GROWER MUST TEST His LOCAL CLIMATE. 19 



may cross contour lines going westward when a coast mountain 

 barrier is unbroken, and eastward when a gap in this barrier occurs, 

 because the exclusion or admission of ocean influences tend generally 

 toward the reduction of summer heat and winter cold. 



But a tendency toward equality in temperature does not secure the 

 best results from all plants. For example the free access of the ocean 

 temperatures in the coast district of the upper part of the state denies 

 oleanders, Cape jasmines, etc., the high summer temperature which 

 develops their freest flowering, while it does give heat enough for 

 grand blooming of geraniums, camellias, etc., with which the winter 

 temperature does not interfere. Thus a district outlined on the basis 

 of full suitability for the Cape jasmine might exclude the geranium 

 from territory in which it glories in summer and draw it into places 

 where it would need winter protection. If outlined on the basis of 

 the geranium or the camellia, it would bring the Cape jasmine into 

 some regions in which it would be a sorry sight because of un- 

 developed blossoms, while if outlined on the basis of the camellia it 

 would disregard the weakness of both the Cape jasmine and the 

 geranium. Thus a few common plants are used to indicate differences 

 which are narrow by the thermometer but still determinative of 

 degrees of satisfaction to the grower from the point of view of all-the- 

 year hardiness and best blooming. Many other plants could be used 

 to illustrate the same differentiation in local climatic conditions and all 

 of them would still be counted tender or semi-tropical from the point 

 of view of a wintry climate. 



The Grower's Attitude. It is hoped that the instances which have 

 been cited will demonstrate the fact that division of California into 

 districts of equal suitability to flowering plants is exceedingly dif- 

 ficult even if it should some day be shown to be, possible to some 

 edifying degree. Until such guidance is available, the only reasonable 

 advice which can 'be given to the amateur is: "prove all things, hold 

 fast that which is good." Learn from observation of older plantings 

 of trees and shrubs which have received fair treatment, learn from 

 current experience and observation the behavior of herbaceous plants 

 which interest you. Maintain a fairly critical and discriminatory at- 

 titude and a high standard of excellence, above all, do not deceive 

 yourself by regarding a thing of the best quality simply because it is 

 of your own growing. 



Absolute Elevation May Be a Barrier. In all speculations con- 

 cerning the suitability of this or that situation in California for the 

 growth of the flowers which you enjoy, two general facts are comfort- 

 ing and suggestive. First, California climatic conditions are as a 

 whole very favorable, as has already been suggested: second, defects 

 or ill-adaptations are, as a rule, slight and capable of modification by 



