Cortland Apple
Pollination & Compatibility Guide
Cortland apple pollination requirements, bloom group 3 overlap, and partner selection. Pomological guide covering non-browning flesh and cold hardiness.
Cortland is Self-Sterile (Needs 1 Partner)
Cortland needs at least one compatible pollinizer from bloom group 2–4 to set a reliable crop.
- Chromosome Ploidy
- Diploid (2n)
- Required Companions
- 1 Diploid Partner
- Bloom Group
- Group 3 (Mid-Spring)
- Harvest Timing
- Mid (-20d from Golden Delicious)
Flowering Period & Overlap Window
Apple flowering periods are classified into numbered bloom groups (1 through 6). A variety reliably cross-pollinates with cultivars in its own group or adjacent groups (±1 group).
Any compatible diploid apple flowering within Group 2 to 4 provides matching blossom overlap.
Compatible Pollination Partners (87)
| Cultivar | Bloom Group | Overlap Type | Harvest | Primary Uses | Interactive Test |
|---|---|---|---|---|---|
Fiesta (Red Pippin) | Group 3 | Full Overlap | Mid Concurrent (±0d) | Fresh Eating | Test Cross |
| Group 3 | Full Overlap | Early Concurrent (±0d) | Fresh Eating | Test Cross | |
Mother | Group 3 | Full Overlap | Mid Concurrent (±0d) | Fresh Eating | Test Cross |
Opalescent | Group 3 | Full Overlap | Mid Concurrent (±0d) | Fresh Eating | Test Cross |
Spartan | Group 3 | Full Overlap | Mid Concurrent (±0d) | All-Purpose | Test Cross |
| Group 3 | Full Overlap | Mid ±5d delta | All-Purpose | Test Cross | |
| Group 3 | Full Overlap | Mid ±5d delta | All-Purpose | Test Cross | |
| Group 3 | Full Overlap | Mid ±5d delta | All-Purpose | Test Cross | |
| Group 3 | Full Overlap | Mid ±5d delta | Fresh Eating | Test Cross | |
| Group 3 | Full Overlap | Mid ±5d delta | All-Purpose | Test Cross | |
Nova Easygro | Group 3 | Full Overlap | Mid ±5d delta | All-Purpose | Test Cross |
Connell Red | Group 3 | Full Overlap | Late ±10d delta | All-Purpose | Test Cross |
| Group 3 | Full Overlap | Mid ±10d delta | All-Purpose | Test Cross | |
Crimson Gold | Group 3 | Full Overlap | Late ±10d delta | All-Purpose | Test Cross |
| Group 3 | Full Overlap | Mid ±10d delta | Cider, Cooking | Test Cross |
Incompatible Varieties & Exclusions (19)
These varieties overlap in flowering time with Cortland but cannot fertilise it due to sterile pollen (triploids) or shared genetic incompatibility alleles.
Arkansas Black produces no viable pollen, so it cannot serve as a pollinizer.
Ashmead's Kernel produces no viable pollen, so it cannot serve as a pollinizer.
Baldwin produces no viable pollen, so it cannot serve as a pollinizer.
Belle de Boskoop produces no viable pollen, so it cannot serve as a pollinizer.
Blenheim Orange produces no viable pollen, so it cannot serve as a pollinizer.
Bramley's Seedling produces no viable pollen, so it cannot serve as a pollinizer.
Fall Pippin produces no viable pollen, so it cannot serve as a pollinizer.
Gravenstein produces no viable pollen, so it cannot serve as a pollinizer.
Jonagold produces no viable pollen, so it cannot serve as a pollinizer.
Karmijn de Sonnaville produces no viable pollen, so it cannot serve as a pollinizer.
A direct parent (Ben Davis × McIntosh) — roughly half the pollen is non-functional, so it is not a reliable partner.
Mutsu (Crispin) produces no viable pollen, so it cannot serve as a pollinizer.
Orleans Reinette produces no viable pollen, so it cannot serve as a pollinizer.
Ribston Pippin produces no viable pollen, so it cannot serve as a pollinizer.
Roxbury Russet produces no viable pollen, so it cannot serve as a pollinizer.
Spigold produces no viable pollen, so it cannot serve as a pollinizer.
Stayman Winesap produces no viable pollen, so it cannot serve as a pollinizer.
Tompkins King produces no viable pollen, so it cannot serve as a pollinizer.
Zabergau Reinette produces no viable pollen, so it cannot serve as a pollinizer.
Grower Commentary: Cortland Pollination, Hang Time & Cold Hardiness
Cortland is a diploid, self-sterile cultivar developed at the New York State Agricultural Experiment Station from a cross of Ben Davis × McIntosh (released 1915). Flowering in bloom group 3 (mid-season), it produces abundant viable pollen and cross-pollinates readily with companion diploids such as Gala, Honeycrisp, Empire, and Discovery.
Parentage exclusions: Descending directly from McIntosh, Cortland shares self-incompatibility alleles with McIntosh and should not be planted with McIntosh as its exclusive pollination source.
Excellent hang time and non-browning flesh: Unlike its parent McIntosh, which drops readily before harvest, Cortland fruit hangs securely on the branch well past initial maturity without substantial pre-harvest drop. The bright white flesh is exceptionally slow to oxidize and brown when sliced, making it highly prized for commercial salads, baking, and fresh cider blending.
Cold tolerance and vigor: Displays outstanding winter hardiness down to USDA Zone 4. Tree architecture is moderately vigorous with spreading branches and heavy lateral spur development, benefiting from regular branch thinning to maintain sunlight on interior fruiting wood.
Key Orchard Considerations for Cortland
Fruit hangs securely on the tree without the severe pre-harvest drop issues characteristic of parent McIntosh.
Do not rely on McIntosh or close sibling crosses as sole cross-pollinizers due to shared maternal alleles.
Robust winter survival in northern apple-growing regions where tender cultivars suffer winterkill.
Take Cortland from Planning to Planting
Use Kropigo's free browser tools to model your block density, tree counts, and pollinizer rows, then maintain permanent orchard records row by row.
Pollination Checker
Check Cortland against supported cultivars with compatible flowering and pollination data.
Commercial Block Planner
Calculate high-density tree spacing, row geometry, and establishment costs.
Block Record Keeping
Track pruning, chemical thinning, and harvest tallies block by block from the orchard.