I’d never really taken much notice of thistles until I was traipsing through some of Tasmania’s pastoral areas. Then their flowers seemed to bob in the breeze creating as much attention for themselves as possible. Their artichoke shaped head covered with a punk rocking blaze of pink follicles are beautiful – but only when contained.

Scottish Thistles Are a Noxious Weed

The moment they escape their boundaries – and that’s not a difficult feat for a successful self-seeder – they can grow with amazing rapidity. The seed is either dispersed by the wind or scattered via small birds who view the seed as a delicacy.

But Scottish thistles, or cotton thistles as they are also commonly known, can be grown in your gardens and treated as a flowering biennial. They are part of the Asteraceae family and are found in the Cirsium genus, which is by no means a small variety.

It’s the same genus that sports Arizona, Japanese and Mexican thistles which are all fairly similar to look at but accommodate various leaf and flower shapes.

After seeing them growing profusely in Tasmania, I noticed a few creeping in our native wetlands while on a walk yesterday. They are extremely hardy and invasive and unless they are removed their attack on the native vegetation will continue.

If Scottish thistles are an unwanted weed in your garden the best management practice is to pull them up prior to flowering. Once they have flowered, the thistles next goal is to set seed and having done this will allow the seeds to be scattered so that it can reproduce.

However, if you like the look of the Scottish thistle it could be a welcome addition to a cottage garden but if you live near native vegetation you will need to remain vigilant against any escaping proteges.

Photo source: OliBac