This post was originally published on 30 July 2015
Portulacaria afra, better known as Spekboom, is an indigenous evergreen succulent tree that is predominantly found in the Eastern Cape. The tree forms an important part of the Valley Thicket Biome as it is both fire-resistant and water-wise.
Climate & Photosynthesis
Spekboom is able to adapt its process of photosynthesis depending on its conditions and availability of water. In wet conditions it uses the same system as rainforest plants and switches its system to one used by desert cacti in dry conditions. Through this switch, it is able to store solar energy to photosynthesise at night when temperatures are cooler.
Studies have shown that a single hectare of Spekboom is able to convert 4.2 tons of carbon-dioxide into oxygen per year. The tree’s carbon-storing capabilities makes it up to 10 times more effective than any tropical rain forest.
Structure & Growth
Spekboom flourishes in warm summers and areas where rainfall is between 250 and 375mm per year. During Spring, star-shaped pink or light purple flowers appear which can be used to make honey. The tree’s cork-like roots measure up to 20cm in diameter and can reach heights of between 2.5 and 4.5m, making it ideal to use as a natural hedge.
Spekboom is rich in manganese, cobalt and magnesium. It also contains micro elements, iodine and selenium which act as an antioxidant. The leaves have a refreshing, slightly tart, lemony taste and can be used to treat a number of ailments including heart burn, dehydration, exhaustion and heat stroke. The leaves are typically suckled on or can be eaten as part of a salad.
In order to propagate Spekboom, cut a small branch just below a node. Remove the bottom leaves and dip the end of the stem into hormone powder. Create a small hole in soil and plant the stem. New roots will form on the stems within 3-4 weeks. Plant the stems in the desired locations and fill the holes with soil. Water the stems well to ensure that the roots settle. Spekboom grows best over a period of three years or greater and can reach ages of up to a 100 years.