Growing Cucumbers in a Greenhouse: A Complete Guide

Cucumbers are a popular vegetable that add a fresh, crispy element to salads, sandwiches, and more. While they grow well outdoors, cucumbers also thrive when cultivated in a greenhouse environment The controlled setting allows you to grow delicious cucumbers throughout the season If you’re wondering “can you grow cucumbers in a greenhouse?”, the answer is a resounding yes! Here is a complete guide to successfully raising cucumbers hydroponically or in grow bags inside your greenhouse.

Overview of Cucumber Plants

Cucumbers (Cucumis sativus) are a widely cultivated vining vegetable belonging to the Cucurbitaceae or gourd family. The plants produce cylindrical green fruits that are eaten fresh or pickled.

Most cucumber varieties require a long warm growing season and are sensitive to frost. They prefer consistent moisture and soil pH between 6.0-7.0. Cucumber vines can sprawl 6 feet or more across the garden.

There are three main types of cucumbers suitable for indoor greenhouse growing

• Slicing cucumbers – Standard larger fruits for fresh eating and salads.

• Pickling cucumbers – Shorter and blocky for pickling into dills, gherkins, etc.

• English or gourmet cucumbers – Long, thin, and nearly seedless.

Many compact bush or dwarf varieties are also ideal for containers and smaller greenhouse spaces.

Benefits of Growing Cucumbers in a Greenhouse

Cucumbers grow exceptionally well in greenhouse environments. Here are some key advantages:

• Extended season – Grow cucumbers earlier and longer than outdoors.

• Frost protection – Maintain optimal warm temperatures inside.

• Pest protection – Prevent insect damage under cover.

• Space efficiency – Grow vertically with trellising to maximize area.

• Soil control – Carefully manage moisture and nutrients.

• Plant protection – Shelter seedlings and transplants.

A greenhouse allows you to grow cucumbers for months past the normal outdoor range. You also avoid pest and disease issues common when growing cucumbers outside.

Selecting Greenhouse Cucumber Varieties

Many cucumber cultivars are bred specifically for optimized greenhouse performance. Ideal greenhouse varieties include:

• Mini cucumbers – ‘Mini Munch’, ‘Picklebush’, etc.

• English or European – ‘Diva’, ‘Passandra’, ‘Cumlaude’

• Bush or dwarf – ‘Fanfare’, ‘Salad Bush’, ‘Vert Petit’

• Parthenocarpic – ‘Green Fingers’, ‘Sucy’, ‘Corinto’

• Slicers – ‘Tasty Green’, ‘Sweet Slice’, ‘Burpless’

• American picklers – ‘Calypso’, ‘Carolina’

Look for varieties resistant to powdery mildew, cucumber mosaic virus, and other common diseases when growing in an enclosed greenhouse space.

Growing Cucumbers Hydroponically in a Greenhouse

One excellent method for greenhouse cucumbers is hydroponic cultivation. Here are tips:

• Start seeds in propagation cubes then transplant into net pots filled with a well-drained medium like perlite or vermiculite.

• Place net pots into holes cut in the lid of a hydroponic reservoir to suspend plants above the nutrient solution.

• Use an hydroponic nutrient formula diluted to strength recommended for cucumbers. Maintain optimal pH and EC.

• Consider a top-feed DWC system for easiest management of nutrients and water.

• Train vines vertically using strings, cages, or trellises. Prune aggressively.

• Provide consistent warm temperatures around 75°F. Ensure high humidity levels.

Follow general hydroponic guidelines for cucumbers, providing plenty of light, pruning vines, and monitoring the reservoir solution.

Growing Cucumbers in Grow Bags in a Greenhouse

Grow bags are another excellent method for greenhouse cucumbers. Follow these tips:

• Fill 10-15 gallon grow bags half full with a lightweight potting mix amended with compost or coir.

• Sow 2-3 seeds per bag, thinning later to the strongest seedling.

• Water when top inch of soil feels dry. Use a liquid fertilizer per package rates every 2-3 weeks.

• Train vines up strings attached to overhead supports. Prune side shoots for best fruiting.

• Pollinate female flowers by gently shaking vines daily if no pollinators have greenhouse access.

• Monitor for common pests like aphids and diseases like powdery mildew.

Ensure grow bags are placed in full sun and have drip trays underneath to prevent waterlogging. Trellising vertical saves space and supports heavy yields.

Caring for Greenhouse Cucumbers

Once seeded or transplanted, greenhouse cucumbers need:

• Daytime temperatures of 75-85°F, around 60°F at night. Provide a heat source if needed.

• Consistent moisture in the root zone, allowing soil to partially dry between waterings.

• Moderate fertilization with a balanced liquid plant food or in hydroponic solutions.

• Plenty of direct sunlight for at least 8 hours daily. Supplement with grow lights if light levels are low.

• Good air circulation from fans to strengthen plants and prevent fungal disease.

• Vertical supports for vining varieties to grow upwards. Prune off side shoots for best fruiting.

Monitor plants closely for pests like whiteflies and diseases like powdery mildew. Take corrective action promptly in the enclosed greenhouse space.

When to Harvest Greenhouse Cucumbers

Cucumbers are ready for picking when:

• Fruits are firm, crisp, and bright green (or variety color)

• Cucumbers reach ideal size for the variety, usually 6-8 inches long

• Skin is thin and free from blemishes, pits, yellowing, etc.

• Seeds inside are still soft before full maturation

• Flower end is rounded, not pointed

Use a sharp knife or pruners to carefully snip cucumbers from vines, retaining some stem. Handle gently to avoid bruising. Harvest frequently to encourage more fruit production.

Expected Cucumber Yield Per Plant

A single healthy cucumber plant grown in optimal greenhouse conditions can yield:

• 10-25 fruits per bush or dwarf variety

• 25-100 cucumbers per vining plant

Actual yields depend on greenhouse space, training method, pruning technique, and cultivar planted. Trellised vining plants spaced efficiently will achieve the highest productivity.

Troubleshooting Common Cucumber Problems

Growing cucumbers in a greenhouse avoids many outdoor issues but problems can still arise.

• Slow growth – Ensure daytime temperatures of at least 75°F and provide supplemental lighting if inadequate sunlight.

• Flowers falling off – Improve pollination by shaking vines daily to distribute pollen. Low humidity causes flower drop.

• Misshapen fruits – Insufficient pollination leads to oddly-shaped cucumbers.

• Bitter taste – Overripe fruits turn bitter. Harvest regularly at proper younger stages.

• Powdery mildew – Improve air circulation and reduce humidity levels. Use sulfur fungicides if severe.

Monitor closely and quickly remedy any issues for best greenhouse cucumber health and productivity.

Storing the Harvest from Greenhouse Cucumbers

Freshly picked greenhouse cucumbers will store:

• 1 week when refrigerated in a plastic bag

• Up to 5 days at cool room temperature

• Several months when pickled, fermented, frozen, or canned

Enjoy cucumbers immediately after harvest for premium flavor and texture. The skins do not need peeling unless preferred. Rinse under cool water before eating or processing.

Top Tips for Greenhouse Cucumber Success

Follow these tips for achieving thriving cucumber plants with heavy yields:

• Select varieties optimized for greenhouse growing like ‘Diva’, ‘Fanfare’, etc.

• Maintain warm day and night temperatures around 75-80°F.

• Prune and trellis vines vertically to save space and improve fruiting.

• Pollinate female flowers by gently shaking plants daily.

• Use hydroponics or quality potting mix in grow bags.

• Irrigate consistently and fertilize plants weekly.

• Harvest ripe fruits frequently to encourage more production.

With the right practices, a greenhouse provides ideal growing conditions to generate abundant cucumbers season after season.

FAQs about Growing Cucumbers in a Greenhouse

Can you successfully grow cucumbers year round in a greenhouse?

Yes, with supplemental lighting and heat, greenhouse cucumbers can produce all year. Productivity declines in winter but greenhouse conditions extend the season compared to outdoors.

Is pollination needed for greenhouse cucumber plants?

In most cases, pollination is needed to produce the fruits, unless planting parthenocarpic varieties. Indoor bees or manually shaking vines distributes pollen to female flowers.

How much space do cucumber vines need in a greenhouse?

Bush types need 1 square feet. For vining plants, allow 3 square feet when trained vertically. Ramps or overhead support structures maximize space efficiency.

Is it better to grow cucumbers in containers or hydroponically in a greenhouse?

Both methods work well. Hydroponics offers more control but containers with a quality potting mix are lower maintenance. Ensure adequate support either way.

Conclusion

Cucumbers are a rewarding vegetable to add to your greenhouse. When provided with ample warmth, light, vertical supports, and proper care, cucumber plants will flourish in a greenhouse. Both dwarf potted plants and vertically trained vining plants produce abundantly within the protected confines of a greenhouse. With so many varieties optimized for greenhouse culture, it’s easy to enjoy fresh cucumbers direct from your indoor garden.