What To Grow In A Louisiana Greenhouse: Best Plant Picks

Growing in a greenhouse in Louisiana is both opportunity and challenge. The state offers long growing seasons, warm winters in the south, and intense summer heat and humidity statewide. A greenhouse gives control over temperature, pests, and season extension, but success depends on choosing the right crops, the right structure, and the right cultural practices. This article walks through the best plant picks for Louisiana greenhouses, explains why they work, and provides practical, actionable guidance on planting schedules, varieties, and day-to-day care.

Louisiana climate factors that matter for greenhouse growing

Louisiana is hot and humid for much of the year. Summers can exceed 95 F and humidity often stays above 70 percent. Winters are mild in the southern parishes and cooler inland and north, with USDA zones ranging roughly from 8a to 10a in coastal areas and 7a to 8b farther north. Coastal flooding, heavy rains, and hurricanes are also considerations.
Humidity, heat, and pest pressure change greenhouse management: high humidity increases fungal disease risk; high temperatures require shading and ventilation; and robust pest populations mean good integrated pest management (IPM) is essential. Soil-borne diseases and drainage are also important because heavy rains and standing water are common outdoors and can affect inside operations if not managed.

Choosing the right greenhouse type and siting for Louisiana

The structure and site determine what you can grow and how easily you’ll manage climate.

• Place the greenhouse on slightly elevated, well-drained ground to reduce flooding risk and improve air movement.
• For materials, consider polycarbonate glazing or high-quality polyethylene film. Polycarbonate gives better insulation and durability; double-wall polycarbonate helps reduce heat spikes and provides diffused light.
• Include roll-up sides, ridge vents, and exhaust fans for summer ventilation. Shade cloth (30 to 50 percent) hung externally or mounted on the roof helps control solar heat gain in mid-summer.
• Consider a hoop house or shadehouse for mostly shade-tolerant crops and tunnel-style greenhouses for heavier production.
• If hurricanes are possible in your location, use anchoring systems and removable coverings or plan for a reinforced structure.

What to grow: vegetables that thrive in Louisiana greenhouses

A greenhouse allows you to grow crops out of season and protect high-value plants from storm damage and pests. Here are top vegetable picks and specific tips for each.

Tomatoes and peppers

Tomatoes and peppers are classic greenhouse crops that do well with heat management and vertical support.

• Choose heat-tolerant, disease-resistant varieties. For tomatoes consider ‘Solar Fire’, ‘Heatmaster’, or determinate types like ‘Bella Rosa’ for greenhouse production. For peppers, look at ‘California Wonder’ and hot pepper varieties that tolerate heat such as ‘Jalapeno’ or ‘Thai Hot’.
• Maintain day temperatures 75 to 85 F and night temperatures above 60 F for fruit set. In peak summer, aim to keep max greenhouse temperatures below 90 F during the day with ventilation and shading.
• Use trellising or string support and space 18 to 24 inches apart for determinate, 24 to 36 inches for indeterminate varieties.
• Fertilize with a balanced soluble fertilizer (e.g., 14-14-14) early, then switch to a potassium-heavy bloom feed once flowering begins.

Cucumbers, squash, and melons

Cucumbers and vining squash do well if humidity is controlled to reduce powdery mildew and downy mildew.

• Train cucumbers on trellises to save space and improve airflow; spacing can be 12 to 18 inches per plant.
• Choose powdery-mildew-tolerant varieties and remove lower leaves to improve air circulation.
• Melons need warm days and dry foliage; use drip irrigation under the canopy to keep leaves dry.

Leafy greens and salad crops (cool season)

Greenhouses allow you to grow salad greens in cooler months (fall through spring), avoiding summer bolting.

• Grow lettuce, arugula, spinach (cold-hardy varieties), and mizuna in fall through spring. Maintain day temps around 60 to 68 F for crisp leaf quality; night temps around 45 to 55 F.
• Use shade during spring transitional periods to prevent bolting as temperatures begin to rise.
• These crops do best in raised benches or containers with light, well-draining mixes and regular fertilization for continuous harvests.

Herbs, microgreens, and high-value short-cycle crops

Herbs and microgreens are excellent greenhouse choices because they are high-value, quick turnover, and tolerant of benches and containers.

• Basil, cilantro, parsley, chives, and Thai basil perform well. Basil thrives in heat but dislikes cold; keep temps 70 to 85 F.
• Microgreens can be grown year-round, harvested in 7 to 21 days, and provide fast revenue or kitchen use.
• Use seed-starting mixes and maintain consistent moisture; microgreens benefit from good light (LEDs or supplemental lighting in winter).

Tropical and subtropical fruit, ornamentals, and specialty crops

Louisiana’s climate makes it possible to grow many tropicals in a greenhouse with humidity and temperature control.

• Citrus seedlings, passionfruit, figs, dwarf banana, and papaya can be grown in containers inside a greenhouse, particularly in cooler northern parishes. Ensure pollination either with bumblebees or hand pollination where needed.
• Orchids, gingers, and anthuriums appreciate the humidity and shaded environment of a greenhouse. Provide shade cloth and bark-based media for orchids, plus good airflow to prevent fungal disease.
• Succulents and cacti need bright light and lower humidity–grow them on a separate bench with excellent drainage and open ventilation to keep fungal problems at bay.

Pest and disease management strategies for humid Louisiana

High humidity and mild winters allow many pests and pathogens to persist year-round. Effective IPM combines prevention, monitoring, and control.

• Sanitation: Remove plant debris, sanitize benches, and use clean potting mix to limit fungal spores and pests.
• Monitoring: Use sticky traps for whiteflies and fungus gnats; scout weekly for aphids, thrips, and mites.
• Cultural controls: Reduce humidity with ventilation, run fans for air circulation, and avoid overhead irrigation when possible.
• Biological control: Introduce beneficials such as Encarsia formosa for whiteflies, Steinernema feltiae for fungus gnat larvae, and predatory mites for spider mites when appropriate.
• Chemical controls: Use targeted products labeled for greenhouse use only when needed and rotate modes of action to reduce resistance. Apply fungicides preventatively for downy and powdery mildew in vulnerable crops.
• Integrated crop spacing and pruning increase airflow and reduce disease incidence.

Soil, substrates, irrigation, and fertility

Greenhouse crops often do best in containers, raised beds, or bench systems rather than in-ground, especially in flood-prone areas.

• Use high-quality soilless mixes with peat or coconut coir, perlite, and compost. Good drainage is essential.
• Drip irrigation and two-stage irrigation (slow soak then brief flush) reduce disease risk compared to overhead watering.
• Fertility: Use controlled-release granular fertilizers at potting or a soluble fertilizer program through fertigation. Monitor EC and pH (ideal pH 5.8 to 6.5 for most vegetables).
• For heavy feeders like tomatoes and cucurbits, increase potassium for fruiting and provide regular calcium to minimize blossom end rot (foliar calcium sprays or consistent soil moisture).

Planting calendar and rotation for Louisiana greenhouses

A greenhouse lets you run multiple seasons. Example schedules for a central Louisiana location:

• January to March: Start tomatoes, peppers, eggplants, herbs; grow cool-weather lettuce and spinach in shaded bays.
• April to June: Transition to heat crops like cucumbers and melons with shade cloth installed in May; manage ventilation and shading.
• July to September: Emphasize shade, ventilation, and heat-tolerant varieties; focus on microgreens, herbs, and tropicals that handle humidity.
• October to December: Prime season for leafy greens, brassicas, and cool-season herbs; dark and cooler months may require supplemental lighting for transplants.

Rotate crop families across benches or containers to reduce soil-borne disease buildup and manage nutrient needs.

Best plant picks by season and purpose

• Spring/early summer: Tomatoes (indeterminate greenhouse varieties), peppers, cucumbers, basil, eggplant.
• Summer: Heat-tolerant peppers, okra (in containers), microgreens in shaded benches, tropical ornamentals.
• Fall/winter: Lettuce, spinach, arugula, pak choi, cilantro, parsley, and brassicas (broccoli, kale) with cold protection as needed.
• Year-round options: Herbs (basil in warm months, parsley and chives year-round), microgreens, ornamental orchids (with humidity control).

Concrete plant variety recommendations and spacing (practical list)

• Tomatoes: ‘Solar Fire’ or ‘Heatmaster’; indeterminate spacing 24 to 36 inches.
• Peppers: ‘California Wonder’ (sweet), ‘Jalapeno’, ‘Cayenne’; spacing 12 to 18 inches.
• Cucumbers: ‘Marketmore 76’ (disease resistant); trellised spacing 12 inches.
• Lettuce: ‘Salad Bowl’, ‘Buttercrunch’; spacing 6 to 10 inches in staggered plantings.
• Basil: ‘Genovese’ for culinary, ‘Thai’ for heat tolerance; plant 8 to 12 inches apart.
• Microgreens: Mixes (radish, mustard, sunflower) harvested at 7 to 14 days.
• Citrus (container): ‘Meyer Lemon’ or dwarf mandarins; container 15 gallons or larger with regular feeding.
• Orchids: Phalaenopsis for beginners; bark mix, bright shade, and consistent humidity.

Practical takeaways and greenhouse checklist for Louisiana growers

• Prioritize ventilation, shade, and elevated siting to deal with heat, humidity, and flooding risk.
• Use polycarbonate glazing and roll-up sides for flexible climate control; shade cloth is a summer must.
• Focus on heat- and humidity-tolerant varieties for summer; use the greenhouse to grow cool-season greens in fall and winter.
• Install drip irrigation and benches; avoid overhead watering where possible.
• Implement IPM: sanitation, sticky traps, biological controls, and targeted chemical use only when necessary.
• Rotate crops and sanitize pots and benches between cycles to minimize disease carryover.
• Keep a seasonal calendar and seed-starting schedule: start warm-season transplants in late winter in central and northern parishes; in southern parishes you can start earlier.
• Maintain records of varieties, planting dates, and issues to refine your greenhouse plan year to year.

Growing in a Louisiana greenhouse can transform what you can produce and when you can produce it. With the right structure, crop selection, and cultural practices focused on heat, humidity, and pest control, you can harvest high-value vegetables, herbs, ornamentals, and specialty fruit nearly year-round. Plan for ventilation and shading, choose tolerant varieties, and adopt a vigilant IPM approach to maximize success.