Plant Substitution Dangers

The Dangers of Replacing Plants on Landscape Projects

Plants are dangerous to substitute, particularly in commercial projects where hundreds of thousands of dollars are at stake.

New performance based plant breeding is taking off. Landscape architects are specifying plants and the public are asking for plants that can cope with disease, waterlogging and drought, or grow in tight spaces, or do not burn easily in fires, or are less likely to cause allergies. As an example there are now Lomandra that are highly resistant to Phytophthora, can grow in wet or dry soil, such as Shara™ Lomandra fluviatilis ‘ABU7’ PBR, Evergreen Baby™ Lomandra labill ‘LM600’ PBR, and Tropic Cascade™ Lomandra hystrix ‘LHWP’ PBR.

Once upon a time it was all about asthetics, and the nursery could easily offer something else that looked similar if the did not have them, but in the modern world looks are shallow, and performance to adverse conditions is often king.

Beware the Hidden Dangers of Plant Substitution

The right plant choice can mean the difference between thriving greenery and a costly catastrophe. Missteps in plant selection can lead to costly replacements, unhappy clients, and even legal action.

Todd Layt, the founder and head breeder at Ozbreed recently said, “Be careful. I have seen many nurseries and landscapers having to dig deep into their pockets, to replace failed plants, or simply the wrong plants. It’s surprising how often they get caught now that plants are bred for performance rather than looks.”

He also explained ways they have reduced substitution. “We used to have nurseries substituting our plants a lot, due mainly to the fact that we had a select group of growers who could grow them. Now we have our Ozbreed Easy Access system where almost all nursery growers can buy the young plants, this problem is easing a little.”

As a landscaper or nursery supplier, you know how important it is to use the right plants for each project. Not only do you want to provide your clients with beautiful and healthy greenery, but you also want to avoid any potential litigation and loss of reputation.

In some cases, plant substitution may seem like a quick and easy solution. But in reality, it can cause major problems down the line. Plants that are not suitable for the specific environment or location may not thrive or may even die en masse. Substituting can lead to serious consequences, potentially for both for the landscape contractor and for the supplying nursery.

Case in Point

Take, for instance, the inappropriate substitution of Shara™ Lomandra fluviatilis ‘ABU7’ PBR in rain gardens and bioretention swales. Shara™ Lomandra is specifically bred and naturally suited for such conditions, given its remarkable tolerance to wet feet. When other plants are substituted, like common Lomandra confertifolia, the consequences can be disastrous.

An unfortunate example of this is a project in Queensland. Despite the explicit specification for Shara™ Lomandra, Lomandra confertifolia was used instead, resulting in the death of most of the 30,000 plants and legal action against those responsible for the substitution.

Another instance where plant substitution has caused unnecessary problems has been the replacement of Luscious® Tristaniopsis laurina ‘DOW10’ PBR, a beautiful, moderate-sized tree, with a common, larger variant which can grow up to 50% larger. This can lead to the encroachment of branches where they are unwanted and can overwhelm smaller spaces.

Hold Point

One of the main reasons plants get substituted is because landscape construction crews leave it too late to order plants, and have a laissez-faire attitude toward their plant schedules. They don’t understand the subtle differences in plant performance once they leave the project in the hands of the maintenance crew.

Specifiers can insist on a hold point that prevents landscapers stepping foot on-site until plants have been organised through a reputable nursery.

Final Thoughts

When it comes to landscaping projects, there is no room for shortcuts or substitutions. Nor is there any reason to on most projects that have a good lead time; as long as you give your preferred wholesaler or grower a plant schedule with several months’ lead time, there should be much fewer substitutions in your projects.