Biodegradable vs Plastic Plant Guards: What’s Best for NZ Planting Projects?

When planning a planting project in New Zealand, one important decision is whether to use biodegradable or plastic plant guards.

Both options provide protection from browsing pests, wind and spray drift. However, they differ significantly in environmental impact, long-term site management and practical use.

Understanding these differences helps you choose the right solution for your project.

Why Plant Guards Are Used in NZ

Plant guards are commonly used to:

• Protect young plants from hares, rabbits and other browsing pests

• Reduce wind stress on exposed sites

• Protect against spray drift during weed control

• Improve early establishment success

The key difference lies in what happens after the plant is established.

Plastic Plant Guards

Plastic guards have been widely used for many years. In exposed alpine or high-country environments, plastic guards can offer advantages. Their durability allows them to withstand prolonged snow cover, heavy frost and extreme wind without softening or degrading. For projects in harsh conditions where long-term structural strength is required, plastic guards may provide more reliable performance.

However, the trade-off is long-term site management. Plastic guards must be removed once plants are established. In large-scale or remote projects, retrieval can be labour-intensive and costly. If not collected, plastic guards can remain in the landscape for years, becoming brittle and breaking into fragments.

Advantages

• Durable

• Can last multiple seasons

• Strong in high-wind environments

Disadvantages

• Must be removed manually

• Often left behind, creating long-term plastic waste

• Labour costs for collection and disposal

• Risk of becoming brittle and breaking into fragments

• Ongoing environmental impact

For large-scale planting projects, the cost of retrieving plastic guards can be significant. In many cases, they are not collected, contributing to farm and restoration site plastic waste.

Biodegradable Plant Guards

Biodegradable guards are designed to last long enough for plant establishment, then naturally break down.

Quality biodegradable guards typically:

• Last approximately 12–18 months

• Maintain structure during early growth

• Decompose without leaving plastic fragments

Advantages

• No removal required

• Reduced long-term site waste

• Lower labour costs after establishment

• Environmentally responsible option

• Increasingly preferred for council and farm projects

Considerations

• Must be properly manufactured to maintain strength during their intended lifespan

• Should match site conditions and browsing pressure

Well-designed biodegradable guards provide practical protection without creating future clean-up work.

Environmental Impact

In New Zealand, reducing on-farm and restoration plastic is becoming a priority.

Plastic plant guards can remain in the environment for many years. Even when partially removed, fragments may remain in soil or waterways.

Biodegradable guards align better with:

• Farm sustainability goals

• Council environmental standards

• Regenerative land management practices

• Long-term restoration planning

For many landowners, avoiding plastic accumulation is now a key decision factor.

Installation Efficiency

For large planting projects, installation speed matters.

Modern biodegradable guards, such as pre-glued EnviroGuards, are supplied ready to install — no folding required onsite. When paired with biodegradable weed mats and bamboo stakes, they create a fully integrated protection system.

This can improve planting efficiency and reduce handling time compared with some plastic systems.

Cost Comparison

Upfront costs between plastic and biodegradable guards can vary depending on supplier and scale.

However, total project cost should consider:

• Installation time

• Guard removal labour

• Disposal costs

• Long-term environmental impact

• Replanting due to poor protection

In many large-scale NZ planting projects, biodegradable guards provide stronger overall value when labour and clean-up are factored in.

When Plastic May Still Be Used

Plastic guards may still be considered when:

• Extremely long-term protection is required

• Reuse is planned and guaranteed

• Environmental impact is not a primary concern

However, trends across New Zealand show increasing preference for biodegradable alternatives.

Choosing the Right Option for Your Project

The best plant guard for your project depends on:

• Scale of planting

• Browsing pressure

• Exposure

• Environmental priorities

• Long-term maintenance plans

For farm blocks, forestry planting and environmentally focused projects, biodegradable plant guards are becoming the practical standard.

Final Thoughts

Plant protection is essential in the first year of establishment. The decision between plastic and biodegradable guards affects not only survival rates but also long-term site management.

For many New Zealand planting projects, biodegradable guards offer the right balance between durability, practicality and environmental responsibility.

If you are planning a large-scale planting programme, it’s worth considering both the short-term protection and the long-term impact of your choice.