Should Plumbago auriculata Be Grown As A Trimmed Hedge Or A Regular Landscaping Shrub?:

Plumbago auriculata, or Cape Plumbago, is a somewhat strange landscaping shrub. It has many fine qualities, not least its profuse blooming of sky blue flowers through most of the warm, growing season. For Mediterranean and dry climate gardeners in particular, its capacity to withstand drought, neglect and poor, alkaline soils makes it one of the most useful landscaping shrubs available. Yet it often induces negative reactions from home gardeners. Why is this?

I think the main reason is that it tends to be used incorrectly - as a trimmed hedge by a walkway for instance. As with all plants however, an understanding of its strengths and weaknesses gives one the chance of planting it in situations where it will perform well. Here are a few reasons why Plumbago auriculata is a poor choice for a trimmed hedge, and why it has sometimes earned a bad reputation for itself.

*Firstly, it looks poor at close range. If viewed at a distance, it can create a lovely splash of cool, blue color. Close up though, it tends to appear ragged and messy.

*Secondly, both its flowers and leaves are somewhat sticky, a fact that can turn the bush into a nuisance in narrow spaces.

*The plant is a major litterbug, constantly shedding its sticky leaves and flowers on the pavement, or onto parked cars.

Cape Plumbago is best planted therefore, as a large-scale ground cover, or as a foundation plant, in the more spacious areas of the garden. It grows as a loose, mounding bush to about 2 meters in height (6ft) with almost double the spread. It can be pruned back hard every few years or so, to create a more compact, dense growth habit. Established plants flower beautifully without the addition of chemical fertilizer, although adding compost once a year will always be beneficial.

Growing Requirements

Plumbago can grow in most garden soils, providing there is adequate drainage. It is sensitive to cold and is inappropriate where winter temperatures drop below -2c (28f).Its hardiness to heat and drought, make it ideal for water conserving gardens. In Mediterranean climates, it can get through the summer with virtually no irrigation, but in regions where average highs are over 35c it will benefit from about 100-200mm of extra water a year. It should not be planted in proximity to plants that need regular irrigating, as not only are its water conserving properties wasted, but is a type of shrub that actually flowers better in dry soils!