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Can You Repeat Your Best Harvest?

Enter your last 4-6 harvest yields. See how much your production actually swings, what that inconsistency costs you, and what locking in your best run would mean in real dollars.

📏 How Do You Measure Yield?
🌱 Your Last Harvests
Yield (lb/light) Strain (optional)
📈 Dollar Impact Context
Number of Lights ?This scales the yield gap into total pounds so we can show you the dollar impact across your whole operation. Per room
Harvests per Year ?How many times per year do you harvest the same room? Used to annualize your consistency gap. Typical range is 4-6 for indoor. Same room, per year
Flower Rooms ?Total flower rooms in your facility. Scales the dollar impact. If you only want to see one room, leave at 1. Total active rooms
Wholesale Price ?Your average net price per pound. Used to translate the consistency gap into dollars. Doesn't affect your consistency score. $/lb
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All calculations happen in your browser. Nothing is sent to our servers. Coefficient of variation is a standard statistical measure of relative dispersion.
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Enter at least 3 harvests

Your consistency analysis, yield chart, and dollar impact will appear here as you type.

Frequently Asked Questions

What exactly is "coefficient of variation"?
Coefficient of variation (CV) is a standard statistical measure that shows how much your data points vary relative to the average. It's calculated as (standard deviation / mean) × 100. A CV of 10% means your yields typically land within 10% of your average. A CV of 30% means there's a wide swing. It's the same metric used in manufacturing quality control, agricultural research, and any field where consistency matters.
Why should I compare the same strain separately?
Different strains produce different yields naturally. If you mix Wedding Cake and Runtz in the same analysis, some of your "variation" is just genetics, not process inconsistency. Entering strain names lets the tool show you per-strain consistency, which isolates your actual process variation from genetic differences. The overall number is still useful for understanding your facility's production predictability, but per-strain breakdowns give you cleaner signal.
Why does the dollar impact say "almost pure margin"?
Most of your costs are fixed: rent, labor, electricity, equipment payments. These stay roughly the same whether you pull 80 lbs or 100 lbs from a room. The marginal cost of producing more pounds (a bit more nutrients, a bit more processing time) is a fraction of the wholesale price. So when you close the gap between your average and your best, most of that extra revenue drops straight to your bottom line. That's why consistency is a profitability multiplier, not just a yield metric.
How many harvests should I enter?
Four is the minimum for a meaningful consistency calculation. Six to eight gives you a better picture because it captures more of your natural variation. If you've had an outlier harvest (fire, equipment failure, pest event), you can include it or skip it. The tool treats all entries equally.
Does this tool track my data?
No. All calculations happen in your browser. Nothing is sent to our servers. Your inputs are saved in your browser's local storage so they persist when you return, but that data never leaves your device.

Why Yield Consistency Matters More Than Peak Performance

Every commercial grower remembers their best run. The one where everything clicked, the canopy was perfect, and the dry weight exceeded expectations. But the question that determines whether an operation survives long-term isn't "how high can you go?" It's "how often can you repeat it?"

Yield consistency, measured by coefficient of variation (CV), captures something that average yield alone misses: how much your results swing from harvest to harvest. And that swing has a direct dollar cost.

The Cost of Inconsistency

When yields vary, so does revenue. But costs don't. Rent, labor, electricity, and loan payments stay the same whether you harvest 25 pounds or 35 pounds from a room. That means every below-average harvest directly increases your effective cost per pound, and the gap between your best run and your worst run represents real money left on the table.

Coefficient of Variation Rating What It Means
Under 5% Locked In Highly repeatable. Process is dialed. Revenue is predictable.
5-10% Solid Good consistency. Minor variation is normal across seasons and strains.
10-20% Room to Tighten Notable swings. Something is changing between runs that shouldn't be.
Above 20% High Variation Major inconsistency. Likely losing thousands per year to unpredictable output.

What Drives Yield Variation

Yield variation in commercial cannabis cultivation comes from a predictable set of sources. Research published in HortScience and the Journal of Cannabis Research identifies the primary drivers:

Environmental inconsistency. VPD swings, temperature fluctuations during lights-off, and humidity spikes in late flower all impact final weight. The data typically shows 3-8% yield impact from environmental drift that goes unnoticed on a daily basis but compounds over a 9-week flower cycle.

Genetic variation within the same strain. Unless you're running clones from the same mother, phenotypic variation alone can account for 5-15% yield difference between plants. This shows up in canopy uniformity issues that are visible in overhead photos well before harvest.

Nutrition drift. EC and pH that drift 0.2-0.3 from target during mid-flower can reduce final weight by 5-10% without any visible deficiency symptoms until late in the cycle. Runoff data tells the story, but only if someone is watching it consistently.

IPM events. Even a mild pest pressure event (russet mites, thrips, powdery mildew) that doesn't cause visible damage can reduce trichome production and final dry weight by 5-15%. Operations that don't track pest pressure alongside yield data miss this connection entirely.

From Variation to Consistency

The path from high variation to tight consistency starts with tracking. You can't fix what you don't measure, and you can't identify patterns across runs without structured data. The most consistent operations track batch-level data including environment, nutrition, plant health observations, and final yield for every run.

The real power comes from comparison. When you can put your best run next to your worst run and see exactly what was different (environment, feed schedule, canopy photos, timing), the patterns become obvious. The consistency gap closes when those patterns stop repeating.

Use the Grow Efficiency Scorecard to benchmark where you stand, or learn more about how data-driven yield optimization works in practice.

These tools exist because I needed them. I'm Eric, commercial grower and software engineer in Michigan. I built Growgoyle to run my own facility and these calculators are just a piece of it. If you're running a grow and want to talk shop, text me.

Text me: 616-221-9856  ·  info@growgoyle.ai

- Eric