Illustrative feeding program · agronomic review required
Example block: 30.0 1,000 lb fruit/ac. Mature commercial planting with zero assumed soil, water or other nutrient credits.
125.0 lb N/ac
Seasonal fertilizer nitrogen61.5 lb K2O/ac
Seasonal potassium budget153.2 lb Ca/ac
Calcium supplied by CALTRATE
How to read this schedule: bold amounts are total product pounds per acre for the entire stage. Divide them across the separate applications shown. Dates are approximate; use actual crop stage. All rates shown are for root-zone fertigation, not foliar spraying.
| Growth stage / timing | NABTA CALTRATE
15.5-0-0 + Ca19 | NABTA SOP
0-0-52 |
|---|
| Winter slow growthBefore spring flush | No routine application0 lb/ac in this example | No routine application0 lb/ac in this example |
| Spring flushFeb–Mar; local phenology | 268.8 lb/acStage total: 9 separate applications × 29.9 lb/ac each | 23.7 lb/acStage total: 2 separate applications × 11.8 lb/ac each |
| Bloom / fruit setApr–May | 268.8 lb/acStage total: 9 separate applications × 29.9 lb/ac each | 35.5 lb/acStage total: 2 separate applications × 17.7 lb/ac each |
| Fruit expansionJun–Jul | 134.4 lb/acStage total: 5 separate applications × 26.9 lb/ac each | 35.5 lb/acStage total: 2 separate applications × 17.7 lb/ac each |
| Late fruit expansionAug–early Sep | 134.4 lb/acStage total: 5 separate applications × 26.9 lb/ac each | 23.7 lb/acStage total: 2 separate applications × 11.8 lb/ac each |
| Maturation / harvestCultivar and district dependent | No routine application0 lb/ac in this example | No routine application0 lb/ac in this example |
| Winter restNo routine winter feeding | No routine application0 lb/ac in this example | No routine application0 lb/ac in this example |
Season total CALTRATE: 806.5 lb/acSeason total SOP: 118.3 lb/ac
Assumptions & adjustments
- 125 lb N/ac is an illustrative midpoint of the 100–150 lb/ac navel-orange trial range at about 100 trees/ac.
- Two-thirds of N is allocated from spring flush through fruit set. Finish by early fall; K split is proposed.
- K replacement uses 2.05 lb K2O/1,000 lb fruit. Do not transfer this example unchanged to lemons or mandarins.
- The navel-orange example has not been extended to mandarins, lemons or grapefruit. Request a crop-specific plan for those crops.
- No routine phosphorus or micronutrient dose is included. These examples assume adequate phosphorus; other nutrients require diagnostic evidence.
- Application counts are arithmetic subdivisions using 30 lb CALTRATE/ac and 20 lb SOP/ac as maximum example event sizes. Confirm current label directions, irrigation frequency, injection capacity, EC and calcium loading. Do not add irrigation solely to fit the schedule.
Product compatibility: apply CALTRATE separately from SOP, MKP, LIB and other phosphate or sulfate solutions, with appropriate flushing. Confirm the current California registration and label for SOP before purchase or use; its current status has not been verified for this example.
Research basis: UC / CDFA crop nutrition reference. Product analyses: CALTRATE label reference · SOP label reference. These references do not imply UC endorsement of NABTA products.
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