For a greengrocer, profit usually slips away on the buying side, not the selling side. Tomatoes might cost 2.20 per kg at the wholesale market on Monday, 2.80 on Wednesday and 1.90 on Friday, while the label on the shelf is written once and stays the same for days. The result is familiar: the till looks busy every evening, yet at the end of the month nobody can explain where the money went. This guide sets out a practical routine for greengrocer price tracking and profit calculation: recording wholesale purchases properly, reviewing prices against cost every day, handling sales by weight and by the piece with the same logic, seeing gross profit per product, comparing suppliers and running a short weekly profitability check. Figures below are examples and work in any currency.
Why gut feeling doesn't work in a produce shop
In a corner shop or a stationery store, the purchase price of an item can stay the same for weeks or months. In a greengrocer you start every morning with a new cost. And that cost is not a single number: on top of the price per kilo you pay commission, porterage, transport and the occasional unreturned crate. Some of the stock will also spoil before it sells. That is why margin leaks out in three places:
- Old label, new cost: the buying price goes up but the selling price stays at yesterday's level, and the margin quietly shrinks.
- Incomplete cost: only the market price per kilo is counted; transport and porterage are treated as "overheads" and never loaded onto the product.
- Looking only at turnover: a strong day at the till feels like a good day, but the products that bring in sales are often not the ones that bring in profit.
Closing these gaps does not require accounting skills. It takes a simple recording habit done in the same order every morning and a short check once a week.
Step 1: Record wholesale purchases properly
An accurate profit figure starts with an accurate purchase record. When you get back from the wholesale market or your supplier, record the following for each product:
- Supplier: which trader or wholesaler you bought from.
- Net quantity: kilos after deducting the crate weight, or the number of pieces. Compare the quantity on the invoice with what you actually received.
- Unit purchase price: the price per kilo or per piece on the invoice.
- Extra costs: commission, porterage, transport and any crate deposits you won't get back.
- Payment status: paid on the spot or put on account?
Spreading extra costs across products
The most common mistake is leaving transport and porterage out of product cost. A simple method: divide that morning's total extra costs by the total purchase value and apply the same percentage to every product.
Example: one morning you buy produce worth 1,200 in total. Transport, porterage and commission come to 96. The extra-cost rate is 96 / 1,200 = 8%. Tomatoes bought at 2.40 per kg therefore really cost 2.40 × 1.08 = 2.59, or roughly 2.60. When you set the shelf price, that is the figure to work from, not 2.40.
Heavy but cheap items such as potatoes, onions and watermelons actually carry a bigger share of transport cost. If that matters to you, spread extra costs by weight instead of by value; for most shops, spreading by value is an accurate enough starting point.
Step 2: A daily price review routine
If cost changes every day, price needs reviewing every day. That doesn't mean changing every price daily, but it does mean looking at every price daily. After the morning buy, run this 15-minute routine:
- Work out the new cost: unit purchase price including extra costs.
- Account for leftover stock: if yesterday's produce is still on hand, calculate the average cost (example below).
- Apply your target margin: use the target gross margin you set for the product group to find the selling price.
- Round and look around: round to a price customers can read at a glance, and keep local competitors and the market stall down the road in mind.
- Update the till and the label together: the shelf label, the scale and the till must show the same price. Forget one and you get either a complaint or a lost margin.
Average cost example
Example: you have 40 kg of cucumbers left from yesterday at a real cost of 2.20 per kg. Today you buy another 100 kg at a real cost of 2.60. Average cost: (40 × 2.20 + 100 × 2.60) / 140 = (88 + 260) / 140 = 2.49. With a 35% target gross margin the selling price is 2.49 / (1 − 0.35) = 3.83, which you round to 3.79 or 3.85. Pricing only from today's buy (say 4.00) may put customers off; pricing only from yesterday's (3.40) eats into profit.
Margin or markup?
These two are often mixed up. Adding 35% on top of cost (2.60 × 1.35 = 3.51) is not the same as making 35% of the selling price profit (2.60 / 0.65 = 4.00). Decide which one you use and apply it to every product; otherwise your reports won't add up. In this guide, "gross margin" always means the share of the selling price.
Step 3: Treat sales by weight and by the piece the same way
Some produce sells by the kilo (tomatoes, apples, potatoes), some by the piece (lettuce, watermelon, pineapple) and some by the bunch (parsley, dill, rocket). The trouble usually starts when you buy in one unit and sell in another: lettuce arrives by the crate but leaves by the head.
- Convert the purchase unit into the selling unit: if a crate holds 12 lettuces and costs 21.60 including extras, each head costs 21.60 / 12 = 1.80.
- Pick one unit: if you sell the same item both by weight and by the piece (watermelon, for instance), set up two separate product records or settle on one unit. Booking two units against one record throws both stock and profit off.
- Allow for trimming on bunched herbs: count how many bunches you get from a bundle a few times, take the average and cost each bunch from that.
For sales by weight, scale barcodes make the till faster and more accurate: the scale prints weight and price into a barcode, and when it is scanned the amount goes onto the receipt without anyone typing it. No more "I rang up 4.00 but said 3.80", and the kilos sold come off stock correctly.
Step 4: See gross profit per product
Gross profit is what is left of sales after deducting the real cost of the goods. Rent, energy and wages come after that. In a produce shop you need gross profit per product first, because it is the figure that tells you what to buy more of and what to cut back.
An example weekly table (figures are illustrative):
| Product | Sold | Avg. selling price | Real cost | Gross profit | Gross margin |
|---|---|---|---|---|---|
| Tomatoes | 420 kg | 3.80 | 2.60 | 504 | 32% |
| Potatoes | 600 kg | 1.80 | 1.40 | 240 | 22% |
| Bananas | 150 kg | 2.10 | 1.55 | 83 | 26% |
| Lettuce | 180 pcs | 3.00 | 1.80 | 216 | 40% |
| Parsley | 250 bunches | 1.00 | 0.40 | 150 | 60% |
A table like this tells you a lot at once. Potatoes are among the best sellers but earn little per kilo; once shelf space and transport are considered, they are not your main source of profit. Parsley looks like a small line yet has one of the highest margins, so it deserves a spot at the front of the counter at eye level. Tomatoes bring both volume and profit; every 0.10 change in their buying price moves your week noticeably, which is why they come first in price tracking.
Spoilage changes the picture. Gross profit calculated on quantity sold ignores what ends up in the bin. If 8% of the week's tomato purchases spoiled, real cost rises to 2.60 / 0.92 ≈ 2.83 per kg and the gross margin drops from 32% to about 26%. Recording waste is a topic of its own, but it must feed into your profit figures: if spoiled produce isn't logged every evening, the table shows more profit than you really made.
For the broader logic of per-product profit and the 80/20 approach, see our product-level profitability analysis guide.
Step 5: Compare suppliers on the right number
One trader at the market may sell tomatoes at 2.20 per kg and another at 2.40. The cheaper one is not always the more profitable one. Compare on cost per sellable kilo, not on the invoice price.
Example:
- Trader A: 2.20 per kg, but the bottom layer of the crates is often bruised, with about 12% lost to sorting. Cost per sellable kilo: 2.20 / 0.88 = 2.50.
- Trader B: 2.40 per kg, consistently good quality, about 3% loss. Cost per sellable kilo: 2.40 / 0.97 = 2.47.
B looks more expensive on paper but is cheaper on the shelf. Good produce also lasts longer and keeps customers happy. To make this comparison all you need is to record the supplier on every purchase and note the sorting loss for a few weeks.
Alongside price, keep a note of:
- Payment terms and how reliably the account is kept
- Consistency on crate returns and tare weights
- Whether they reliably stock the varieties you need
- Whether invoiced quantities match what is delivered
Track what you owe each trader and wholesaler in the same place. Knowing your outstanding balances is part of planning the week's cash. For a wider framework on choosing and negotiating with suppliers, read our article on supplier selection and management.
Step 6: A weekly profitability check
The daily routine keeps prices right; the weekly check keeps the direction right. Set aside 30 minutes on the same day each week, for example Monday morning before you go to market, and work through this checklist:
- Total gross profit and margin: what were last week's sales, real cost of goods and gross margin? Compare with the week before.
- Top 10 products: list the ten products with the highest gross profit. These deserve priority in buying and on the shelf.
- Products with falling margins: flag anything below target. Is it the buying price, a label nobody updated, or spoilage?
- High-waste lines: where waste exceeds a threshold you set (say 10%), consider buying less.
- Supplier notes: whose produce lost the least to sorting? Write it into next week's buying plan.
- Till versus records: does the weekly till total match recorded sales? If not, look at manually keyed sales and refunds.
Do this four weeks in a row and you will see clearly which products carry the shop and which only fill the shelves.
Common mistakes
- Pricing against competitors without checking cost: the shop down the road may buy cheaper; their price could be your loss.
- Updating the label but not the till: customers expect the shelf price; if the till charges the old one, you either lose trust or absorb the difference.
- One margin for everything: applying the same rate to fast-wilting herbs and long-keeping onions means too much profit on one and too little on the other.
- Not recording purchases on account: if credit purchases are not entered, cost looks lower and profit looks inflated.
- Skipping the weekly check because it's busy: the busiest weeks are often the ones where the most margin is lost.
From notebook to software: when to switch
All of these routines can be done with a notebook and a calculator. But once you have 80 to 100 lines, prices changing daily and several suppliers, manual calculation takes longer and errors creep in. With dedicated greengrocer software, most of these steps are recorded as part of the normal working day.
With Welda Stock, for example, you enter what you bought at the wholesale market against the supplier's invoice; because purchase prices are recorded, your per-product margin is updated, and the amount you owe each supplier is recorded too. You update changing prices in bulk, and sales are always posted at the current price. Weight/price barcodes printed by the scale are decoded automatically at the till, and items sold by the piece are added by barcode. When you log spoiled produce as waste in the evening, the end-of-day report and per-product profit reports reflect what really happened. You can find the details on our page about stock and till software for greengrocers.
For how to record waste and tie it to daily buying quantities, see our guide to greengrocer waste and spoilage.
Frequently Asked Questions
Do I have to change greengrocer prices every day?
You don't have to change every price every day, but you should check them every day. Update prices on items whose cost has moved noticeably (often tomatoes, peppers and fruit); for items with stable cost, such as potatoes and onions, you can keep the label. What matters is that the decision is based on today's cost rather than a guess.
What is a good gross margin for a greengrocer?
There is no single right figure; it depends on the product group, your area and your waste rate. A practical approach is to set different targets per group: higher for fast-perishing herbs and soft fruit, lower for long-keeping items. Base your own targets on the real figures from the past few weeks and always factor in waste.
Should I add wholesale market transport to product cost?
Yes. Transport, porterage and commission are part of getting the produce onto your shelf. Leave them out and every product looks more profitable than it is. The simplest method is to divide the total extra costs by the day's purchase value and spread that percentage across all products.
Can I track items sold by weight and by the piece in one system?
Yes, as long as each product has a clear selling unit. For items bought by the crate and sold by the piece, convert the purchase cost into a per-piece cost; if you sell the same item in two units, set up two product records. Using scale barcodes for sales by weight improves both speed and accuracy.