Despite the devastation that heavy rains and floods have wreaked on large parts of the Cederberg area in the Western Cape in recent weeks, the rooibos fields remain largely intact.
The road to Citrusdal, often described as the gateway to the rooibos valley, was washed away by torrential rain; this left many residents stranded for days with no way to get in or out of town.
Martin Bergh, chairman of the SA Rooibos Council (SARC), says apart from some nurseries that have suffered losses, no damage reports have been received from rooibos lands.
“Typical rainfall for the rooibos production area is 200 to 600 mm per year. June was very wet, and most areas are already approaching their full year average.
“Although winter typically marks the start of the rooibos planting season – because it requires adequate soil moisture for germination and regular follow-up rains to thrive – farmers now need to manage their timing well. It does not help to plant new seedlings in oversaturated soil that cannot drain,” says Bergh.
According to Bergh, few farmers started planting new fields, as seedlings would wash away.
“With more rain predicted for July, the soil should remain saturated, giving farmers a chance to plant well into August.
“The more mature fields also depend on winter rains for growth. A balanced interaction between sun and rain ensures a stable and healthy rooibos yield,” says Bergh.
He believes the recent rains will benefit the higher-lying rooibos fields on the mountain slopes where well-drained soil with low clay levels will ensure healthy growth as soon as temperatures start to rise.
“Rooibos root systems are usually found at a depth of one meter, lower-lying fields with shallow soil levels and clay that occurs at a depth of 60 to 80 cm are therefore negatively affected by the flooding because the soil does not drain well and the excess water causes the plants to die.”
Bergh says these fields usually produce only two good harvests, after which the plant yield drops radically.
“Extremely cold weather also affects vegetation, but the biggest challenge is managing the excessive weeds after so much rain; if not removed quickly, it becomes impossible to contain later.”
For now, farmers welcome the wet conditions, says Bergh.
“Full dams are critical as the return of (the weather phenomenon) El Niño to South Africa is predicted during the second half of the year.”
Climate models indicate that these weather events can be expected more frequently in the future, creating extremely hot and dry conditions.
Bergh says that although attempts have been made in the past to grow rooibos in Argentina, the USA, China and Australia, none of the countries have succeeded.
“Rooibos only grows in the Cederberg region, which remains the only part of the world where it is commercially viable.”
As such, the European Commission has given rooibos the status of a protected designation of origin (PDO) and geographical indicator (GI) in the EU register.
According to Bergh, PDOs recognize the specificity of the country of origin of a product and the transparency for consumers regarding its authenticity.
“The combination of the Cederberg region’s climate, soil and micro-organisms creates a unique terroir, which – just like in the wine industry – plays a significant role in determining the taste, color and aroma of a high-quality wine.” product play.”
The entire rooibos production region is constantly affected by drought due to the Mediterranean ecosystem. Average surface temperature increases in the future are likely to affect the growth and physiology of many plants, including rooibos – something the rooibos industry is watching closely.
Bergh says climate models consistently predict an average increase of 2.7 °C to 3.2 °C in annual temperatures in the Cederberg region, while projections for rainfall differ.
“Winter rainfall varies from decreases of 52 mm to increases of 32 mm.
“The model for interdisciplinary research on climate (MIROC) consistently produces the most accurate forecasts, projecting less drastic temperature rises and an increase in winter rain.”
According to Bergh, mean averages for an intermediate future period (2041-2070) indicate that rooibos suitability will remain the same in the higher elevation areas of the traditional rooibos production belt.
“In the western areas along the coast, significant decreases are predicted, especially in the lower-lying regions.
“Across all scenarios, the most significant increases in suitability are expected in the mountainous region to the south, indicating a general shift southwards and to higher elevations.
“Redwood farming in cooler and wetter areas further south is being considered in the future to ensure better growth and higher yields,” says Bergh.