Three Favorite Biennials

The common foxglove, Digitalis purpurea

The gargantuan Scotch Thistle, Onopordum acanthium

Miss Willmott's Ghost, Eryngium giganteum

I don't mulch my garden until late June every year. It's not because I am behind schedule, it is because the annuals and biennials. The self-seeding annuals like poppies, nicotianas and Verbena bonariensis complete their life cycle in a single season. That is they germinate, flower, set seed and die before the first frost. Biennials germinate one year and flower the following year. So careful mulching is necessary to protect the seedlings in the springtime.

Digitalis purpurea, the common foxglove, grows in the dappled shade of woodlands in Europe, but it has been in grandmother's garden for generations. The Scotch thistle, Onopordum acanthium, feels much more exotic. I grow it in the pastel themed borders off the terrace. That garden is out of sight from the passerby and I like it to look best when we have guests for cocktails. In that light, the Scotch thistle's gray, edged-with-spikes, foliage seems to collect moonlight at twilight. I like the scale of it. It is huge...always a plant that I, at 6'3" can look up to. Its downfall is that you can easily lacerate your forearms when it is time to remove its faded skeleton in August after it has gone to seed.

Eryngium giganteum, known as Miss Willmott's Ghost, is a sea holly that has grey foliage with jagged edges and pale blue flowers. Garden legend has it that famed English plantswoman Ellen Willmott, who had an appropriately prickly disposition, would carry seeds in her pocket and secretly scatter them in the gardens she visited. I love the texture that Miss Willmott's Ghost provides in my borders. One of the best features of biennials is that they have an uncanny ability to seed themselves in precisely the location they are needed most. They add a note of spontaneity in gardens that tend to be too perfectly orchestrated.