In addition to broad differences between California and other areas oc cupied by English-speaking peoples in the Northern Hemisphere, conditions of soil and climate are very diverse within the boundaries of this common wealth and gardening practice must vary with them. N o matter how skilful and successful a man may be in his particular locality, his experience can only be a safe guide to those who happen to work under Similar conditions. There fore a suggestive treatise must analyze the local conditions and practice and translate them into terms of wide applicability. To do this it is necessary that the principles underlying the successful practice should be discerned and the significance of conditions be interpreted. That this character has been in some degree attained in this work is attested by its acceptance as a guide in all parts of California and by the sphere of popularity and usefulness it has entered in distant countries, which have resemblance to California in climatic conditions and desire to establish similar industries upon them. The writer has had opportunity for wide collection of data, and for ex tended personal observation as well, and his effort has been continually in Spirited by enthusiastic delight in the subject itself, gained from his own garden work.