Greenhouse Sizing Calculator
Find the perfect greenhouse size for your space, budget, and growing goals. Our calculator considers your available area, plant requirements, and future expansion plans.
Enter your requirements and click calculate to see a recommended greenhouse size.
Enter your requirements and click calculate to see a recommended greenhouse size.
Your Requirements
Recommendations
Enter your requirements and click calculate to see our recommendations
Small Greenhouses
6×8 to 8×10 feet
Best for: Beginners, herbs, seed starting
Medium Greenhouses
8×12 to 12×16 feet
Best for: Family gardens, year-round growing
Large Greenhouses
16×20+ feet
Best for: Commercial production, research
Greenhouse Sizing Guidelines
Hobby Growing (6x8 to 8x10)
- • 15-25 plants: Tomatoes, peppers, herbs
- • Best for: Beginners, small families
- • Space per plant: 2-3 sq ft
- • Annual value: $300-800 produce
- • Heating cost: $150-400/year
Family Production (8x12 to 10x16)
- • 30-50 plants: Diverse crop mix
- • Best for: Serious gardeners
- • Includes: Workspace, storage area
- • Annual value: $800-2,000 produce
- • Heating cost: $300-800/year
Market Growing (12x20+)
- • 75+ plants: Commercial potential
- • Best for: Market sales, CSA
- • Features: Automation, efficiency
- • Annual value: $2,000-8,000+
- • ROI potential: 1-3 year payback
Space Requirements by Crop Type
| Crop Type | Space per Plant | Plants per 100 sq ft | Annual Harvests |
|---|---|---|---|
| Tomatoes (indeterminate) | 4 sq ft | 25 plants | 1-2 crops |
| Peppers & Eggplant | 2-3 sq ft | 35-50 plants | 1-2 crops |
| Lettuce & Leafy Greens | 0.5-1 sq ft | 100-200 plants | 6-12 crops |
| Herbs (basil, cilantro) | 0.5-1 sq ft | 100-200 plants | 4-8 crops |
| Cucumbers (vining) | 3-4 sq ft | 25-35 plants | 2-3 crops |
🏗️ Space Planning Tips
- • Walkways: Reserve 20-30% for pathways
- • Work area: Include 10-20 sq ft for potting
- • Storage: Plan space for tools and supplies
- • Vertical space: Consider hanging systems
- • Future expansion: Buy 20% larger than needed
- • Door swing: Account for door operation
📏 Standard Greenhouse Sizes
- • 6x8 (48 sq ft): Starter size, 15-20 plants
- • 8x8 (64 sq ft): Popular hobby size
- • 8x10 (80 sq ft): Good for beginners
- • 8x12 (96 sq ft): Most popular size
- • 10x12 (120 sq ft): Family production
- • 12x16 (192 sq ft): Serious growing
⚠️ Common Sizing Mistakes
- • Building too small: 95% wish they built bigger
- • Ignoring walkways: Need 24" minimum paths
- • No work space: Include potting/storage area
- • Wrong proportions: Consider length vs width
- • Site constraints: Measure available space carefully
- • Door location: Plan entrance and access
- • Future needs: Consider growing interest
- • Budget mismatch: Size affects total cost
Site Requirements & Clearances
Minimum Clearances
- • Property lines: Check local setback requirements
- • House/structures: 3+ feet minimum
- • Trees: Consider mature canopy size
- • Utilities: Call 811 before digging
- • Access: Allow room for delivery/maintenance
Site Preparation Space
- • Excavation: Add 2-3 feet on all sides
- • Material staging: Room for kit delivery
- • Equipment access: Consider concrete trucks
- • Drainage: Grade away from greenhouse
- • Future expansion: Leave room to grow