At the website http://www.kurtz-fernhout.com/ you can download PlantStudio for free.
The description from the website:
PlantStudio Botanical Illustration Software is a tool for creating 3D plant models and 2D illustrations. PlantStudio simulates herbaceous (non-woody) plants like wildflowers and cut flowers, vegetables, weeds, grasses, and herbs using a parameter-driven simulation of plant growth and structure. You can “grow” plants over their life cycles, producing lifelike images at any age. You can design, animate and breed a wide variety of plants. By using the “evolutionary arts” of variation and selection in the plant breeder, you can quickly and easily create whole families of unique plants for your 3D scenes.
For the Registration Code look at the order page.