Most people just call it a weed, but to a Scot the thistle is the national emblem of his home country. And with good reason since in days gone by when the country was threatened by invaders from Norway as legend has it this sturdy plant saved the day. Allow one or two into your garden and you can enjoy their pretty flowers, but take very great care or you will be completely overrun by not just flowers but prickles too. Learn the full story in this article by Lee Royer which I found over on The Master Gardeners website.

Scotophiles everywhere adore their native thistle. Scottish children learn the story of the thistle before they outgrow thistle-decorated diapers. Here is the story: Long ago the Scots and Norse were at war. One dark night the Norsemen came ashore planning to surprise the sleeping Scottish forces, so removed their boots for a quieter assault. This might have been a fine plan, were it not for the prickly patch of Onopordum acanthium growing between the two armies.
Legend doesn’t tell us the exact words which woke the sleeping Scots, however if you grow Scottish Thistle, or if you’ve ever seen one, you can imagine what kind of cursing might result from a barefoot tread on a small one, much less running smack-dab into a full grown plant in the dead of night. Needless to say, the thistle was credited with saving the day and became the Scottish national flower and emblem.
Warning
As ancient Vikings would attest, thistles, even Scottish thistles, are not beloved by everyone. I don’t want to sugar coat this. I have seen them grown at such a respectable place as Longwood Gardens, Kennett Square, PA. and written about in such well-regarded references as Tracy DiSabato-Aust’s The Well-Tended Perennial Garden. However, in many places on several continents, including this one, they are sometimes considered noxious weeds. Don’t tell the Scots. So before I continue, here is a stern warning: If you want to grow them, you must promise, and keep your promise, to not let them become garden juvenile delinquents. Again, in plain language: control them or they will become horrible weeds.

Scottish Thistles are like large breed puppy dogs, Scottish Deerhounds my particular favorite. In the fall a small silver-gray rosette appears and you can’t imagine what problems could arise from such a cute little thing. The following spring it begins to grow and grow until soon it’s five to eight feet tall and four feet wide and covered with sharp stickers of various sizes. And then it blooms those famous globe-shaped flowers of dark pink and lavender. Much like a Scottish Deerhound grown into maturity, it is a stately, elegant life form, and a lovely shade of grey.

See more at The Master Gardeners