A perennial garden w/out annuals/woody plants is a gruesome thing
This is more or less a direct quote from Allan Armitage, who is not a fan of the all-perennial garden.
I think "gruesome" may be pushing it, but I reserve space in the perennial garden every year for annuals and subtropicals (tender Salvias, cannas and experiments not quite ready for prime time in the main temperennial bed have been fun to play with). Shrubs (including several varieties of Itea and Fothergilla major and Cotinus 'Golden Spirit') provide multiseason interest, while tall ornamental grasses (such as Miscanthus 'Cabaret', M. 'Variegatus' and Panicum 'Dallas Blues') and woody perennials that generally overwinter well (i.e. dwarf crepe myrtle and Caryopteris 'Worcester Gold) also provide dominant themes and contrasts throughout the growing season.
I suppose they add winter structure as well, but since my usual gardening activities in this season involve the fluorescent light garden and reading seed catalogues, I don't pay much attention to what is standing tall above the snow and/or mud.
So, do you agree with Armitage? And if so, what non-perennials help make your gardens special?
The Itea in the above photo ("Henry's Garnet") traveled with me to Ohio from Texas. The foreground plant is Brunnera macrophylla.