Knight's Early Black Sweet Cherry
Pollination & Compatibility Guide
Knight's Early Black cherry pollination: S-genotype (S1S2, Group I), early bloom overlap, compatible partners, and heritage orchard management.
Knight's Early Black is Self-Incompatible (Needs 1 Partner)
Group I — mutually sterile with Black Tartarian, Early Rivers, Bedford Prolific and Summit. Very early bloom, so partner choice is constrained more by bloom overlap than by genotype. Knight's Early Black needs at least one compatible pollinizer from bloom group 1–3 to set a reliable crop.
- S-Genotype / Genetics
- S1S2 (Group I)
- Required Companions
- 1 Compatible Partner
- Bloom Group
- Group 2 (Early-Mid Spring)
- Harvest Timing
- Early-Mid Season
Flowering Period & Overlap Window
Sweet and sour cherry flowering periods are classified into numbered bloom groups (1 through 5). Cross-pollination requires overlapping bloom timing between genetically compatible cultivars.
Any compatible cherry cultivar flowering within Group 1 to 3 provides matching blossom overlap.
Compatible Pollination Partners (12)
| Cultivar | Bloom Group | Overlap Type | Harvest | Primary Uses | Interactive Test |
|---|---|---|---|---|---|
| Black PearlGuide | Group 2 | Full Overlap | Early | Fresh Eating | Test Cross |
| ChelanGuide | Group 2 | Full Overlap | Early | Fresh Eating | Test Cross |
| BingGuide | Group 3 | Full Overlap | Mid-Late | Fresh Eating, Canning | Test Cross |
| Emperor FrancisGuide | Group 3 | Full Overlap | Mid | Canning, Fresh Eating | Test Cross |
| KristinGuide | Group 3 | Full Overlap | Mid | Fresh Eating | Test Cross |
| RainierGuide | Group 3 | Adjacent Overlap | Mid | Fresh Eating, Dessert | Test Cross |
| SchmidtGuide | Group 3 | Adjacent Overlap | Mid | Fresh Eating | Test Cross |
| SelahGuide | Group 3 | Full Overlap | Mid | Fresh Eating | Test Cross |
| StellaGuide | Group 3 | Full Overlap | Mid | Fresh Eating, All-Purpose | Test Cross |
| SunburstGuide | Group 3 | Full Overlap | Mid | Fresh Eating | Test Cross |
| UlsterGuide | Group 3 | Full Overlap | Mid | Fresh Eating | Test Cross |
| VanGuide | Group 3 | Adjacent Overlap | Mid | Fresh Eating, Canning | Test Cross |
Incompatible Varieties & Exclusions (2)
These cherry varieties overlap in flowering time with Knight's Early Black but cannot fertilise it due to shared S-allele genetic incompatibility groups.
Black Tartarian shares both S-alleles with Knight's Early Black — they are mutually sterile, whatever their bloom overlap suggests.
Merton Glory's S-genotype is not recorded. For this crop compatibility is computed from S-alleles, so it cannot be offered as a partner without one.
Knight's Early Black Heritage Pollination & Culture
Knight's Early Black is a historic English sweet cherry bred around 1810 by celebrated pomologist Thomas Andrew Knight (Bigarreau × May Duke). Prized for centuries for its early ripening, dark glossy fruit, and rich, sweet, tender flesh, it holds a distinguished place in heritage orchards, connoisseur collections, and historic walled fruit gardens across Britain and Europe.
Classified in Incompatibility Group I (S1S2), Knight's Early Black is gametophytically self-sterile and cannot pollinate other Group I cultivars like Black Tartarian and Early Rivers. It is cross-compatible with Group III (Bing, S3S4), Group XVI (Chelan, S3S9), and self-fertile universal donors like Stella (S3S4′), Skeena (S1S4′), and Lapins (S1S4′).
Knight's Early Black flowers very early in Bloom Group 1. Choosing companion pollinizers with matching early bloom dates (Bloom Groups 1 and 2) is essential to achieve robust flower overlap during early spring weather, ensuring reliable blossom fertilisation and dependable heritage dessert fruit yields year after year.
Key Orchard Considerations for Knight's Early Black
Very early flowering makes flower buds highly susceptible to late winter and early spring frosts. Select protected, north-wind-sheltered planting sites with good air drainage.
Produces soft, succulent fruit with deeply coloured juice, exceptional for immediate fresh eating, traditional jams, and classic stone fruit desserts.
Displays moderate vigor with open, spreading branches. Prune gently in summer to prevent silver leaf disease and preserve productive fruiting spurs on older wood.
Take Knight's Early Black from Planning to Planting
Use Kropigo's free browser tools to model your block density, tree counts, and pollinizer rows, then maintain permanent field records row by row.
Pollination Checker
Test Knight's Early Black against custom candidate lists across all 439 varieties.
Commercial Block Planner
Calculate high-density tree spacing, row geometry, and establishment costs.
Field Record Keeping
Track pruning, chemical thinning, and harvest tallies block by block from the field.