Nowhere do flowers grow more luxuriantly, in greater variety, or through a season more prolonged than on the coasts of Oregon, Washington, and California,—soil, moisture, and temperature combining to make gardening a simpler task than it is elsewhere. The shore country of Southern California is a perpetual garden, with a climate almost unrivalled for plants and for humans. North of San Francisco the near approach of the Japan Current produces a climate quite similar to that of England, and with the exception of possibly two months (and even then an occasional Rose may bloom) flowers are found all the year round. This favored section of the Northwest nevertheless is not visited with as much sunshine as is found elsewhere, but its gardens blossom with little assistance save from the frequent rainfall, more welcome to plants than to men.
In Kansas and the other flat and fertile States of the Middle West the garden period, on account of the long, dry summers, is usually limited to the weeks from late March to late June. In the more northern temperature of the lake region gardens which flourish all summer are numerous.
The Atlantic States have a shorter blooming season than those on the Pacific coast. Throughout the South, east of New Mexico, the warm weather season is as prolonged as on the Pacific coast, and yet in the Southern States garden bloom is checked half-way through the summer by excessive heat and drought (except in the favored mountainous localities), which at least interrupt the continuous succession of flowers. For this reason gardening in the South except in spring, or in high altitudes, is generally discouraged.
Although not stated as an indisputable fact, scientifically, we are inclined to believe that the seacoast section of the Maryland peninsula is the locality in the East especially favorable to the most prolonged season of bloom. Lying between sea and bay, this particular district in the latitude for early spring and late frost enjoys also the benefit of surrounding waters, escaping thereby the parching summer climate from which gardens of the interior suffer, to the west and south and to the north, almost as far as Philadelphia.
In Maine conditions are different; April and May gardens are conspicuously absent. The flower season generally begins in mid-June and does not much exceed three months, but in that period the bloom is exceptionally luxuriant. The season is necessarily a short one, as it is throughout this latitude westward to Oregon, where after reaching the Coast or Cascade Range there is a change and the climate becomes more like that of England than Maine. Along the Atlantic coast from Maine to New Jersey, where the climate is ideal for flowers, the greatest proportion of Eastern gardens may be found, on the shore and inland as well.
So much for the general climatic effects upon flowers of the more populous districts of our vast country. A few lines will suffice to treat the climate question in connection with hedge-plants.
While the summer climate in the Southern States has not generally a salutary effect upon the flowers, yet it has favored the best development of Boxwood, Holly, and certain other choice shrubs and trees, which do not thrive well north of Philadelphia. Fine specimens of Boxwood are rare sights in New England, where the more severe winters have from time to time destroyed the top growth. Many old New England gardens show the characteristic Box-edged path, but the shrub is usually not over two feet high, and is likely to remain so unless eventually the winter climate should moderate. Boxwood is seen on the Pacific coast, north of San Francisco, but not to the south, where Cypress is popular. There is little Boxwood in the latitude of New York City, except for edgings, where for tall hedges Privet, Arbor-Vitæ, Hemlock, and Spruce are probably the most reliable evergreens. Arbor-Vitæ is unlikely to live longer than seventy years.
Although all of our States are not represented in this volume, these views are taken so generally from almost every section that the climatic conditions describing one State may usually stand as well at least for the States immediately adjoining. The only section of the Union omitted is that part through which run the Rocky Mountains. As a rule, this part of the country is not in its nature open to the cultivation of formal gardens, although its wild flora is remarkable enough to deserve special treatment.
In the brief chapters to follow there will be given more detail relating to climate, in order that we fellow gardeners in all parts of the Union may know something more about one another's garden program, our several problems, and our privileges in this outdoor life that we lead.