What Do You Put On The Bottom Of A Raised Planter Box?

What Do You Put On the Bottom of a Raised Planter Box?

When building or purchasing a raised planter box, it’s crucial to consider what you will place at the bottom to ensure optimal plant growth and drainage. The choice of materials and methods depends on several factors, including the type of plants, box size, and available resources. This article delves into the various options for what to put on the bottom of a raised planter box, providing insights to help you make informed decisions.

1. Gravel or Stones

Gravel or small stones form an efficient drainage layer by creating air pockets and preventing waterlogging. They promote root aeration and prevent root rot, especially in areas with heavy rainfall or clay soil. Simply spread a 2-3 inch layer of gravel or stones over the bottom of the planter box.

Advantages:

• Excellent drainage
• Prevents root rot
• Creates air pockets for root aeration

Disadvantages:

• Can be costly for large planter boxes
• Requires regular cleaning to remove debris

2. Mesh or Screening

Landscape fabric, wire mesh, or hardware cloth placed at the bottom of the planter box prevents soil loss while allowing water to drain. This method is particularly beneficial for raised planters with multiple drainage holes or in areas with sandy soil.

Advantages:

• Prevents soil erosion
• Allows for drainage
• Inexpensive and readily available

Disadvantages:

• Can clog over time, reducing drainage
• Requires securing to prevent movement

3. Landscape Fabric

Landscape fabric is a non-woven material that allows water to pass through while blocking weeds. It protects the soil from erosion and prevents soil contamination from treated lumber or composite materials. Spread the fabric over the bottom of the planter box, ensuring it covers the entire base.

Advantages:

• Prevents weed growth
• Protects soil from erosion
• Durable and long-lasting

Disadvantages:

• Can be expensive for large planter boxes
• Requires securing to prevent movement

4. Geotextile Fabric

Similar to landscape fabric, geotextile fabric is slightly thicker and more durable. It provides excellent drainage and is resistant to punctures or tears. Geotextile fabric is a versatile option for raised planters in various settings and conditions.

Advantages:

• Superior drainage
• Puncture-resistant
• Long-lasting and durable

Disadvantages:

• More expensive than other options
• Requires securing to prevent movement

5. Wood Chips or Bark

Wood chips or bark can be used in raised planters, but they are not ideal for all plants. They decompose over time, adding nutrients to the soil and creating pockets for drainage. However, wood chips can retain moisture and may encourage pests, so they are best suited for moisture-tolerant plants.

Advantages:

• Adds nutrients to the soil
• Creates drainage pockets
• Inexpensive and readily available

Disadvantages:

• Can retain too much moisture
• Encourages pests
• Decomposes over time

Conclusion

Choosing the right material for the bottom of a raised planter box depends on your specific needs and preferences. Consider the type of plants you will be growing, the box size, and available resources. Gravel or stones provide excellent drainage and aeration, while mesh or screening helps prevent soil erosion. Landscape fabric or geotextile fabric offers weed control and soil protection, and wood chips or bark add nutrients to the soil. By selecting the appropriate material, you can create an optimal growing environment for your plants in your raised planter box.

Frequently Asked Questions

1. Can I put plastic at the bottom of a raised planter box?

Plastic is not recommended as it can prevent drainage and cause waterlogging.

2. How thick should the bottom layer be in a raised planter box?

The thickness of the bottom layer varies depending on the material used. For gravel or stones, aim for 2-3 inches. For mesh or screening, use a 1-inch layer.

3. Do I need to line the bottom of a raised planter box with wood?

Lining the bottom with wood is not necessary, but it can provide additional support and prevent soil loss.

4. Can I use old newspapers at the bottom of a raised planter box?

While old newspapers can be used to suppress weeds, they are not recommended as a permanent solution. They decompose quickly and can clog drainage holes.

5. How often should I replace the bottom layer in a raised planter box?

The frequency depends on the material used. Gravel or stones generally do not need replacing, while mesh or fabric may need to be cleaned or replaced every 2-3 years.