Variegated plants are a common addition to gardens, particularly ornamental ones. Their distinct ability to add something new to a block of greenery draws in many owners, especially those growing indoors who may not have the resources to care for flowering plants. However, like any plant, variegated plants have their own care needs which owners must meet in order to have a thriving garden. As such, this is a guide to types of variegated plants, their care, and the ways in which they might differ from non-variegated plants.
Defining Variegation
Variegation describes the occurrence of more than one colour on the surface of a plant’s leaves. Most sources will cite the following reasons for variegation: chimerical, pigmentary, and pathological. These all alter the physiology of the plant, so the temporary changes observed when adding food colouring to a plant’s nutrients cannot be described as variegation.
Chimerical
Chimerical is used in literature to refer to something fantastical and unrealistic, but in scientific terms, it refers to a whole being which contains and expresses two sets of distinct genetic material. Usually, this is deliberate on the part of a gardener or farmer, who will take cuttings from plant tissue and graft them onto a separate plant without altering the tissue itself. However, it can occur in nature, usually due to a genetic mutation during reproduction; depending on the mutation in question, future offspring may not inherit the variegation.
Pigmentary
In some plants, variegation occurs when green pigment is present, but the plant appears to be a different colour due to the presence of other pigment, such as in the deep purple False Shamrock plant. This can be compared to simple eye colour variations in humans, wherein people with more pigment have brown eyes and those with very little pigment have blue eyes. Usually, plants with pigmentary variegation have considerable variance within populations.
Pathological
Easily the stickiest type of variegation, pathological variegation is a type of colour change which occurs when the plant is infected with a pathogen, usually a virus. Plants which are variegated for this reason usually aren’t continually propagated due to the infection’s potential to damage the plant and the risk of infecting other plants, but there are certain harmless viruses which are spread deliberately, with the end product being sold to consumers as a subspecies.
Common Variegated Plants
Variegated plants are extremely popular, and the result of this is that many gardening websites offer search engines capable of filtering specifically for variegated plants.
Gardener’s World – https://www.gardenersworld.com/search/plants/?colour-foliage=variegation
Simply typing ‘variegation’ into the BBC’s Gardener’s World search engine will pull up hundreds of results, and those looking for information can choose between articles, plants, and even offers on plants for sale.
Although the search engine doesn’t appear to allow for more than one term for filtering, the information upon clicking on each plant is relatively comprehensive.
The wealth of results websites like these offer can be daunting, which is why it’s helpful to have an idea of some common plants which display colour variegation.
Ivy (Hedera)
Both English and Irish Ivy may display variegation. In this case, it will show as a faded light green border around a deep green centre. The great thing about Ivy (for those wanting to grow it, at least), is that it grows almost anywhere and requires little maintenance. Compared to many variegated plants, this makes any species of Ivy great for beginners!
Purple Shamrock / False Shamrock (Oxalis Triangularis)
The Purple Shamrock or False Shamrock is an intriguing example of the pigmentary subtype of variegation. Each leaf is shaped like a very pointy clover (thus why it’s called the False Shamrock), but this plant’s intrigue lies in its colour, which is very often a deep, rich purple. True to its variegation occurring due to the amount of pigment it contains; the False Shamrock may also display with completely green leaves. When looking closely at some purple variations of the plant, one might also notice that the very centre of each leaf is a much more vivid purple than the outer borders of the leaf.
Caladium
The Caladium genus displays an entire subgroup of extremely fancy variegated plants. Although they have many care needs, especially for those in cooler climates, each species of Caladium more than makes up for it with intense leaves coloured in pink, white, or red, often made more striking by sections of leaf with green veins or other pigment.
Caring for Variegated Plants
Most pigmentary variegated plants and successful chimeras are tropical, with many of them found in the wild across rainforest floors. This means that they are often very tender to cold or dry conditions. Variegated plants need a great deal of light, especially if they are variegated with colours other than green. This is because leaves require chlorophyll, which makes them green, to help them synthesise energy from light – a plant with a lot of variegation will produce less chlorophyll.
What if a Plant Loses its Variegation?
In many cases, a plant will lose its variegation due to the lack of light described above. In such situations, the plant’s leaves will usually revert to being singularly coloured. Fixing this is as simple as increasing the amount of light the plant receives and the plant’s colour should go back to normal within a few months.
However, there are situations where a plant’s loss of variegation is irreversible. Genetics are tricky, and sometimes as a plant grows, it experiences genetic mutations which alter its colouring – especially in plants which aren’t asexual. Chimeras may also experience this if the non-variegated leaves hold genetic dominance. In these cases, some gardeners will recommend removing the non-variegated shoots from the plant to allow the variegated chimera to flourish.
A Word on Pathological Variegation
Prospective owners should be particularly careful of pathological variegation, which can sometimes be used to sell a plant as a subspecies when its colouring is really due to a virus. Although some viruses which cause variegation are harmless and self-containing, others may be damaging to other plants if spread, and others may be altogether harmful. As such, it’s really important for owners to research plants before buying them – a rare subspecies about which there is no information online probably isn’t the great catch it seems to be. Asking the seller plenty of questions about the origins of a suspicious plant can often be a helpful way to determine whether the plant’s variegation is harmful or not (some sellers may even be open about pathological variegation)! Even when armed with plenty of research, owners should always quarantine new plants for at least a month before introducing them to the rest of the garden, whether variegated or not!
To Close
Variegated plants are undeniably quirky and are often quite beautiful. Although their care can sometimes be trying for busy owners, they will certainly reciprocate a devoted owner’s efforts. A well cared-for variegated plant will provide a technicolour tone to a garden – and makes a great talking point when entertaining guests!