Heartnuts are also known as the Japanese walnut (Juglans ailantifolia var. cordiformis) although they are really a sport of the normal oval shaped nuts. The cultivated varieties have a heart shaped nut that cracks open on the edge and have been selected for flavour, cracking quality and productivity.
Heartnuts are considered hardier (for winter cold) than English walnuts (Juglans regia) and are more resistant to walnut blight, they do however all come into leaf in April to very early May so are suspectible to later spring frosts, they should be considered similar to early/mid season English walnuts. Even though they are often partly self-fertile it’s better to plant two or more cultivars to help pollinisation. They need full sun and well-drained soil and in the first few years concentrate on putting down a long taproot.
During winter it is worth using fleece to protect the grafted area of the tree for the first few years. Trees can grow to 10-15 m in height and width so space at 10-12m.
| Variety | Description | Availability | |
|---|---|---|---|
| Adelphia | US variety from Rutgers' research farm. Large love heart shaped nut, ripens later than CW1 and Imshu. Excellent cracking quality. Protandrous (male flowers before female) | TBA summer 2024 | |
| Campbell CW1 | Canadian Heartnut that produces a good crop of medium/large nuts, partly self-fertile, late pollinator. |  | TBA summer 2024 |
| Campbell CW3 | A heavy producer of medium sized nuts on a more compact tree. The nuts will crack out a mixture of halves and whole meats that drop out of the shell freely. It is an early pollinizer. |  | TBA summer 2024 |
| Campbell CW4 | Heartnut bread by Doug Campbell of Ontario, Early pollinator, Compact tree with a good yield of medium size nuts, late pollinator. |  | TBA summer 2024 |
| England's Best | Large Size, Large Kernel, Wide Cavity, not convoluted Great taste. Heavy Crop, thin shell | TBA summer 2024 | |
| Fodermaier | This is an older heartnut selection from Dover Plains NY. It is rated high for cracking quality and production. It produces a large nut which drop out in halves and it ripens mid October. Protandrous , early pollinator. |  | TBA summer 2024 |
| Grimo Manchurican | US Heartnut that produces a good crop of medium sized easily cracked nuts, partly self-fertile | TBA summer 2024 | |
| Imschu | Reliable heavy cropping Canadian Heartnut that has medium sized nuts that crack out whole. Partly self-fertile and late pollinator. |  | TBA summer 2024 |
| Jewel Box | This cultivar of Heartnut was developed in Kentucky. It has a very large nut, and is a good producer; steady cropping every year. | TBA summer 2024 | |
| Schubert | Canadian Heartnut that produces medium nuts, partly self-fertile, late flowering and vigorous tree, parent of Imschu. |  | TBA summer 2024 |
| Stealth | A large elongated nut and a moderate producer. The nut meat drops freely out of the shell whole. It is an early pollinizer. Nuts ripen 2 weeks after 'Imshu'. |  | TBA summer 2024 |