HEARTNUT WALNUTS
Other Common Names Include:
Japanese Walnut
Latin Name: Juglansailantifolia var. cordiformis
Plant Family: Juglandaceae
Close Relatives: Japanese walnut,Butternut, Black walnut, English walnut
Uses and Markets: Culinary (e.g. Valentine’s chocolates, candies and cakes); Industrial (e.g. shells can be used for mulches, crafts and air blast materials); Ornamental
Production Life Cycle in Ontario
Perennial
Hardiness Zone
6
Special Notes
The trees are hardy to Zone 5 but production in Zone 5 is limited by spring frosts that kill the developing flower buds. The heartnut is a sport (natural mutation) of the Japanese walnut with heart shaped nuts. Pollination is improved by planting two or more varieties.
Propagation method
Transplant of potted or bare root trees propagated from seed or grafting onto butternut or black walnut root stock.
Greenhouse Seeding/Propagation Dates
Spring
Field Seeding Date:
N/A
Field Transplanting Dates
April to May
In-row spacing
6 - 8m
Between row spacing
6 - 8m
Optimal Soil temperature at planting
>10°C
Fertility
No current Ontario fertility recommendations exist. Research and recommendations from outside Ontario do not necessarily apply to Ontario growing conditions. No research has been conducted into the nitrogen requirements of heartnut Click here for phosphorus and potassium application guidelines and for more information on specialty crop fertility.
Soil type
Well-drained soils, moist sandy loam to clay loam soils.
Soil pH
6.0-7.0
Special requirements for growth habit
None
Optimal Temperature Range
12-30°C
Temperature sensitivity
Freeze tolerant (trees); frost sensitive (flowers).
Irrigation requirements
Irrigation beneficial under normal Ontario conditions.
Days to harvest
Nuts produced as early as 1 to 3 years for grafted trees, but commercial production begins in 6-8 years.Takes 140 days from flowering to nut maturity each year.
Specialized equipment
Dehusking drum, pruning equipment/platforms, air-blast sprayer, nut cleaning, dehydrators, cracking, sorting.
Harvest
Early to late September.
Harvest Scheduling
Single harvest
Hand harvest or machine harvest
Machine harvest for large plantings; hand harvest for smaller plantings.
Quality parameters/grades
No established grades. Quality is determined by the market. Due to variability in seeded trees, cracking quality is variable. Marketable nuts must be able to crack easily.
Additional Harvest Notes
Nuts are normally allowed to fall to the ground and are picked up with hand-held or larger equipment.
Post harvest
Special handling/curing
Shell nuts and dehydrate kernels before long-term cold.
Storage Conditions
Relative humidity (RH): Low humidity will prolong shelf-life.
Temperature: <0˚C.
Air Exchange: N/A
Duration: Up to 2 years if frozen
Specific pests observed on this crop in Ontario (observations based on limited experience with this crop)
Insects and Invertebrates: Butternut curculio, walnut husk fly/maggot, codling moth, leafrollers, leafhoppers, aphids, scale, Japanese beetle, pale green weevil
Diseases: Walnut bunch disease (witch’s broom), crown gall, butternut canker (stressed trees), walnut blight (Xanthomonusspp.)
Other: Squirrels, birds (especially grackles), deer
Other Potential Pests: The following pests have not been observed on this crop in Ontario. However, they are either significant concerns for closely related plants in Ontario, or are reported on this crop in other production areas. This is not a comprehensive list of all potential pests. Not all of these pests will necessarily survive Ontario’s climate, but could potentially survive in a protected environment (e.g. greenhouse, storage facility).
Insects and Invertebrates: Mites, brown marmoratedstink bug
Diseases: Walnut weevil (Conotrachclusjuglandis)
Other:
*Indicates pests commonly mentioned as causing significant damage or economic loss to this crop in other regions.
Comments
To date the following pests have been the most significant in Ontario: butternut curculio, husk maggot. For more information on Crop Groups, refer to the Pest section. Always refer to product labels, and follow all directions specified on the label, before applying any pest control product. For more information, consult an OMAFRA specialist.
A recommended ground cover for Heartnut trees is Dwarf perennial rye.
Cultivar research trials – The University of Guelph, at the Simcoe Research Station and the Vineland Research and Innovation Centre, is testing several dozen cultivars of hazelnuts to determine suitability for fresh market and confectionary markets, tolerance or resistance to Eastern Filbert Blight disease, which has prevented commercialization in Ontario previously, cold tolerance during winter, frost tolerance in spring, cross-pollination to maximize cropping, pest management program development.
Minor use registration – Agriculture and Agri-Food Canada at Harrow is conducting field trials to achieve minor use registration of herbicides for use on Hazelnuts in Canada. Field trials for minor use registration of insecticides, fungicides and biological pest control will be included in the future.
Hazelnut pest management – OMAFRA Crop Specialists. Surveys and timely site inspections at private hazelnut farms and hazelnut research sites are conducted to develop an effective pest management program for Ontario.
- Leuty, T, D. Galic, P. Bailey, A. Dale, E. Currie and M. Filotas. 2012. Hazelnuts in Ontario – Growing, Harvesting and Food Safety. Ontario Ministry of Agriculture and Food and Ministry of Rural Affairs Factsheet #12-011, Agdex 240.
- Dale, A, D. Galic, T. Leuty, M. Filotas and E. Currie. 2012. Hazelnuts in Ontario - Biology and Potential Varieties. Ontario Ministry of Agriculture and Food and Ministry of Rural Affairs Factsheet #12-007, Agdex 240.
- M. Filotas, A. Dale, D. Galic, T. Leuty, E. Currie 2012. Hazelnuts in Ontario – Pests. Ontario Ministry of Agriculture and Food and Ministry of Rural Affairs Factsheet #12-009, Agdex 240.
