Cucumbers – salad, pickling, and snake varieties

Cucumbers – Salad, Pickling, Mini Varieties

Sown cucumber (Cucumis sativus) is the second most cultivated vegetable in Czech gardens after tomatoes. Crispy, refreshing, and irreplaceable – whether in salads, for pickling, or straight from the plant. Growing cucumbers is not complicated, but this crop has clearly defined requirements: it loves warmth, plenty of moisture, and nutrient-rich soil. Those who meet these conditions harvest continuously from July through September.

1. Cucumber Types

Salad Cucumbers

Long, smooth fruits (20–35 cm) with thin skin, intended for direct consumption – in salads, sandwiches, or as a side dish. Best quality is achieved in a greenhouse or cold frame, where even warmth and protection from rain are guaranteed. Modern varieties are typically parthenocarpic – they fruit without insect pollination, which is a key advantage in a greenhouse environment.

Proven varieties: Marketmore (tolerates outdoor conditions), Telegraph Improved, Dominica F1, Pony F1.

Pickling Cucumbers (Gherkins)

Smaller fruits (6–12 cm) with thicker, warty skin and firmer flesh that withstands heat processing. They are harvested young and preserved in salty or vinegar brine – classic Czech pickles. They are grown exclusively outdoors because they need insect pollination to fruit, especially by bees.

Proven varieties: Český nakládací, Libela F1, Othello F1, Parisian Pickling.

Mini Varieties

A practical compromise between salad and pickling types. Fruits measure 15–20 cm, the skin is thin with fine warts. They are suitable for both direct consumption and preserving. They can be grown outdoors or in a greenhouse, and for beginning growers they represent an easy entry into cucumber growing.

Proven varieties: Picolino F1, Iznik F1, Baby Star.

Special Types

• Armenian Cucumber: Very long, S-shaped curved fruits. Botanically belongs to melons but has a striking similarity to cucumber in taste. Requires high heat and a longer growing season.
• Lemon Cucumber: Round, yellow fruit the size of a lemon with delicate, mildly sweet flavor. Decorative and easy to grow.
• Asian Cucumbers: Long, ridged, distinctly crispy. Heat-loving, suitable for a greenhouse or plastic tunnel.

2. Seedlings vs. Direct Sowing

Unlike tomatoes or peppers, you have a choice with cucumbers – you can grow seedlings at home or sow directly in the bed. Both methods have their merit.

Seedling Growing (Container Sowing)

When: Mid-April through early May.

Process:
1. Sow into individual pots or peat pots. Cucumbers are very sensitive to root disturbance – transplanting from larger containers is risky.
2. Sowing depth: 1–2 cm, one seed per pot.
3. Germination temperature: 22–28 °C. Below 15 °C seeds do not germinate, below 10 °C development stops completely.
4. Germination: 3–7 days at correct temperature.
5. Grow seedlings in a warm, brightest location for 3–4 weeks. Supplementation with LED lighting significantly reduces stretching toward light.
6. Transplanting outdoors: Only after the last frost, from mid-May onward. Transplant with the entire root ball, ideally on a cloudy day or in the evening.

Advantage: Harvest occurs 2–3 weeks earlier compared to direct sowing.

Direct Sowing in the Bed

When: Mid-May through mid-June (soil must maintain at least 15 °C – check with a thermometer at 4 inches depth).

Process:
1. Sow in groups – 3–4 seeds together, depth 2–3 cm.
2. Group spacing: 24–32 inches (gherkins), 32–40 inches (salad varieties).
3. After sprouting, keep 1–2 strongest plants in each group and remove others or pinch them off – don't pull them as this may damage neighboring roots.

Advantage: Simpler process, no risk of root damage during transplanting. Plants from direct sowing are often more resilient to weather fluctuations.

Disadvantage: Harvest occurs 2–3 weeks later. Young seedlings are threatened by slugs; protect from the start.

3. Site Requirements

Warmth

Cucumbers are among the most heat-demanding vegetables in our conditions. The minimum temperature for active growth is 59 °F (15 °C), optimal range is 72–82 °F (22–28 °C). Below 54 °F (12 °C) plants practically stop growing, below 46 °F (8 °C) permanent damage threatens. Nighttime temperature should not consistently drop below 59 °F (15 °C).

In cooler regions or mountainous areas, a greenhouse or plastic tunnel is almost essential for salad varieties – without protection the season is often too short for reliable harvest.

Soil

Cucumbers require rich, humus-abundant, well-draining soil with the ability to retain moisture but without risk of permanent waterlogging. Ideal pH ranges from 6.0–7.0.

Before planting, work large amounts of mature compost or decomposed manure into the soil. A time-tested and still-effective method is planting on a manure bed – a raised bed of semi-decomposed manure that provides bottom heat to roots and continuously releases nutrients. With this growing method, cucumbers literally explode in production.

Light

Full sun for at least 6–8 hours daily. In shade cucumbers grow vegetatively but fruit minimally or not at all. Choose a site protected from cold north winds.

Moisture

Cucumber fruits are over 95% water – and their requirements for irrigation correspond exactly to that. Plants need continuous, even moisture in the soil. Fluctuations between drying out and waterlogging cause bitter fruit, deformation, and increase susceptibility to disease.

4. Cucumber Care

Irrigation

Irrigation is the most important cultivation practice for cucumbers and the most common cause of disappointment from careless management.

• Frequency: In normal weather daily or every other day, in summer heat even twice daily.
• Amount: 3–5 liters per plant daily during peak fruiting – in a hot week you can easily calculate how much water one bed consumes.
• Method: Water at ground level, ideally with warm, settled water. Cold well water causes root temperature shock and slows nutrient uptake. Never water onto leaves – wet leaves are ideal for powdery mildew development.
• Drip irrigation is the best possible solution for cucumbers – it maintains constant moisture, conserves water, and completely eliminates wet foliage.

Mulching

Mulching fundamentally affects the season's results for cucumbers. Lay a 2–4 inch layer of straw, cut grass, compost, or use non-woven fabric.

Properly applied mulch serves several functions:
- Maintains even moisture and prevents rapid surface drying.
- Prevents temperature fluctuations in the root zone.
- Suppresses weeds and saves maintenance time.
- Protects fruits from direct soil contact and associated rot.
- Limits overheating of the shallow root system during summer heat.

Fertilizing

Cucumbers are highly demanding for nutrients and regular fertilizing throughout the season is essential – without it they quickly exhaust their basic reserves and stop fruiting.

• Base fertilizing: Compost and manure worked into the soil before planting form the foundation of nutrition.
• In-season fertilizing: Every 10–14 days with liquid fertilizer with balanced nutrient ratio. Nettle extract or fermented compost water are excellent organic alternatives.
• During peak fruiting, switch to fertilizer with higher potassium content – it supports fruit formation and quality and increases plant stress tolerance.
• Nutrient deficiency reliably shows as yellowing of older leaves, weak growth, and deformed fruits.

Supports and Training

Pickling cucumbers are traditionally left to sprawl on a mulched bed surface. Training on a vertical net or wire structure brings cleaner fruits, easier harvest, and better bed organization.

Salad cucumbers in a greenhouse should be trained on string or vertical net. Space savings, better air circulation, and clarity are key advantages in greenhouse cultivation.

Mini varieties adapt to both methods – on the ground or on supports.

Pinching

• Salad cucumbers in greenhouse: Train the main stem vertically up the string and regularly wrap or tie it. Cut side shoots to 1–2 leaves past the first fruit. When the plant reaches the ceiling, bend it and let it continue downward – this extends the harvest period.
• Pickling cucumbers outdoors: Typically left unpruned. If the plant becomes overly vegetative at the expense of fruiting, shorten the longest side shoots above the third leaf.

5. Diseases and Pests

Powdery Mildew (Podosphaera xanthii, Erysiphe cichoracearum)

Most common cucumber disease in the Czech Republic. Appears as white, powdery coating first on the upper side of leaves. Gradually affects the entire aboveground part, leaves yellow, dry, and the plant loses photosynthetic area – harvest decreases significantly.

Prevention:
- Maintain adequate spacing and ensure air circulation around plants.
- Never water onto leaves, especially in afternoons and evenings.
- Choose varieties with declared mildew tolerance – most modern hybrids offer it.
- Preventive sprays from the beginning of growth: horsetail extract, milk solution (1 part milk to 9 parts water), sulfur-based products.

When infection occurs:
- Remove and destroy heavily infested leaves (do not compost).
- Apply fungicide – Bacillus subtilis is effective among biological products.
- If infection occurs late in September at season's end, focus on harvesting remaining fruits and thoroughly remove the crop afterward.

Downy Mildew (Pseudoperonospora cubensis)

Manifests as oily yellow spots bounded by veins on the upper side of leaves and grayish-violet coating on the underside. Spreads very rapidly in humid, warm weather – in such a year it can destroy a crop in just two weeks.

Prevention: Plant spacing, watering without wet leaves, selection of tolerant varieties, preventive copper-based sprays.

Cucumber Mosaic Virus (CMV)

Leaves are twisted, deformed, with characteristic mosaic pattern in multiple shades of green. Fruits are bumpy, deformed, and inedible. The pathogen is transmitted by aphids; no effective chemical protection exists against the virus. Remove and destroy infested plants outside the compost area.

Pests

• Aphids: Transmit viral diseases and weaken plants through feeding. Support natural predators (ladybugs, lacewings); at high levels use soap or oil spray.
• Spider Mites: Fine webbing on leaf underside, light spotting, progressive leaf drying. Most common in greenhouses in dry conditions. Regularly increase air humidity; at high levels introduce biological control (Phytoseiulus persimilis).
• Slugs: Threaten freshly transplanted seedlings. Protection: wood ash or gravel as barriers, beer traps, ecological granules with iron phosphate.
• Leaf Miners: Larvae tunnel characteristic galleries in leaf tissue. Remove and destroy infested leaves.

6. Why Are Cucumbers Bitter?

Bitter taste is caused by cucurbitacin, naturally present in the skin and stem end of the fruit. Modern varieties have significantly reduced cucurbitacin through breeding, but any plant stress triggers increased production.

Most common causes of bitterness:
- Irregular irrigation – alternating between dry and waterlogged periods.
- Excessively high daytime temperatures (above 95 °F / 35 °C) or conversely low nighttime temperatures.
- Nutrient deficiency, especially potassium.
- Delayed harvest and overripe fruits.

Practical solution: Mulching and regular irrigation are the most reliable prevention. If a particular fruit is nonetheless bitter, cut off the stem end (2 inches) and peel the skin – the inner flesh usually suffers less or not at all from bitterness.

7. Harvesting

When and How to Harvest

Pickling Cucumbers:
- Harvest daily or every other day without fail. Gherkins grow incredibly fast in summer heat – in 2–3 days an ideal 3-inch fruit becomes overgrown and seedy, unsuitable for preserving.
- Optimal harvest size: 2.5–4 inches for classic pickling, 1.2–2 inches for French style (cornichons).
- Immediately remove overgrown and forgotten fruits – the plant invests energy in them at the expense of new fruit formation.

Salad Cucumbers:
- Harvest at 8–12 inches length while fruits are dark green, firm, and skin is smooth.
- Overripe fruits yellow, seeds coarsen, flesh becomes watery and bland.

Mini Varieties:
- Harvest at 6–8 inches length when fruits are still firm and taste best.

Yield

• Gherkins: 6.5–13 lbs per plant over the season with daily harvest.
• Salad varieties: 11–22 lbs per plant, in heated greenhouse often significantly more.
• Mini varieties: 6.5–11 lbs per plant.

Harvest Duration

Outdoor cucumbers fruit from July through the first September nights below 50 °F (10 °C). Greenhouse varieties can, with good management, be harvested from June through October. Regular and thorough harvesting is the most effective way to extend fruiting of the entire crop.

8. Greenhouse vs. Outdoor Cucumbers

Greenhouse

• Suitable varieties: Salad cucumbers, mini varieties, special types.
• Advantages: Earlier and longer harvest period, protection from rain, cold and leaf diseases, significantly higher yields.
• Pay attention to: In summer heat there's risk of overheating – ventilate intensively and timely. Spider mites thrive in dry greenhouse conditions; maintain air humidity. Irrigation is entirely your responsibility; automation pays for itself.
• Parthenocarpic varieties are ideal for greenhouse – they produce fruit without insect presence.

Outdoor Bed

• Suitable varieties: Pickling cucumbers (require bee pollination), hardy salad varieties (Marketmore and similar).
• Advantages: Natural pollination, smaller infrastructure investment, simpler ventilation.
• Disadvantages: Weather-dependent, higher risk of leaf disease in rainy summers, shorter harvest period.

Tip: Plastic Tunnel

An ideal compromise for most gardeners. A plastic tunnel protects from rain and night frosts, increases ambient temperature, and extends the season – for a fraction of the cost of a permanent greenhouse. Both gherkins and salad varieties in a tunnel significantly outperform outdoor results.

9. Frequently Asked Questions (FAQ)

Why aren't my cucumbers fruiting?
Most common causes: insufficient pollination (traditional varieties in outdoor bed), temperature below 59 °F (15 °C), depleted or poor soil, overcrowded plants without enough light and air. Check irrigation, nutrient supply, and thin the planting if necessary.

Can I grow cucumbers next to tomatoes?
In a greenhouse this combination works, but involves compromises – cucumbers require higher air humidity, tomatoes don't tolerate it. If there's no other option, separate them on opposite sides of the greenhouse and ventilate continuously.

Why do fruits twist and deform?
Irregular irrigation, potassium deficiency, incomplete pollination (some seeds didn't develop, fruit is asymmetrical), or temperature too low during flowering. Most often a combination of the first two causes.

Can I collect seeds from F1 hybrid varieties?
Technically yes, but seeds won't produce plants identical to the parent – offspring is often highly variable. It doesn't pay to collect F1 hybrid seeds; get fresh seeds from a reliable supplier each year.

How do I prevent slugs?
Barrier of wood ash or crushed stone gravel around the bed, copper tape, beer traps buried in the ground, and ecological granules with iron phosphate. Hand collection early morning or after rain is surprisingly effective on small plots.

What do I do with overgrown cucumbers?
Peel large gherkins, remove seeds, and coarsely grate into cucumber salad with sour cream. Overgrown salad cucumbers are suitable for soups, cold creams, or as the base for vegetable smoothies.

10. Cucumber Growing Calendar for the Czech Republic

Summary

Cucumbers are a quick and rewarding crop – from sowing to harvest takes 50–70 days. Success is based on warmth (minimum 59 °F / 15 °C, ideally 72–82 °F / 22–28 °C), regular and abundant irrigation, nutrient-rich and well-mulched soil, and consistent fertilizing throughout the season. For gherkins choose proven Czech varieties, harvest daily, and don't let any fruit overgrow. For salad cucumbers, investment in a greenhouse or plastic tunnel pays back many times over – in season length and yields. And don't forget powdery mildew prevention: spacious site, watering at ground level, and tolerant varieties are the cheapest and most reliable defense at your disposal.