This paper investigates the simulation of plant growth in a virtual model using a combination of computational techniques. Equations from the GreenLab model are used to calculate the quantity of new biomass produced through photosynthesis, while a modified space colonisation algorithm is used to describe geometric growth. The geometric model is used to calculate intercepted light, which is fed back to the production equation. This simulation-modelling approach is used to generate visualisations of plant growth under varying environmental conditions and in mixed communities. The macro and micro scale virtual environment influences plant architecture and development. Semi-realistic simulation of growth is achieved across a number of plant species with the possibility of further application. The species are selected from those installed at a trial project in Sydney, Australia. Maintenance processes such as pruning and coppicing are implemented in the dynamic growth model. Challenges include increasing computational complexity when plants are simulated on a large scale site, and cost to validate growth parameters from in-situ study of plants.