General gardening topics

How and when to prune Phormiums (New Zealand Flax)

Our site is reader supported, this means we may earn a small commission from Amazon and other affiliates when you buy through links on our site.

If you have a New Zealand flax evergreen shrub also known as a phormium, you can add a great deal of interest to your border garden or landscape and they make excellent centrepieces some varieties can even be grown in containers. As an evergreen shrub it provides you with years of foliage and blooms with very minimal maintenance once the plant is established.

One aspect of that minimal maintenance is pruning the New Zealand flax plant that only really needs doing to remove spent flowers and any leaves damaged by the winter.

When to prune your New Zealand flax

The best time to prune your New Zealand flax (Phorium) is going to be in the Autumn. You can prepare your plant for winter by getting rid of the flower stalks and any brown leaves that have been damaged. This won’t hurt the plant but it will go a long way toward encouraging new growth especially come springtime.

Even though the plant is technically evergreen throughout the winter if you have a very harsh UK climate where you live the leaves might be damaged by intense cold and if they turn brown you will have to remove them when it happens in the spring.

How to prune your New Zealand flax

The New England Flax is a robust plant that’s well-regarded for its large, spiky foliage but as it grows you need to maintain its shape and size with pruning. The process is fairly simple. The leaves are quite tough and firm so you will need a pair of gloves and a pair of strong, sharp gardening shears. Once you find the leaves that need to be removed because of damage or overgrowth, follow that leaf all the way down to the base of the plant and cut it off at the base.

Just the same as with any plant, always make sure that you regularly sanitize the tools you are using in between each use. This will prevent the spread of any disease from one plant in your garden to another. And again, the sharper the tool you are using, the more effective this process will be. 

This is a fairly simple process that, done regularly, will help keep new growth appearing every spring and improve the overall appearance of your plants.

You can also consider dividing phormiums to make new plants or to help reduce there size. You should also put a thick layer of mulch around the base over winter to protect the roots from long periods of frost which has been known to kill phormiums.

Welcome to my site, my name is John and I have been lucky enough to work in horticultural nurseries for over 15 years in the UK. As the founder and editor as well as researcher, I have a City & Guilds Horticultural Qualifications which I proudly display on our About us page. I now work full time on this website where I review the very best gardening products and tools and write reliable gardening guides. Behind this site is an actual real person who has worked and has experience with the types of products we review as well as years of knowledge on the topics we cover from actual experience. You can reach out to me at

Write A Comment