Agaves: Nature’s Architectural Wonders

Agaves are weird but alluring plant camels that are great focal plants in the garden and irresistible to the dedicated succulent collector. Agaves really are nature’s architectural wonders! Editor Tanya Visser reveals why she has become such an agave junky…

I call agaves my ‘blueprint of God’. The most spectacular feat of nature is the imprint of the thorns and leaf margins first visible as the soft leaves start to uncurl from the growth point and which stay on the leaves even as they mature into adult form. I can take pictures of these imprints forever and they never stop fascinating me! 

Nature’s Architectural Wonders

There is just no denying that certain agave species and cultivars are so striking that they completely change the immediate landscape with their presence. This is a diverse genus when it comes to shapes, textures and foliage colours, such colours as dull green, steel-grey, iridescent silvery-blue and even variegated with white, cream or yellow are all thrown in.

A common characteristic of these succulents is the symmetrical rosette of succulent and fibrous leaves, which can be long, thin and grass-like, squat and finger-like, or very large, broad and heavy. Generally, the fleshy and fibrous leaves of all species end in sharp points (sometimes extremely sharp terminal spines), while those of some species also have sharp marginal teeth, making them real bully plants that have to be handled with care. 

The Century Plant

Agaves are monocarpic, which means they only flower once after which they die – this is nothing to worry about though! In some species the mother plant will feverishly produce several pups (suckers) at the base of the rosette before she pushes out a tall inflorescence with a mast-like pole topped with a spike of nectar-rich flowers. In others, a bulbil (plantlet) develops at the base of each flower that will fall off and root where it lands on the soil.

Agaves are very slow-growing and can take many years to flower, hence the common name of  ‘century plant’ – although it is more a case of between 10 and 40 years, depending on the species. They are not really prone to flowering in pots, which also inhibits those guys that grow and sucker too enthusiastically. Since mostly native to the hot and arid regions of the Americas, they are extremely drought and heat resistant and will also tolerate quite low temperatures. They are not really susceptible to pests or disease (unless over-watered) and are perfect for pots of all sizes to display in full sun to light shade. 

READ MORE: Agave schidigera and Agave geminiflora

Here are my favourites

Agave parryi 
Its grey-green foliage is just spectacular and the contrast of the black point tip or thorn is so incredibly striking against the grey foliage. This plant is very slow growing but so worth it. 

Agave guiengola ‘Crème brûlée’
The broad green leaves with silky cream margins make it a must-have! 

Agave potatorum ‘Kichijokan’ 
Not one plant’s colouration is the same, so if you see one you like then get it. The strong cream margins simply get better with age. It has a mature height and width of no more than 30 – 40cm and is a stunning garden or container plant. 

Agave toumeyana 
From central Arizona, this is a compact agave that reaches no more than 50cm in height, but the plants produce masses of narrow leaves with gorgeous markings and white curling threads. 

Agave lophantha ‘Quadricolor’ 
Short and compact, no more than 50 x 50cm, with the most striking yellow-edged leaves and red teeth on the margins.

Agave victoriae-reginae 
A very long-lived, exceptionally slow-growing succulent with short, triangular leaves that are hard and leathery with thorny tips. Interesting white lines cross the leaves, which are edged in white as well, in a web-like pattern.

I’ve got a pup to replant

My Agave potatorum ‘Kichijokan’ made a cute new pup that resembles the mother plant perfectly, and I decided to remove it and move it into a small pot to grow on. Most agaves (there are some exceptions) that have grown to maturity produce lots of pups or suckers around the base of the mother rosette, and these can be removed to grow more of them. 

All agaves have shallow rhizomatous root systems to enable them to harvest life-giving moisture and nutrients in the dry areas they inhabit naturally. 

The rhizomatous root system is actually a horizontal underground plant stem capable of producing the shoot and root system of a new plant.

To remove a pup from its mother, use a narrow weeding hand trowel, screwdriver or chisel to gently pry it loose without you having to do battle with any sharp thorns.

Fill up a pot with barely moist soil mix and take care to plant the young pup not too deeply. Leave it on the dry side and in a lightly shaded warm place for a few days to settle in before watering the plant. 

Troubleshooting

I very occasionally find a mealybug spot here and there, which I control with a simple spray of Oleum. These plants are incredibly resilient and the only other problem I have is when we have a very wet summer. This can cause some of the lower leaves to get unsightly blemishes from too much water, in which case I simply use a small garden saw to cut them off. 

My preferred soil medium for potted agaves 

This simple mix has been my go-to medium for many years. In a large pot, add gravel for drainage and a coarse potting soil to which I add some coarse silica sand, as it makes for even better drainage. Add a few handfuls of Atlantic Bio Ocean and a good dose of bonemeal and you are on your way. 

READ MORE: Find out more about Agave Victoria-reginae here

Did you know?

Some of the Agave species (A. americana and A. sisalana) that were planted in days gone by in parts of South Africa, now appear on the invasive vegetation list. They were imported from the arid regions of Mexico and tropical America, and in South Africa were discovered to have multiple uses, from medicinal to functional.

They’re used in the arid regions of the Karoo as fodder for cattle, to prevent soil erosion, to form secure hedges around cattle pens and to provide nectar for honey production. These plants, while fairly harmless in desert landscapes, are practically indestructible and when they escape to temperate and subtropical climates with high rainfall, they become a serious threat to the natural habitat and its biodiversity. 

Mature A. americana and other agaves are harvested and de-foliaged, and the stem, which resembles a pineapple (called a piña) is then steamed before being distilled into an alcoholic drink called mezcal. Those of A. tequilana var. azul (true blue agave or Weber’s Azul) are used in Mexico to distil tequila. I unfortunately do not have a distillable tequila agave yet…