Fresh herbs from your own growing can significantly lower your food cost, but only if you calculate the real costs correctly. Many restaurant owners forget to include the initial investment and maintenance, which makes them think their herbs are 'free'. In this article, you'll learn step-by-step how to calculate the real cost price per portion of homegrown herbs.
Why homegrown herbs aren't free
A pot of basil at the supermarket costs €2.50 for 20 grams. That's €125 per kilo - pretty expensive. It makes sense that you think: 'I'll just grow it myself.' But watch out that you don't forget to count all the costs.
⚠️ Heads up:
Many entrepreneurs only count seeds and potting soil, but forget labor costs, water, electricity, and space. Then it looks cheaper than it actually is.
All costs of herb growing
For a fair cost price calculation, you add up all costs:
- Initial investment: Pots, potting soil, seeds, possibly grow lights
- Ongoing costs: Water, electricity (heating/lighting), new seeds
- Labor costs: Time for sowing, watering, harvesting, processing
- Space costs: The square meters you use for growing
- Loss: Plants that die, leaves that aren't usable
Calculate your yield realistically
A basil plant doesn't produce endlessly. Calculate a realistic yield per plant and per cycle.
💡 Example basil yield:
Per plant over 3 months:
- Usable leaves: 80-120 grams
- Loss (bad leaves): 20%
- Net yield: 65-95 grams per plant
Average: 80 grams per plant per cycle
Cost price calculation with example
Let's calculate what basil from your own growing actually costs:
💡 Example: 10 basil plants
Initial costs (one-time):
- 10 pots: €30
- Potting soil: €15
- Seeds (multiple seasons): €10
- Grow light: €80
Total initial investment: €135
Costs per cycle (3 months):
- Electricity for grow light: €25
- Water: €5
- Labor (5 min/day × 90 days × €15/hour): €112.50
- Space (1m² × €10/month × 3): €30
Total per cycle: €172.50
From total costs to cost price per gram
Now you calculate the cost price by dividing all costs by your yield:
💡 Cost price calculation:
10 plants × 80 grams = 800 grams per cycle
Initial costs depreciated over 8 cycles (2 years): €135 ÷ 8 = €16.88 per cycle
Total costs per cycle: €172.50 + €16.88 = €189.38
Cost price: €189.38 ÷ 800 grams = €0.24 per gram
That's €240 per kilo - almost twice as expensive as supermarket basil! The labor costs make the difference.
When homegrown is worth it
Growing your own can be worthwhile if:
- You use expensive herbs: Like fresh thyme, rosemary, tarragon (€300-500/kg)
- You already have space and facilities: Existing greenhouse or growing area
- Your team has spare time: To do maintenance during quiet periods
- You use large quantities: Economies of scale with more plants
💡 Example: Tarragon growing
Tarragon costs €450/kg from the wholesaler. With the same calculation:
Homegrown: €240/kg
Savings: €210/kg = 47% cheaper
Calculate cost price per portion
For your food cost calculation, you need the cost price per portion:
Cost price per portion = Amount used × Cost price per gram
💡 Example portion costs:
You use 2 grams of fresh basil per pasta:
2 grams × €0.24 = €0.48 per portion
Supermarket basil: 2 grams × €1.25 = €2.50 per portion
In this case, supermarket basil is actually cheaper, despite the high kilo price.
How do you calculate the cost price of homegrown herbs? (step by step)
Inventory all costs
Make a list of initial costs (pots, soil, seeds, equipment) and ongoing costs (water, electricity, labor, space). Don't forget any cost item - including your own time.
Measure your actual yield
Weigh how much usable herbs you harvest per plant during a full cycle. Subtract loss for leaves you can't use. This gives you the net yield per plant.
Calculate cost price per gram
Divide your total costs per cycle by your total yield in grams. Depreciate initial investments over multiple cycles (for example 2 years). This gives you the real cost price per gram.
Determine portion costs for your dishes
Multiply the cost price per gram by the amount you use per dish. This is the herb cost you include in your food cost calculation.
✨ Pro tip
Keep a log of your actual yield and costs throughout a whole season. Many entrepreneurs estimate too optimistically and think their herbs are cheaper than they actually are.
Calculate this yourself?
In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
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Frequently asked questions
Should I include labor costs if I take care of the herbs myself?
Yes, absolutely. Your time has value and costs you money. Calculate with your hourly rate or at least €15 per hour. Otherwise you'll get a distorted picture of the real costs.
How long can I depreciate my initial investment?
Calculate with 2 years for pots and equipment. That's about 8 growing cycles of 3 months each. Spread the purchase costs over this period for a fair cost price calculation.
Which herbs are most profitable to grow yourself?
Expensive herbs like tarragon, fresh thyme, rosemary, and sage are most worthwhile. These cost €300-500 per kilo from the wholesaler. Cheap herbs like parsley are often more expensive when grown yourself.
How do I factor in space costs?
Calculate what a square meter costs in your kitchen per month (rent + energy divided by total area). Multiply this by the space your growing takes up. Budget €8-12 per m² per month.
What if my plants die or grow poorly?
Always calculate with loss. Count the number of failed plants in your costs, but not in your yield. A loss percentage of 15-25% is normal for beginning growers.
📚 Sources consulted
- EU Verordening 852/2004 — Levensmiddelenhygiëne (2004) — Official source
- EU Verordening 853/2004 — Hygiënevoorschriften voor levensmiddelen van dierlijke oorsprong (2004) — Official source
- EU Verordening 1169/2011 — Voedselinformatie aan consumenten (2011) — Official source
- NVWA — Hygiënecode voor de horeca (2024) — Official source
- NVWA — Allergenen in voedsel (2024) — Official source
- Codex Alimentarius — International Food Standards (2024) — Official source
- FSA — Safer food, better business (HACCP) (2024) — Official source
- BVL — Lebensmittelhygiene (HACCP) (2024) — Official source
- Warenwetbesluit Bereiding en behandeling van levensmiddelen (2024) — Official source
- WHO — Foodborne diseases estimates (2024) — Official source
Food Standards Agency (FSA) — https://www.food.gov.uk
The HACCP standards shown in this application are for informational purposes only. KitchenNmbrs does not guarantee that displayed values are current or complete. Always consult the FSA or your local authority for the latest regulations.
Written by
Jeffrey Smit
Founder & CEO of KitchenNmbrs
Jeffrey Smit built KitchenNmbrs from 8 years of hands-on experience as kitchen manager at 1NUL8 Group in Rotterdam. His mission: give every restaurant owner control over food cost.
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