Until about a month ago, I didnt have a single Melaleuca in my garden. I couldnt really give you a reason as to why this was the case, and I gave in to the form and foliage of the following varieties in rapid succession:

M. Thymifolia
M. Bracteatea (Revolution Gold)
M. 'Claret Tops'
M. Armillaris (Bracelet Honey-Myrtle)

Having planted these some 4-6 metres from my house in the belief that a native shrub wouldnt pose a problem, you can imagine my joy when I read John Mason's list ('Trees and Shrubs for Small Gardens) of plants he feels arent suited to small gardens due to invasive root systems. As M. Armillaris can reach 4-6M in height, I will move it as a precaution, but the remainder are significantly smaller, if the cards are to be believed. I am very keen to hear from anyone who has mature Melaleuca, particularly those who have had problems in this area.

It would seem that they aren't terribly popular in Florida:

'Melaleuca quinquenervia: An Australian native escaped in early 1900s into Florida wetlands and is now dominant tree for miles on end'

None of these are large trees/shrubs so I wouldn't have thought that roots would really be a problem. A lot seems to depend on the type of soil you have. The general rule (as far as I can understand) is to plant trees and shrubs their mature height away from any structures. In the case of thymifolia and claret tops, this will be 1+ metres while for the Revolution Gold it will be 4+ metres. However, the distance will be strongly influenced by the type of soil. If you have reactive clay soil which expands and contracts considerably in the wet and the dry, you may think about planting them 2x or 3x their mature height away from any structures. This is just a general guide.

Ian

Here in California with our Mediterranean rainfall pattern and dry summers, they have not tended to spread into the wild or become problems, even in summer irrigated gardens. We certainly don't grow the vast amount of species that exist in Australia, but they are very popular trees and shrubs in much of California, and are almost ubiquitous in shopping malls of Southern California, where M. quinquenervia in particular is much used. Several species of Melaleuca were also used to help stabilize sand dunes when San Francisco's Golden Gate Park was first built at the turn of the last century. They are generally considered relatively trouble free plants here in California, but most aren't hardy enough to be used away from the coast. Among their attractive qualitites here are nearly year round or winter bloom, and their ability to survive and thrive on zero supplemental irrigation once established. However, several species are extremely intolerant of drying out as container plants, and require careful nurturing once planted until they root in. I have seen species such as M. linariifolia quickly die if not watered daily as container plants, and they do not revive if allowed to dry out. Same thing with Leptospermum scoparium here. We tend to think of them as all being very drought tolerant under our conditions, so it is rather surprising to know that many grow in seasonally inundated areas in habitat.

You could try "cut and paint" with neat glyphosate.

I have used this on suckers from Cheese trees, Glochidion ferdinandi, and it does not seem to harm the large tree, just knock back the suckers.

Maybe you should consider just removing the whole thing and planting something that does not bother you so much.

All the best.

Popi