Book:
Michael A. Dirr, Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propagation and Uses
Really useful book!
The chapter of plant morphology is very helpful to remember the terms to describe the plants. Pictures very explicit. I can also learn from the representation of the pictures in the book so that I can draw the sketches better.
All the plants are ordered alphabatically. Almost every infomation needed for landscape architects are covered in the book such as cultivation, size, texture, cultivars, etc.
However, not all plants have pictures. But basically I think this book is perfect.
websites:
Bean’s Trees and Shrubs
http://www.beanstreesandshrubs.org/
Although the website covers a wide range of plants and a lot of useful informations, it may take the reader a lot of time to find the infomation because it is written in long paragraphs.
There are no pictures in the website.
Royal Horticultural Society
The website is pretty helpful. The information is clearly shown. The website covers a wide range of plants.
The plant range is shown instead of USDA hardness zones. The garden usage and limiation of each plants are not mentioned. Each plant has just one picture. It’s better to have more.