis 'Locket’

Heartnut: Juglans ailantifolia var. cordiformis 'Fodermaier’



I’ve just lost my one heartnut tree this year. It did not come out of dormancy (after 2 years of having done so). It was about 8 feet tall when it died. I had buds form, but don’t recall getting a look at them when they opened.

It was in a large pot as I don’t really have the room for it. (20 gal)

It was a Locket and I believe it was from burnt ridge. Replacing it will prove difficult as they are on a restricted list here in Michigan.

I purchased some whole nuts when I bought the tree and found them tasty.



I’ve heard recently that people were purchasing every heartnut Ernie Grimo was willing to sell and were using them for lumber plantings. I know nothing of heartnut lumber but I found the story of black walnut quite intriguing. The logs are put on ships destined for Germany and they’re spun producing veneer. The boat drops it off and turns around to come back again and get more. Apparently Germany makes a lot of walnut veneer furniture. I guess it’s safe to assume boards are made or logs are delivered too for producing hardwood furniture. Grimo raised his price soon thereafter as a matter of truth.

Someone on the East Coast with pretty significant acreage cannot grow enough at a price of 8$ a pound I too heard.

I haven’t researched any of this.



How would you describe the flavour of these and taste wise are they comparable to black walnut?


Great write up and comparisons, thanks!


does heartnut grow down your way Jesse?


I had two trees in that 20 gal pot. The heartnut and a Siberian Pea. I was concerned that the pea would succumb to juglone from the heartnut, but it doesn’t appear to have been a problem. the siberian pea has done well each year, so I suspect that lack of adequate water (or too much for that matter) was a factor in the demise of the heartnut.

I found the nuts to be milder than a black walnut (less bitterness).



Hi RichardRoundTree,

Most heartnuts taste nothing like black walnut and are their own flavor. They’re much more mild than black walnut and lack that bitterness (quite a lot or some have non bitterness.)

‘Locket’ heartnut tastes like black walnut.



Had several grafted and growing in the early 2000s, as well as some seedling heartnuts & Japanese walnuts(same species, but the nuts resemble our native butternut). Easter Big Freeze Disaster of 2007 killed all grafted hearnuts back to their BW rootstock except for ‘Late Rhodes’… several 8+ yr old seedlings were killed outright.
Have a seedling heartnut that bore its first crop this year, and a couple of seedling Japanese walnut trees in a CRP riparian bufferstrip planting that have been producing for a few years now.
The grafted Late Rhodes tree has never produced a nut, though it’s close to 20 yrs old… there are a couple of bearing age butternuts and a seedling of Bountiful (a butternutXJapanese walnut hybrid) growing nearby, but I don’t know if bloom periods are not overlapping sufficiently for them to pollenize the grafted heartnut, or what.

The few heartnut kernels I’ve sampled have been much milder than black walnut.
IDK about lumber quality of heartnut/Japanese walnut… probably comparable to butternut(aka white walnut)… but they’d probably require some pretty diligent pruning management… in my experience, J.ailantifolia tends toward an open, spreading habit not unlike apple trees in an orchard… none I’ve seen have a ‘timber’ type habit.


Aren’t heartnuts supposed to increase in flavor over a period of about a decade? Or at least that is what Tom Wahl told me. I figured they had very few unsaturated fats, but they don’t. Maybe they have a ton of antioxidants?



As much as I might like to know the goodness or badness of foods, I don’t look them up. I just figure that eating too many nuts will put a belly on me like a squirrel. That’s as far as my thought process goes, Drew.

I’m sure any tree can become better at what it’s doing as it ages but they can also decline. I’ve seen some old pecan grafts in a yard with excellent soil on the verge of dying (dead branches in the canopy and weak growth exhibited.) Without fertilizer those trees are gonna be gonners.

I’ve not read or heard anyone say that (any nut tree type) increases in flavor.




Does your seedling heartnut have heart-shaped nuts or the rounder looking ones that some pictures seem to show?



Oh, what I meant with the heartnuts was that they apparently age and increase in flavor once the nut has been harvested and put into storage. So if you store the nuts for about a decade they keep getting better. When I heard that I thought: “Nope. I am not patient enough for that.”


Are Heartnut as toxic to neighbouring trees and plants as walnuts are? I’d love one in the yard but all my fruit trees are all very closely planted so I wouldn’t want to risk harming them.

Do birds eat most the heartnuts in your own experience? Where I live, a lot and f fruit and nuts get lost to birds, mice and possums. Cherry orchards here are 100% caged.

Do you know if heartnut has a root system that can be extra damaging to buildings and pipes (like figs and mulberries are), or if they’re safer?

I’m really surprised to learn the different cultivars of heartnut just now (thanks!). Here in Australia I’ve only found one supplier- The Diggers Club- and they don’t mention the cultivar at all. I’d always assumed there’s just one since it’s so uncommon.


I think it might…though I havent found any examples mid state, there are some on the coast. I want to trial some here and have planted out some seed


Is there a pollination chart somewhere . I have a Stark Brothers Westfield heartnut . I get few nuts due to poor overlap of its flowers . Bountiful butternut is not a pollinator due to the heartnut being done before Bountiful blooms . No mater what Stark Bros claimed .


There are so many heartnuts on the ground that “no” birds do not eat very many. As to juglone, the toxin given off of the entire Genus: Juglans, yes I would treat heartnuts as you would all trees related to the one most commonly thought of when toxin questions come up: Juglans nigra, black walnut. I can’t tell you about their roots but I wouldn’t plant one within 10’ of my own driveway or sidewalk and I certainly wouldn’t plant any tree within’ 20’ of my home. You can take that to the bank.

Two hearnuts are needed or a butternut or buartnut to pollinate. Hope this helps everyone.


I have 3 heartnut trees purchased from John Gordon in 2006. They are seedlings from CW3. I also have 3 heartnut trees grown from seed he gave me. None of those trees are good timber form trees. They have a short trunk (3-5 feet). I have about 10 younger seedling that I may try to prune to see if they can be pruned to assume a better timber form. They have a very different root system than black walnuts. They have many large roots near the surface that radiate out. I suggest anyone interested in growing heartnuts buy grafted trees or graft from know cultivars. Only one of my seedling trees produces a decent locket shaped nut.


Thanks Barkslip, i’ll stick to easier trees for now and if I ever own a large property I’ll plant the juglans trees in their own area (walnut, heartnut, pecan, hickory, butternut).


@Fusion_power to how damaging an extent does the juglone produced from pecan and/or hickory affect plants known for intolerance?