With the UN decade of restoration and the Kenyan target to grow 15 billion trees, we have to get it right from the source, that is, at our tree nurseries because quality and adaptable seeds are where conservation meets community needs on restoration. Follow the story with Brian Otieno, Project Officer in charge of Conservation Education at Laikipia Wildlife Forum, and John Kang’ethe, Project Manager at Likii Water Resource Users Association(WRUA), embarking on a journey to refine their tree nursery management skills to come back and train other nursery operators and managers.
After evaluation by CIFOR –ICRAF, our nurseries were considered to be among the best for restoration, and they supported us in attending the Restoration Champions Tree Nursery Management Training from March 24 to 26, 2025. Hosted at Breeze Hotel and complemented by practical sessions at the Laikipia County Kenya Forest Service tree nursery in Nyahururu, the training was expertly facilitated by Sylvia Buleti (QT Seed Technical Manager, ICRAF) and Joshua Musau (QT Seed Africa Technical Consultant for Nurseries).
This training was eye-opening and reinforced the essentials of tree nursery establishment and management. Whether you are a nursery manager, an attendant, or someone planning to start a nursery, here are key takeaways to ensure success in your venture.
Setting Up a Tree Nursery: The Basics
A well-planned nursery starts with determining the appropriate size, which depends on available space, resources, and target production. Site preparation involves selecting a location with good drainage, access to water, and protection from strong winds. Establishing nursery structures such as shade nets, water supply systems, and raised beds is crucial. The nursery layout should include seedbeds for germination and seedling beds for transplanting. Tools like watering cans, pruning shears, and germination trays are indispensable.
Tree Nursery Operations and Practices
A tree nursery calendar is essential for scheduling soil collection, seed sowing, and transplanting activities. Soil preparation requires a balanced mixture of forest soil, compost manure, and sand to enhance aeration and nutrient content. Proper pot filling ensures good root development while pricking out (transferring seedlings from seedbeds to pots), which must be done gently to avoid root damage. Watering, root pruning, and hardening off (gradually exposing seedlings to outdoor conditions) are critical for strong, adaptable plants.
Seed Sourcing, Handling, and Propagation
Quality seeds determine the quality of seedlings. Seed collection should be done from superior, disease-free mother trees, ensuring genetic diversity by collecting from different stands. Standard seed collection methods include natural seed fall, climbing, shaking, and using pole implements. Processing involves sorting, extraction, cleaning, drying, and proper storage. Some seeds require special treatments to break dormancy:
Cold water soaking: Vitex keniensis (48hrs), Acacia xanthophloea (24hrs), Acacia melifera (12hrs), Senna siamea (12hrs)
Hot water soaking: Olea africana (48hrs)
Nicking (breaking hard coats): Red cedar, Podocarpus falcatus, Sesbania sesban
Crushing: Dombea
Vegetative Propagation: Grafting, Layering, and Budding
For those keen on propagating specific tree species, vegetative propagation ensures high-quality, fast-growing plants. Grafting involves joining a scion (a shoot from a superior tree) with a rootstock (a sturdy seedling). The scion should be 10-20cm long, with 2-3 buds, disease-free, and cut just before the rainy season. Proper alignment of the vascular cambium layers is key for successful grafting. Common techniques include:
Wedge grafting: Cutting both scion and rootstock in a wedge shape for secure attachment.
Splice grafting: Making matching diagonal cuts on both parts for a snug fit.
LWF’s Brian Otieno joins fellow restoration champions in a hands-on grafting session during the Tree Nursery Management Training in Nyahururu
Pest and Disease Management in the Nursery
A healthy nursery requires vigilance against pests and diseases. Common threats include root-knot nematodes, scale insects, and aphids, while fungal infections like damping-off (Rhizoctonia, Fusarium) pose serious risks. Integrated Pest Management (IPM) emphasizes nursery hygiene, proper spacing, and soil sterilization through solarization. Regular monitoring and early intervention prevent significant losses.
As tree nursery managers, we left the training with invaluable knowledge to enhance our operations. Whether nurturing a small backyard nursery or managing a large-scale operation, these insights will help you establish a productive and viable nursery. Let’s continue to grow trees, restore our landscapes, and contribute to a greener future for Laikipia and beyond!
