My fascination with germination: keeping our rainforests growing.

My fascination with germination: keeping our rainforests growing.

Blog by: Tara Jeffery, Botanic Program Research Field Assistant. 

My main area of work is focusing on the production of trees for the arboretum and rewilding and restoration projects, which requires my team to venture into the forests to collect seeds from a range of tree species. To create a diverse collection of plants, it is important to use plants from different areas to fight against possible pest and disease problems. For this we have been across the Osa peninsula collecting ripe species. It can be difficult to predict when the trees have ripe fruit as many live within different microclimates, which can alter the week they are flowering and fruiting.

Tara Jeffery, Botanic Program Research Assistant working in the native tree nursery. Photo: Lucy Kleiner, Media and Communications

Once seeds are collected, we count them and take note of their mother tree. Then we clean the seeds, depending on the type of fruit that it has. Once planted we water them as needed and wait for them to germinate. Some species we collect are harder than others to germinate. For example, the Anthodiscus chocoensis’ seed pod carries between 6-12 seeds, but only one of them will germinate, which can take 6 to 18 months, so patience is a virtue. There are also some species on our list that only produce seeds every few years, the extreme of this is Tachigali versicolor which grows up to 45 m but once it produces seed the tree dies, this is why it is locally called “Reseco” (the suicide tree).

Seedlings of the Cambiar tree (Capaifera cambiar) germinated from seeds collected from mother trees in our nursery. The sap of the Cambiar tree is aromatic and used as incense. Photo: Lucy Kleiner





To help with the protection of these threatened species, we are commencing germination trials, to help future initiatives on the best practices for each of the species. We will follow up with secondary trials looking to improve survival rates through introduction of different mixtures of nutrients. As many of the species we are looking at don’t have much information written about them, it is a puzzle as to what each species requires, but that is part of the fun.

Irrigation system at the native tree nursery. Photo: Lucy Kleiner.