Vegetables
Senior 1 · Agriculture
Vegetables
Lesson 4 of 5
20 min
Let's begin
Pick a cabbage too early and the head is loose and light; pick it too late and it splits open in the rain. Tomatoes picked fully red for a market three days away arrive soft and bruised; picked just as they turn pink, they arrive perfect.
Every vegetable shows signs, called maturity indicators, that tell you when it is ready. Harvesting at the right moment, and in the right way, decides how much of your crop reaches the buyer in good condition.
| Vegetable | Ready when… | Too late if… |
|---|---|---|
| Tomato | Colour begins to change from green to pink (for distant markets) or is fully red (for home use or a nearby market); still firm | Soft, cracked or overripe |
| Cabbage | Head is firm and compact when pressed | Head splits |
| Cauliflower | Curd (white head) is compact and white | Curd loosens, turns yellow or "ricey" |
| Onion (dry bulbs) | Most of the tops (leaves) have turned yellow and fallen over | Bulbs start to sprout or rot in wet soil |
| Carrot | Roots have reached usable size (shoulders about 2 to 3 cm across) | Roots become woody or split |
| Amaranth leaves | Young, tender leaves before flowering; pick every week or two, or uproot young plants | Plants flower and leaves turn tough and bitter |
| Eggplant | Skin is glossy and firm, seeds still soft | Skin turns dull, seeds harden and turn brown |
| French beans | Pods snap cleanly and seeds inside are still small | Pods become stringy and seeds bulge |
| Cucumber | Green, firm and of full size | Turning yellow |
| Pumpkin | Rind is hard and cannot be dented with a fingernail; stalk dry | Rots in the field |
Question: A tomato variety is ready about 75 days after transplanting. Seedlings are transplanted on 10 March. On what date does harvesting begin?
Days left in March after the 10th: 31 − 10 = 21. Remaining: 75 − 21 = 54 days.
April has 30 days: 54 − 30 = 24 days into May.
Harvest begins about 24 May.
Question: A farmer harvests 1,200 kg of tomatoes, but 15% are bruised or crushed and cannot be sold. The price is 400 Frw per kg (illustrative). (a) How many kilograms can be sold? (b) How much money is lost?
(a) Lost = 0.15 × 1,200 = 180 kg. Sold = 1,200 − 180 = 1,020 kg.
(b) Money lost = 180 × 400 = 72,000 Frw, earned by growing the crop and then thrown away by careless handling.
Tip
Memory hook for harvest indicators: "Size, Shade, Squeeze, Skin, Stalk": size, colour, firmness, skin or pod texture, and drying leaves or stalk.
Exam technique: name the indicator for the SPECIFIC vegetable asked. "When it is mature" earns nothing; "when the onion tops yellow and fall over" earns the mark.
State the harvesting indicator for (a) cabbage, (b) onion, (c) eggplant.
Solution: (a) Head firm and compact when pressed. (b) Most tops have yellowed and fallen over. (c) Skin glossy and firm, seeds still soft.
Why are tomatoes for a distant market picked as they start to turn pink rather than fully red?
Solution: They continue ripening after picking, so they reach the market ripe but still firm, and are less easily bruised on the journey.
Give three good practices when harvesting vegetables.
Solution: Any three: harvest in the cool morning; avoid wet produce; observe the pre-harvest interval; use clean sharp tools; handle gently; use ventilated crates; keep in shade; sort and grade.
Cabbage is ready 90 days after transplanting on 1 February (not a leap year). On what date is it ready?
Solution: Days left in February after the 1st: 28 − 1 = 27, leaving 90 − 27 = 63. March has 31: 63 − 31 = 32. April has 30: 32 − 30 = 2. Ready about 2 May.
800 kg of cabbage is harvested and 10% is damaged. At 250 Frw per kg (illustrative), how much money is lost?
Solution: Lost = 0.1 × 800 = 80 kg. 80 × 250 = 20,000 Frw.
Summary
Sources and credits
This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.
