How to Use This Calendar
Biological inputs are timing-sensitive in a way that synthetic fertilizers are not. Enzyme and microbial products work through living soil systems that respond to temperature, moisture, and crop growth stage. Applying at the right window — when soil is warm, moist, and biologically active — maximizes the return on every dollar spent on biological inputs.
This calendar organizes application timing by major US crop region and key crop systems. Use it alongside your soil test results and local extension guidance.
Corn Belt: Iowa, Illinois, Indiana, Ohio, Minnesota, Wisconsin
Corn Program
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy soils) | April–May | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast pre-plant |
| At-plant | May | ZyDrive | 1 gal/acre | In-furrow with starter fertilizer |
| At-plant (nematode/disease pressure) | May | ProMax | 1 gal/acre | In-furrow with starter fertilizer |
| Critical growth stage foliar | V-to-R transition (June–July) | Enhance | 2 qt/acre | Foliar at V-to-R |
| Spoon feeding (optional) | 20–30 days post-emergence | Enhance | 1 qt/acre/week | Weekly foliar |
Soybean Program
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy soils) | May | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast pre-plant |
| At-plant | May | ZyDrive | 1 gal/acre | In-furrow with starter |
| V-to-R transition | R1 (July) | Enhance | 2 qt/acre | Foliar at bloom onset |
Southern Plains: Kansas, Oklahoma, Texas (Winter Wheat & Dryland)
Winter Wheat Program
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy soils) | September–October | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast before drilling |
| At drilling | September–October | ZyDrive | 1 gal/acre | In-furrow with starter |
| Jointing foliar | March–April | Enhance | 2 qt/acre | Foliar at Feekes 6 (V-to-R) |
Dryland Sorghum & Milo
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy soils) | May–June | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | May–June | ZyDrive | 1 gal/acre | In-furrow with starter |
| Critical growth stage | 6–8 leaf stage | Enhance | 2 qt/acre | Foliar at V-to-R |
Northern Plains: North Dakota, South Dakota, Montana, Minnesota
Spring Wheat & Durum
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy/wet soils) | April–May | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | May | ZyDrive | 1 gal/acre | In-furrow with starter |
| Tillering foliar | Feekes 4–5 (June) | Enhance | 2 qt/acre | Foliar at V-to-R |
Canola & Sunflowers
| Timing | Product | Rate | Method |
|---|
| Pre-plant (heavy/wet soils) | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | ZyDrive | 1 gal/acre | In-furrow with starter |
| Rosette/Early bolt | Enhance | 2 qt/acre | Foliar at V-to-R transition |
Southeast & Mid-Atlantic: Georgia, Carolina, Alabama, Virginia
Cotton
| Timing | Month | Product | Rate | Method |
|---|
| Pre-plant (heavy/wet soils) | April | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | April–May | ZyDrive | 1 gal/acre | In-furrow with starter |
| Pinhead square / First bloom | June–July | Enhance | 2 qt/acre | Foliar at V-to-R transition |
Peanuts
| Timing | Product | Rate | Method |
|---|
| Pre-plant (heavy soils) | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | ZyDrive | 1 gal/acre | In-furrow with starter |
| Early peg / Pegging | Enhance | 2 qt/acre | Foliar at V-to-R transition |
Western States: California, Idaho, Washington, Oregon
Irrigated Vegetables & Specialty Crops
| Timing | Product | Rate | Method |
|---|
| Pre-plant (heavy/wet soils) | PervaideMax | 1 gal/acre (6:1 water mix) | Broadcast |
| At-plant | ZyDrive | 1 gal/acre | In-furrow with starter |
| Critical growth stage | Enhance | 2 qt/acre | Foliar at V-to-R transition |
| Spoon feeding | Enhance | 1 qt/acre/week | Weekly foliar from 20–30 days post-emergence |
Key Principles for All Regions
- Soil temperature matters: Biological activity is minimal below 50°F. Pre-plant applications in cold soils should target warming conditions — wait until 5-inch soil temp is consistently above 50°F for maximum enzyme activity.
- Moisture is essential: Apply when soil is moist or rain is expected within 72 hours. Dry application followed by drought delays product performance.
- Year one vs. year three: First-year results from biological programs are real but modest. The soil system responds cumulatively — year-three fields in a consistent biological program routinely outperform year-one fields by 30–50% in measured outcomes.
- Don't skip pre-plant: Pre-plant application consistently delivers the highest single-application return across crops and regions. If you have budget for one application, this is it.
