What are Thistles

Thistles grow as a rosette of leaves close to the ground from which grow tall stems carrying the flowers. Flowers are mainly pink-purple although there are some yellow flowering thistles.

Thistles leaves are pale green covered with hairs and spines. Thistles at the seedling or rosette stage are easily controlled by non-selective herbicides such as Yates Zero Super Concentrate Weedkiller. During the winter months, thistles are dormant and herbicides are relatively ineffective (as herbicides rely on the weed being in active growth).

Spring to autumn are the best times to control thistle. Spraying at early stages of growth is the most effective. Control of thistle at the flowering stage or later has much reduced success.


How to protect your plants

For control of individual plants in garden beds, use manual methods such as hoeing, making sure to remove at least the top third of the tap root.


Recommended products

More articles


A perennial herb with a very long tap root; mid-green and deeply divided leaves; and yellow daisy-like flowers.

Onion Weed

A bulb plant with strappy leaved and white star shaped flowers. Bulblets are esaily dislodged from the main plant, further spreading the weed.


A perennial weed which has leaves with three leaflets, and creeping stems that set roots wherever they touch the ground.


A tough, broad-leafed perennial grass with deep longitudinal veins and caterpillar-like black, sticky seed heads.