Story and photos by Cathy Watson
Indigenous trees are a must if you want a resilient garden that survives drought and other climate stresses and looks vibrant all year round. Since indigenous trees co-evolve with local birds, insects, and other life forms, they also bring far more biodiversity than exotic trees.
“Indigenous trees bring many benefits to nature and humanity,” says National Museums of Kenya botanist Geoffrey Mwachala. “In addition to aesthetic values, they stabilize soil and improve its structure while providing habitat for epiphytic plants, insects, birds, and small mammals. These, in turn, provide pollination and seed dispersal services for crops and wild species.”
But everyone wants flowers. So here are six trees with blossoms native mainly to East Africa. Going Indigenous does not mean sacrificing flowers—far from it.
Gardenias belong to the plant genus that includes coffee and are indigenous to Asia, Africa and the Pacific. East Africa has two indigenous species – Gardenia ternifolia and Gardenia volkensii. Either one is a blessing to your garden. Both have showy white flowers that sometimes turn yellow. Both are short trees with tough wood that can be used for knife handles and other tools and have medicinal properties. Maasai women use their tough and often twisted branches to block entrances to their animal enclosures. In Kiswahili, they are both called Mkimwewe.
With clusters of large pink-purple flowers, Cape Chestnut (Caledendrum capensis) is widespread in Kenya with names in 10 Kenyan languages, from Yangu in Kamba to Ocharasliit in Pokot. In Uganda, it is found only in scattered woodlands in Mbarara, although a few grow behind the High Court in Kampala. Thriving between 1200-2200 m, it flowers throughout the year, has a smooth grey bark, no troublesome roots, and reaches just 15 meters. It is newly planted at Jomo Kenyatta International Airport in Nairobi and has been flowering for less than two years. It is a beautiful African tree with large, easy-to-collect and germinate seeds.
Rothmania urcelliformis is a small 2-9m tree covered with upright trumpet-like white flowers. Part of Kenya’s understory of drier forests grows from Embu to Samburu. In Nairobi, I first saw it in the garden of newspaper editor Joe Odindo and then in Karura. In Uganda, it is common in Kibale Forest, where it is called Munyanburu. It is said to also grow on Karamoja’s Mt Kadam. Remove the pulp from the seed. It germinates without treatment. “This species, when in full bloom, is a wonderful sight,” says Useful Trees and Shrubs of Uganda. It intercrops and grows well with coffee.
The local names of Syzigium cordatum are Muzitu in Luganda and Muriru in Gikuyu. A very hardy, fast-growing tree found in East Africa from sea level to 2200m, it has surprisingly pretty clusters of delicate white flowers that turn into edible fruits that can be made into a drink, according to Useful Trees and Shrubs of Kenya. It can also provide bee forage, tool handles, medicine, tannin, poles and charcoal if needed. Syzygium cordatum is a cousin of Syzigium cuminii, the well-known Indian fruit tree naturalized in East Africa called Jambula in Uganda or Mzambarau in Kenya. Another cousin of Syzigium cordatum is the forest tree Syzigium guineense, which grows across Africa and has edible fruit and leaves. Let us plant more of this genus of valuable, pretty, multipurpose trees.
Millettia dura is a medium-sized tree that reaches up to 15m. Mwonga in Kisii and Mwanga in Meru have showy sprays of purple pea-like flowers and seed pods that crack open with an unmistakable explosive bang. In so many ways, it is surprising that this tree is not planted more. It is termite resistant, fast-growing and improves soil. Creating a dappled light, it was once promoted as a shade tree for coffee in Kenya; its relative, Millettia ferruginea, is an “important shade tree for peasant farmers growing coffee”, says Useful Trees and Shrubs of Ethiopia. If you love purple, think about planting this tree along with Cape Chestnut instead of or in addition to Jacaranda, which is a Latin American tree probably from Paraguay. More species and focusing on native species will yield far better biodiversity results.
Dombeya torrida grows to just 8m, so some call it a shrub. In East Africa, it is found in Kenya, Ethiopia, Uganda, Tanzania and Rwanda, where “it is endemic to the Albertine Rift,” according to The Woody Species of Rwanda. It has abundant flowers with white petals and red centres. These are so full of nectar that in Ethiopia, traditional bee hives are often placed on the branches of this tree. The leaves are papery, and the tree’s heavy litter provides excellent mulch. Called Boroa in Tugen in Kenya and Borowa in Sebei in Uganda, fibres of its bark can make cloth or string. It is an understory tree, so you can grow it under more giant trees.
Other abundantly flowering trees you can grow in your garden or farm are Cordia africana and African Tulip or Nandi Flame (Spathodea campanulata). However, both are still widespread, and it is always best to plant what is uncommon or even rare and threatened. Make that a rule of your planting: diversity. If all gardens have the same few species, they become like a desert for insects, birds, reptiles, amphibians, and mammals—a buffet with scarce food, a hotel with no beds.
Consider the six trees described above for farms, too. “These flowering indigenous trees can be used for agroforestry. Millettia dura has a symbiotic relationship with certain soil bacteria, which form nodules on its roots and fix atmospheric nitrogen that crops can use,” says Karura Forest restoration manager Ely Kogei.
Show nursery operators the photos of these trees and ask if they have them. Nurseries stock what is in demand so you can drive that demand. “Create a haven for birds by planting diverse indigenous beauty in your garden,” says Ethiopian landscape ecologist Ermias Betamariam.
Cathy Watson works for CIFOR-ICRAF and has been planting these species, among others, to increase tree cover and diversity along Nairobi roads since 2020.
