Heyer #12 Apple

Heyer #12 Apple (Malus ‘Heyer #12’) Care Guide

Overview:
Heyer #12 is a cold-hardy apple variety developed in Saskatchewan around 1940 by A. Heyer. It is valued in prairie and northern climates for its toughness under harsh conditions. 
The fruit is medium-sized, greenish-yellow, with a coarse white flesh. It is primarily considered a cooking apple, as it tends to be quite tart and oxidizes quickly. 
It is also noted for its drought resistance and moderate growth rate, and it requires a pollinator to set fruit. 

1. Planting & Growing Conditions

• Hardiness Zone: Very hardy; reports suggest success even beyond zone 2. 

• Mature Size & Habit:
   • Produces a moderately vigorous, open spreading tree with wide-angled branches. 
   • Trees bear fruit as early as 3 years old under good conditions. 

• Light Requirements: Full sun (at least 6+ hours) is ideal for fruit production and health.

• Soil:
   • Prefers well-drained, moderately fertile soils. 
   • Adaptable to somewhat dry or marginal soils given its drought tolerance. 

• Spacing: Leave ample space to accommodate the tree’s spreading habit and ensure good air circulation.

2. Fruit & Harvesting

• Ripening Time: Early to mid August (early season). 

• Fruit Characteristics:
   • Diameter: ~5–6 cm (approx. 2 to 2½ inches) 
   • Skin: Greenish-yellow to straw-colored when fully mature. 
   • Flesh: White, medium-coarse texture, tart to mildly acidic. 

• Uses: Best suited for cooking, baking, sauces, and preserves. Not typically eaten fresh due to tartness and oxidation. 

• Storage: Very limited — tends to store only 1-2 weeks under cold conditions. 

• Harvesting Note: Because the fruit tends to drop as it ripens, it should be picked just before full maturity for best retention. 

3. Pollination & Fruit Set

• Self-sterile: Heyer #12 requires a different apple or crabapple variety that blooms around the same time for cross-pollination. 

• The pollinator should overlap bloom timing and be within proximity to facilitate pollination.

4. Watering & Establishment

• During the first 2–3 years, provide regular watering during dry periods to help the root system establish itself.

• After established, Heyer #12 demonstrates drought resilience, but supplemental watering in drought helps maintain productivity and health. 

• Use mulch to conserve moisture and moderate soil temperature, while keeping it away from the trunk.

5. Fertilizing

• Apply a balanced, slow-release fertilizer in early spring to support vegetative growth and fruiting.

• Avoid over-fertilization—especially high nitrogen—that may reduce fruit quality or increase disease susceptibility.

6. Pruning & Maintenance

• Best Time: Late winter to early spring, while the tree is dormant.

• How to Prune:
   • Remove dead, diseased, or crossing branches.
   • Thin interior growth to improve light penetration and airflow.
   • Avoid heavy pruning in late summer, which can stress the tree or delay fruiting.

7. Pest & Disease Considerations

• Heyer #12 is reported to be very resistant to fire blight, one of the more serious apple diseases in many climates. 

• However, as with all apple trees, be wary of common issues such as apple scab, codling moth, aphids, leaf spots, rusts, and others.

• Practices to reduce risk: good sanitation (clean fallen leaves/fruit), good airflow, proper pruning, and monitoring for early signs.

8. Winter & Cold Protection

• Extremely cold-hardy, often successful in the coldest apple-growing zones. Reports indicate hardiness to zone 1 by some sources. 

• In exposed or young trees, consider trunk guards or mulching to protect against winter sunscald and frost damage.

9. Landscape Uses

Excellent choice for northern orchards and cold-climate apple growers
Can be used as a small to medium yard fruit tree
Good as a production tree for cooking apples in home or small-scale orchard settings
Works well in mixed fruit plantings where diversity of harvest times is desired