Cucumber

Cucumis sativus

1. Identification and origin

The cucumber (Cucumis sativus L.) is an annual horticultural species of the Cucurbitaceae family, native to the Himalayan region and the north of India. The crop spread widely throughout Asia and Europe, and is currently cultivated all over the world, both in open field and in greenhouses. In Portugal, it is one of the main greenhouse vegetables.

2. Economic importance

The cucumber is a crop of high commercial importance, standing out for its continuous production, high demand in the fresh market and strong presence in distribution chains. In greenhouses, it allows prolonged harvests and high productivity. It is also used in the canning industry (pickles). The crop has significant economic relevance in producing regions such as the Algarve, the Oeste and the Ribatejo.

3. Botanical characterisation

An annual, herbaceous plant, with a creeping or climbing habit, with tendrils and vigorous growth. The leaves are large, palmate and pubescent. The flowers are yellow, unisexual, with a predominance of male flowers in the early stages. The fruits are elongated, green in colour, and may vary in size and texture according to the cultivar. The root system is superficial, requiring frequent watering.

4. Soil and climate requirements

The cucumber is a warm-climate crop, with ideal temperatures between 22–28 °C. It is sensitive to cold, especially below 12 °C. It prefers light, well-drained soils, rich in organic matter, with a pH between 6.0 and 7.0. The crop requires high water availability and balanced fertilisation, with emphasis on nitrogen, potassium and calcium. High relative humidity favours vegetative development, but also increases the risk of fungal diseases.

5. Main pests

• Whitefly (Bemisia tabaci, Trialeurodes vaporariorum): sap sucking and transmission of viruses
• Aphids (Aphididae): transmission of viruses and leaf deformations
• Mites (Tetranychus urticae): chloroses and leaf necroses
• Thrips (Thysanoptera): silvering and lesions on the fruit
• Soil fly (Bradysia spp.): root damage in seedlings
• Nematodes (Meloidogyne spp.): root galls and vegetative decline

6. Main diseases

• Powdery mildew (Podosphaera xanthii, Erysiphe cichoracearum): white spots and reduction of photosynthesis
• Downy mildew (Pseudoperonospora cubensis): angular spots and necroses
• Root rots (Fusarium oxysporum, Pythium spp.): wilting and death of plants
• Cucumber mosaic virus (CMV): mosaics and deformations
• Cucumber vein yellowing virus (CVYV): chloroses and reduction of productivity
• Anthracnose (Colletotrichum orbiculare): leaf spots and rots on the fruit

7. General crop management

The management of the cucumber includes the use of disease-resistant cultivars, vertical training in greenhouses, adequate ventilation and frequent but controlled watering. Fertilisation should be balanced, avoiding excesses of nitrogen that favour diseases. The control of pests such as whitefly, aphids and mites is essential to avoid significant losses. Harvesting is carried out continuously, when the fruits reach the desired commercial size, avoiding over-ripening.

Bibliographic references

• EPPO Global Database – Cucumis sativus
• CABI – Crop Protection Compendium – Cucumis sativus
• López‑Gálvez, G., et al. (2020). Greenhouse cucumber production. Acta Horticulturae.
• FAO (2021). Protected Cultivation of Vegetables.
• McCreight, J. D., et al. (2019). Diseases of cucurbits. Plant Health Progress.
• Paris, H. S. (2016). Genetics and Breeding of Cucurbits. CRC Press.