I consider my clumps of Japanese anemones (pronounced ah-NEM-oh-nees) to be the crowning glory of my late-season garden. Their pink and white flowers dance in the breeze for about six weeks—from the end of August to early October—associating happily with spikes of great blue lobelia (Lobelia siphilitica) and various bugbane (Actaea syn. Cimicifuga) cultivars. The overall effect is a late-season symphony of pink, white and blue—colours that are generally lacking in our predominantly golden-hued autumn beds.
Aside from their superb flowers, perhaps the most appealing attribute of Japanese anemones is that they're as easy to grow as green beans. Most cultivars will tolerate everything from full sun to deep shade, they're not particularly fussy about the soil they're planted in, they're generally rabbit resistant and they have few insect or disease problems. Nevertheless, for optimum garden performance, here are a few simple guidelines.
Japanese anemones are happiest in partly shaded conditions. I've found that an eastern exposure works well; it allows the plants to benefit from morning sun while protecting them from blazing afternoon heat. In full sun, their foliage may burn and flower colour will look washed out. Full shade produces fewer flowers, but with deep, rich colouring.
They accept a wide range of soil types—from sandy loam to heavy clay—so extraordinary measures aren't called for; however, as with any perennial, a healthy dose of organic matter added to the planting hole before installation will make for a long, floriferous life. As an added bonus, aside from the cultivar ‘Party Dress' (which doesn't do well in limy soils), Japanese anemones adapt easily to acidic, neutral or alkaline soils.
Despite their predisposition for moist soil conditions, Japanese anemones perform well without much supplementary irrigation, and indeed, in warmer zones where plants may become precocious, withholding water is the best method for keeping clumps contained. Large, double-flowered varieties usually require some discreet staking, particularly after heavy rains.
Planting and propagation
For best results, install new plants in mid-spring or early autumn. Divide established clumps in the spring as soon as the foliage emerges.
(Anemone pictured above: 'September Charm')