Ewen's garden

A collection of columns, paintings and photographs about gardening on an offshore island in New Zealand.

Friday, April 22, 2005


I am still banging on about blue, but nearly there. Did I say there were not so many plants with blue flowers? One worth a mention and especially suited to our climate is ceanothus or Californian lilac Ceanothus sp. as the common name suggests it is native to California and so is well adapted to our dry summers. Ceanothus usually forms a small shrub, but some specimens have a low ground hugging habit suiting them to ground cover. The plants need pruning after flowering to keep them from becoming too leggy and open in the middle.

There is another plant with unforgettable blue flowers and that is our own Chatham Island forget-me-not Myosotidium hortensia. This large herb has glossy green rhubarb shaped leaves and large heads of blue and white forget-me-not flowers, the clusters being about 10 to 15 cm across. Unfortunately it is a difficult plant for our dry summers and mild winters; I would be very interested if anyone has success with it here on our island. In Wellington at the Otari Plant Museum there are wonderful drifts of it growing beneath trees. My mother had some growing on the farm in the south Wairarapa, where they looked splendid at the end of the lawn beneath a tree and a golden privet hedge as backdrop.

Speaking of forget-me-nots, of course there are many bedding plants of blues shades including: Lobelia, aster, pansies, ageratum, campanula, polyanthus, anemone and larkspur to name a few. For the water there is pontideria pontideria cordata with arrow shaped leaves and spikes of blue flowers. This pond dweller can add a little vertical dimension. Another blue plant for the pond is a tropical water lily Nymphaea sp. This flower is sometimes used in the cut flower industry, but like so many ‘blue’ flowers it is really a little purple.

I think this is ok, as a strictly monochromatic border may be a touch on the boring or dull side. A mix of blue and bluish purple may be more interesting to the eye, throw in one yellow flower and the whole lot will sparkle, (yellow being the complimentary colour on the colour wheel, that is opposite) bringing all those blues to life. A note of caution though; be careful with yellow as it is what is known as an advancing colour. An advancing colour is one that will attract the eye first. This trick of the eye is sometimes used to create the allusion of distance. Putting advancing colours like yellow and red (also known as warm colours) to the fore ground and the blues to the distance, helps to increase the perceived length of a border. Another trick of the eye is to make the border or path slightly narrower at the far end increasing the sense of distance. Naturally if you look back from the other end your sense of distance will be foreshortened. These ploys I have to say are more commonly found in the larger gardens, but can apply to a smaller plot, so if you are contemplating a new border have a wee think about the use of colour and perspective and have fun.

Thursday, April 07, 2005

Plumbago articulatus Posted by Hello


Last week I finished with morning glory Ipomoea learii from the tropics, there are a few more with blue flowers native to warm climates.

Firstly, there are the bromeliads that come in shades of blue although some of these may be on the purple side. One of the more stunning of these would have to be a tillandsia Tillandsia cyanea sporting a reddish spathe from which emerge the most stunning electric blue petals. The flowers commence blooming about two at a time from the base of the spathe and continue flower over a long period. The tillandsia genus is includes the Spanish moss common to the Southern USA, and survive on dust from the atmosphere rather than soil. Any roots that do occur are purely for anchorage. A good companion for this might one of the taros sporting leaves with an electric blue tinge, the exact name of these I am not sure of, but I have seen them for sale for time to time.

For subtropical blue colours there is the bird of paradise plant, Strelitzia nicolai, where the flower petals are white with a blue spathe. This plant is more likely to be grown for its showy foliage rather than blue flowers. The leaves are held in broad fan shapes the stems over time forming trunks. An example of S. nicolai can be seen out side the Anglican church in Oneroa. The only point about it is the way the old foliage persists after it is spent, requiring removal to keep it looking tidy. This could be teamed with the sky flower Thunbergia grandiflora a large fast growing subtropical vine.

Other blue flowers from a more Mediterranean climate might be the pride of Madera, Echium fastuosum with its long upright panicles of blue flowers making a lasting display in summer. Like many blue flowered plants there are other colours as well including purple and pink. E. fastuosum needs a good prune back after it has flowered to keep it from getting overly large and woody. Another suited to our dryer climate is the blue marguerite daisy Felicia amelloides has small pure blue daisies with a tiny yellow centre. Again a good cut back after flowering will help keep it compact. It will, given the chance, cascade down a bank very successfully. From South Africa, for a blue cascade is plumbago Plumbago auriculata, this pale blue vine has no problems adapting to our climate. Like with the others a good trim back will again keep in bounds. It is best when grown on some form of support but will mound it self up on itself to create a bush. There is available now a darker flowered form so keep an eye out in the nurseries for this.

While on the topic of South Africa it would be hard to go past the common old blue agapanthus Agapanthus africanus. There are now also many different forms of A. africanus now available, in varying sizes and colour from white through palest blue to deep blue. For the damper position what could be more evocative of childhood days than the hydrangea Hydrangea X macrophylla ‘Hortensia’. If you have the water for them they are great. Providing blue flowers when grown in acid soils and red to pink when grown in alkaline soil! Having soils tending toward the acid we are more likely ot have blue flowers, but with the addition of lime we can have pink ones as well.

Next time blue fades to purple and other ideas on colour.