Seeding Rate Calculator Canola

Canola Seeding Rate Calculator

Calculation Results

Seeding Rate: —

Seeds Per Acre: —

Total Seed Required: —

function calculateCanolaRate() { var target = parseFloat(document.getElementById('targetPopulation').value); var tsw = parseFloat(document.getElementById('tsw').value); var survival = parseFloat(document.getElementById('survival').value); var acres = parseFloat(document.getElementById('acres').value); if (isNaN(target) || isNaN(tsw) || isNaN(survival) || survival <= 0 || target <= 0 || tsw <= 0) { alert("Please enter valid positive numbers for all fields."); return; } // Formula: Seeding rate (lb/ac) = (Target plants/ft2 x TSW in grams) / (Survival % x 10) // Example: (7 x 5) / (60 / 100 * 10) = 35 / 6 = 5.83 var rate = (target * tsw) / (survival / 10); // Seeds per acre calculation var seedsPerAcre = (target / (survival / 100)) * 43560; // Total seed for the specified acreage var totalSeed = rate * acres; document.getElementById('seedingRateResult').innerText = rate.toFixed(2) + " lbs/acre"; document.getElementById('seedsPerAcre').innerText = Math.round(seedsPerAcre).toLocaleString() + " seeds"; document.getElementById('totalSeedResult').innerText = totalSeed.toFixed(0).toLocaleString() + " lbs"; document.getElementById('canola-results').style.display = 'block'; }

Optimizing your canola seeding rate is one of the most critical decisions in the spring. Unlike many other crops, canola has a high capacity for compensation, but achieving a uniform plant stand of 5 to 8 plants per square foot is essential for maximizing yield potential, managing weed competition, and ensuring even maturity for harvest.

The Canola Seeding Rate Formula

Calculating the correct amount of seed to put in the drill requires more than just picking a standard number. It is based on four primary variables:

• Target Plant Population: The desired number of plants that emerge. Research from the Canola Council suggests 5-8 plants per square foot is the "sweet spot" for yield and competition.
• Thousand Seed Weight (TSW): This is the weight in grams of 1,000 individual seeds. Because seed sizes vary significantly between batches and varieties, you must check the seed tag. A TSW can range from 3.5g to over 6.0g.
• Seedling Survival: Not every seed you plant will grow. Factors like soil moisture, seeding depth, temperature, and insect pressure (flea beetles) impact survival. On average, canola survival is roughly 60%, but it can range from 40% to 90% depending on conditions.

Why TSW Matters

If you keep your seeding rate at a constant 5 lbs/acre regardless of seed size, your plant population will fluctuate wildly. For example, if you have a TSW of 4.0g, 5 lbs/acre provides a high density of seeds. However, if the TSW is 6.0g, that same 5 lbs/acre results in 33% fewer seeds per acre, potentially leaving your field thin and vulnerable to weeds.

Example Calculation

Suppose you want to achieve a target of 7 plants/ft². You check your seed bag and see the TSW is 5.0 grams. You estimate your survival at 60% because the soil is slightly cold.

Calculation: (7 plants/ft² × 5.0 TSW) ÷ (60% Survival ÷ 10) = 5.83 lbs/acre.

Management Tips for Better Stand Establishment

1. Seed Shallow: Aim for 0.5 to 1 inch depth. Seeding deeper than 1 inch significantly reduces seedling survival.
2. Monitor Speed: Excessive seeding speed can lead to uneven depth and poor seed-to-soil contact.
3. Test Soil Temp: Canola can germinate at 2-3°C, but 10°C is ideal for rapid, uniform emergence.
4. Adjust for Conditions: If you are seeding into heavy trash or extremely dry soil, decrease your expected survival percentage in the calculator to increase your seeding rate.