Yes, you can grow dwarf avocado plants in an outdoor plant box! Dwarf avocado varieties, such as 'Wurtz' or 'Little Cado,' are ideal for container gardening due to their compact size. Here’s how to ensure success:

1. Choose the Right Plant Box: Opt for a large, sturdy container (at least 24 inches deep) with proper drainage to accommodate the avocado’s root system.

2. Soil Requirements: Use well-draining, nutrient-rich soil with a slightly acidic pH (6.0–6.5). Adding compost can boost growth.

3. Sunlight: Place the plant box in a sunny spot where the avocado can receive 6–8 hours of direct sunlight daily.

4. Watering: Keep the soil consistently moist but not waterlogged. Avocados dislike soggy roots.

5. Fertilization: Feed with a balanced, slow-release fertilizer every 2–3 months to support healthy growth.

6. Winter Care: If temperatures drop below 50°F (10°C), move the plant box indoors or provide frost protection.

With proper care, your dwarf avocado plant can thrive in an outdoor plant box, yielding delicious fruit in a few years. Happy gardening!