Welcome to the Garden Ninja Gardening Forum! If you have a gardening question that you can't find answers to then ask below to seek help from the Garden Ninja army! Please make your garden questions as specific and detailed as possible so the community can provide comprehensive answers in the online forum below.

Welcome to the ultimate beginner gardening and garden design forum! Where no gardening question is too silly or obvious. This online gardening forum is run by Lee Burkhill, the Garden Ninja from BBC 1's Garden Rescue and a trusted group of experienced gardeners.

Whether you are a beginner or an expert gardener, it's a safe place to ask garden-related questions for garden design or planting. If you have a problem in your garden or need help, this is the Garden Forum for you!

Posting Rules: This space is open for all garden-related questions. Please be polite, courteous and respectful. If you wouldn't say it to your mum's face, then don't post it here. Please don't promote, sell, link spam or advertise here. Please don't ask for 'cheeky' full Garden redesigns here. They will be deleted.

If you need a garden design service, please use this page to book a design consultation. I will block anyone who breaks these rules or is discourteous to the Garden Ninja Community.

Join the forum below with your gardening questions!

Ask a Gardening QuestionGardening Questions & Answers: How to garden questionsEucalyptus Gunnii

Please or Register to create posts and topics.

Eucalyptus Gunnii

#1 · 17th March 2024, 6:25 pm

Advice please! I have just ordered two eucalyptus gunnii trees and plan to keep them small/ the size that they will be when they arrive (process 7/8 ft and I have a small garden). However, I have just read that their roots are invasive. Would it be okay to plant them in the ground if they are pruned to be kept small or would you plant in a root barrier??

#2 · 18th March 2024, 9:52 am

Quote from Lee Garden Ninja on 18th March 2024, 9:52 am
Hi @alisa_ede
Thanks for your comment about Eucalyptus trees in garden design and planning. Eucalyptus can be one of the most vigorous tree genera to plant in a garden, but as with all tree species, it's about picking the right cultivar or species for your needs and garden size.
Eucalyptus gunnii is one of the smallest and most well-behaved genera.
Taller species of Eucalyptus will have far stronger roots. These roots can cause a problem in smaller gardens, but gunnii should be fine, given its slow growth. I've seen them grown in large containers, but trees are nearly always better grown in the ground where they can seek out their own moisture and nutrients. Any tree grown in a container or pot will need regular watering and feeding as the plant or tree is entirely dependent on you, the gardener, for its survival, which puts a lot of pressure on a time-poor gardener!
Does Eucalyptus stop other plants from growing around them?
One thing to remember is that Eucaptupus can prevent plants from growing underneath them, a bit like Walnuts. It's a survival mechanism called allelopathy.
Eucalyptus trees are known for their allelopathic properties, which means they release chemicals into the soil that inhibit the growth of other plants nearby. These chemicals, such as allelochemicals, can hinder the germination, growth, or establishment of certain plant species. While eucalyptus trees can create challenging conditions for other plants to grow in their vicinity, they do not necessarily poison the soil in the traditional sense. Instead, they alter the soil chemistry in a way that makes it less favourable for competing vegetation. Additionally, eucalyptus trees are well-adapted to thrive in their native environments, where they may dominate the landscape due to their allelopathic effects.
When to coppice or prune eucalyptus?
All Eucalyptus will require pruning every couple of years to curtail their growth and keep a neat habit even Eucalyptus gunnii.
Coppicing eucalyptus trees should be done during the tree's dormant season, which typically occurs in late winter or early spring, depending on your specific climate and the eucalyptus species. It's best to avoid coppicing during periods of active growth to minimize stress on the tree.
Aim to coppice when the tree is dormant and before the onset of new growth in the spring. This timing allows the tree to recover and produce new shoots efficiently. Additionally, consider the age and health of the tree when deciding on the timing of coppicing, as younger trees may respond more vigorously to the process compared to older, established ones.
I hope that helps!
Lee Garden Ninja

Hi @alisa_ede

Thanks for your comment about Eucalyptus trees in garden design and planning. Eucalyptus can be one of the most vigorous tree genera to plant in a garden, but as with all tree species, it's about picking the right cultivar or species for your needs and garden size.

Eucalyptus gunnii is one of the smallest and most well-behaved genera.

Taller species of Eucalyptus will have far stronger roots. These roots can cause a problem in smaller gardens, but gunnii should be fine, given its slow growth. I've seen them grown in large containers, but trees are nearly always better grown in the ground where they can seek out their own moisture and nutrients. Any tree grown in a container or pot will need regular watering and feeding as the plant or tree is entirely dependent on you, the gardener, for its survival, which puts a lot of pressure on a time-poor gardener!

Does Eucalyptus stop other plants from growing around them?

One thing to remember is that Eucaptupus can prevent plants from growing underneath them, a bit like Walnuts. It's a survival mechanism called allelopathy.

Eucalyptus trees are known for their allelopathic properties, which means they release chemicals into the soil that inhibit the growth of other plants nearby. These chemicals, such as allelochemicals, can hinder the germination, growth, or establishment of certain plant species. While eucalyptus trees can create challenging conditions for other plants to grow in their vicinity, they do not necessarily poison the soil in the traditional sense. Instead, they alter the soil chemistry in a way that makes it less favourable for competing vegetation. Additionally, eucalyptus trees are well-adapted to thrive in their native environments, where they may dominate the landscape due to their allelopathic effects.

When to coppice or prune eucalyptus?

All Eucalyptus will require pruning every couple of years to curtail their growth and keep a neat habit even Eucalyptus gunnii.

Coppicing eucalyptus trees should be done during the tree's dormant season, which typically occurs in late winter or early spring, depending on your specific climate and the eucalyptus species. It's best to avoid coppicing during periods of active growth to minimize stress on the tree.

Aim to coppice when the tree is dormant and before the onset of new growth in the spring. This timing allows the tree to recover and produce new shoots efficiently. Additionally, consider the age and health of the tree when deciding on the timing of coppicing, as younger trees may respond more vigorously to the process compared to older, established ones.

I hope that helps!

Lee Garden Ninja