The sky blue flowers of the garden forget-me-not (Myosotis sylvatica) are familiar to most gardeners. It is a very common plant of flower gardens, although it is more trouble than it is worth in New Zealand (where mildew besets plants, and it becomes an annoying weed). The late winter/spring appearance of its flowers are evocative of English and European woodlands, to where it is native1.
It will therefore come as a surprise to many that New Zealand is a major centre of diversity for this genus. Out of a worldwide figure of approximately 100 Myosotis species, around 40 are native to New Zealand2, with all but two of those species confined to our shores. This diversity increases further when we take into account the distinct varieties that occur within some of our species.
Several New Zealand species of Myosotis make fine garden plants, although they are still little known by most gardeners. In addition to their potential for cultivation, some knowledge of our native forget-me-nots can enrich one’s experience of our wild places; as some of the native species are stunning when in flower (the most notable example being the remarkable bronze forget-me-not, Myosotis macrantha).
It should be noted here that the commonly cultivated Chatham Island Forget-me-not, Myosotidium hortensia, is not part of this genus. It actually constitutes its own genus, which is found nowhere else in the world (outside the Chatham Islands). It is therefore not included in this article, but may be featured in a future plant profile.
Of the native forget-me-nots that are suited to cultivation, several are alpine or montane species which are best grown in areas of relatively low humidity (such as in more southern or elevated parts of New Zealand). However, several species, including Myosotis eximia and Myosotis pottsiana, perform well even in the north (in suitable conditions).
An additional aspect to the cultivation of native forget-me-nots is that a large number of our species are either rare or acutely threatened in the wild. Therefore, growing them contributes to making their existence better known, and in some cases towards preserving the genetic diversity of species. It also contributes to the work of nurseries such as Oratia Native Plant Nursery, who were actively concerned with making tangible contributions towards the conservation of native plants over several decades.
This nationally endangered forget-me-not is native to Auckland’s west coast, with its close relative, M. pansa subsp. praeceps occurring sporadically on the western coast of the King Country and northern Taranaki. It always grows close to the sea, within open forest or scrub, and more open habitats such as the base of cliffs – areas which, importantly, have reasonably good air movement and are not excessively shaded or humid. Its vibrant green foliage and well presented white flowers (which appear over a long period in summer) render it a very beautiful plant; one which is also, fortuitously, well adapted to garden use.
M. pansa subsp. pansa is one of many examples of a horticultural variation on the ‘Cassandra Complex’3; a plant that despite being heartily recommended by esteemed authors like Lawrie Metcalf, is too seldom taken up by gardeners or horticulturists. Our horticultural and botanical literature is filled with similar cases, extending back into the writings of Thomas Cheeseman or Leonard Cockayne, almost a hundred years ago. This is a sentiment that Muriel Fisher expressed regularly in her classic work on native plants for gardens; and is not a complaint, but rather an affirmation of the huge potential (and importance) that lies in investigating a wider range of the New Zealand flora than that which is commonly represented in gardens or landscaping.
Myosotis pansa subsp. pansa grows in a similar manner to the classic garden forget-me-not, insofar as it is a short-lived perennial which self-seeds freely once established. It is, however, superior to its European relative as its foliage does not become bulky and scruffy in the way that M. sylvatica does at the end of a season. In line with its natural habitat (and the natural tendency of many forget-me-nots towards being affected by mildew), it should be grown in an area with reasonable air movement and partial shade.
Accommodating a short-lived, self-seeding species (like M. pansa subsp. pansa) is not especially in line with many modern garden styles, in which dynamism is considered counteractive. However, within naturalistic or flower gardens, such plants perform the important role of a ‘filler’ plant. ‘Fillers’ tend to choose their own spot within a garden after a few generations, imbuing gardens with a sense of spontaneity. In addition to its aesthetic value, gardeners or landscapers make a small but real contribution towards the conservation of this highly endangered species, through cultivating it.