They play an important part in masking structures which are unsightly, and raise the flower level far higher than is normally achieved by shrubs, and many trees. Also they add an architectural dimension to the garden, and none more so than the aroids. Aroids are the large-leaved residents of the rain forest. Large leaved because they don’t waste any light at all. Most of you know the Swiss Cheese plants such as Monstera deliciosa, and the Scindapsus and Philodendrons which are popular throughout the world. Monstera is called the Swiss cheese plant of course because the leaves are full of holes.
Other aroids, instead of developing holes throughout the leaf system, merely allow them to develop strips. This habit is to permit them to shed the enormous amounts of rain which fall on them through the canopy throughout the equatorial year. Most climbers tend to grow towards the light. However this is not so with many of the aroids, the seedlings of which tend to grow away from it, swaying about, I suppose, like a snake until they make contact with a suitable tree trunk. Then their growth pattern changes and they start growing towards the light. As they grow towards the light they produce their heart-shaped leaves to absorb every bit of light they can get hold of, and their stems start to produce roots which anchor themselves to the trunk.
In this way aroids can reach enormous heights, and as they become more exposed to the torrents of rain so they start to develop holes in their leaves to help shed the water, and their root system develops long roots which eventually grow down to the forest floor. On the way down they are able to absorb moisture from the saturated air.
It is not always possible to appreciate all this in the garden, as aroids are not encouraged to get to great heights, but nevertheless in nature that is what happens.
I was very thankful when I was a lad that I never needed to be given castor oil, a natural product that was supposed to give the most spectacular results for those unfortunate people who suffered from over-eating. I later came to understand that it came from the castor oil plant. Even later I came to know and appreciate the ornamental value of the castor oil plant (Ricinus communis).
In England it featured prominently as one of those valuable plants that were used as ‘dot’ plants in a bedding scheme to give height and character to the display, rather like half-standard fuchsias and the marmalade plant (Streptosolen jamesonii) were used. Ricinus has large spectacular palmate leaves which are green in the ‘ordinary’ species but which are dark red in the variety called Ricinus communis gibsonii. Ricinus bears very attractive fruit in either form, and responds best to a regime of rich soil, and full sun. The oil used to be used as a lubricant in heavy machinery and aeroplane engines, as well as a medicine.
Until next week may your God go with you wherever you may be.