Polyhouse Crops: What can be grown in polyhouses?

A polyhouse is a greenhouse covered with polyethylene plastic, creating a controlled space for plants. Polyhouse crops are plants specifically chosen to thrive in this environment. What makes a crop suitable? Ideal candidates are high-value (like veggies, flowers, or herbs), sensitive to weather, and benefit from year-round growing.

The core advantages are game-changers:

Climate Control: Adjust temperature, humidity, and light.

Year-Round Harvests: Grow tomatoes in winter or lettuce in summer.

Higher Yields: Produce 2-10 times more than open fields.

Better Quality: Uniform size, color, and fewer defects.

Less Pests/Diseases: The enclosed space blocks many threats.

Water Savings: Use up to 50-70% less water with drip irrigation.
Focusing on the right crops maximizes your investment and leverages this controlled space for top profits.

Key Considerations for Selecting Polyhouse Crops

Choosing crops isn’t random. Think about:

A. Market Demand & Profit: What sells well locally or for export? (e.g., Cherry tomatoes, colored capsicums, Gerbera flowers). High-value crops justify the setup cost.

B. Environmental Needs: Match the crop to your polyhouse tech. Tomatoes need warmth and lots of light; orchids need high humidity.

C. Growth Cycle: Fast crops (like lettuce – ready in 30 days) give quick returns. Slower ones (like melons) need planning. Stagger planting for constant supply.

D. Polyhouse Type: Simple low-cost polyhouses suit leafy greens or cucumbers. High-tech (with cooling, sensors) is needed for roses or strawberries.

E. Pest Management: Prevention is vital! Use clean soil/netting and monitor closely – problems spread fast inside.

F. Local Climate: Is your polyhouse for summer cooling? (Great for lettuce). Winter heating? (Essential for winter tomatoes). Or monsoon protection? (Saves cucumbers from rot).

Comprehensive Polyhouse Crops List

Here’s a list of proven winners, categorized:

A. Vegetables (The Money Makers):

Tomatoes (Cherry, Beefsteak): #1 polyhouse crop globally. High yield, constant demand.

Bell Peppers (Capsicum): Especially colored (red, yellow) – fetch premium prices.

Cucumbers (European, Beit Alpha): Grow fast, love warmth.

Leafy Greens: Lettuce (Romaine, Butterhead), Spinach, Kale. Fast-growing, low-light tolerant.

Beans (French Beans): High yield in vertical systems.

Eggplant (Brinjal): Does well with support and pest protection.

B. Flowers (High Profit Beauty):

Roses: Cut flowers command top prices year-round.

Gerbera: Large, colorful blooms – very popular.

Carnations & Chrysanthemums: Reliable, long vase life.

Orchids (Phalaenopsis): Need specific care but are high-value.

Lilies & Anthurium: Unique shapes, good for specialty markets.

C. Fruits (Special Treats):

Strawberries (Day-neutral): Grow vertically, produce almost year-round.

Melons (Cantaloupe, Honeydew): Trellised for quality; need good tech.

Dwarf Citrus Trees (Lemons, Oranges): Possible in large polyhouses/pots.

D. Herbs & Speciality:

Basil, Mint, Coriander, Parsley, Chives: High demand from restaurants/supermarkets.

Microgreens & Sprouts: Very fast, very high value per square foot.

Exotic Herbs (Stevia, Lemongrass): If your local market wants them.

Polyhouse Farming Crops: In-Depth Examples

A. Tomato Case Study:

Why Ideal? Needs warm roots, hates rain, high market demand. Yields can reach 40-50 kg/sq.m/year vs. 10-15 kg in fields.

Key Practices: Train vines vertically, prune suckers, use bumblebees for pollination, precise nutrient feed (often hydroponics).

B. Gerbera Case Study:

Why Ideal? Needs precise temps (18-25°C), high light. A single plant can produce 50-70 flowers/year for 2-3 years!

Key Practices: Use raised beds/coco coir, remove unwanted buds (“disbudding”), strict hygiene to prevent root diseases.

C. Year-Round Lettuce Case Study:

Why Ideal? Grows in just 4-6 weeks, constant demand, tolerates lower light than fruiting crops.

Key Practices: Perfect for hydroponics/NFT systems, plant new seeds every week (“succession planting”) for non-stop harvest.

Beyond the Basics: Advanced & Niche Crops

A. Hydroponic/Aeroponic Crops: Lettuce, herbs, and tomatoes excel with roots directly in nutrient-rich water/mist – boosting yields and saving water.

B. Grafted Vegetables: Tomato or cucumber plants grafted onto disease-resistant roots are common in polyhouses for extra vigor and longevity.

C. Seedling Production: Polyhouses are perfect nurseries for raising vegetable, flower, or tree seedlings before transplanting outdoors.

D. High-Value Medicinal Plants: Some herbs needing exact conditions (like specific light cycles) can be niche polyhouse crops.

Optimizing Your Polyhouse Crop Selection

Rotate Crops: Don’t grow tomatoes in the same spot every year – rotate with leafy greens or beans to prevent soil diseases.

Match to Your Setup: Be realistic. A simple polyhouse won’t grow orchids well. Start with tomatoes, cucumbers, or greens.

Start Small: Beginners should focus on 1-2 easy, high-demand crops (e.g., lettuce + cucumbers). Scale up as you learn.

Localize! This is crucial. The “best” crop in Holland might fail in India. Talk to local experts, research your market, and test!

Conclusion: The Future of Polyhouse Crops

Polyhouse farming unlocks incredible diversity – from everyday tomatoes to exotic flowers – all grown efficiently year-round. Technology (like automated climate control and hydroponics) keeps expanding the possibilities. As we face climate change and water scarcity, polyhouse crops offer a sustainable path to growing more food with fewer resources, making them vital for the future of farming. Choose wisely, start smart, and your polyhouse can be a powerhouse of productivity!