Are all garden soils in New England acidic, with rocks?
No way! It's true that most of our soils are acidic, and our rocks are infamous; but there are pockets of alkaline soil, and chunks of clay, and sandy expanses with nary a rock in sight. If you're willing to take a chance with expensive (and/or beloved) acid-requiring plant material, then most of the time you'll be OK. However, it's safer to have the soil tested before you go ahead and plant.
WHAT IS NEW ENGLAND ANYWAY?
The classic view of New England, as learned by local schoolchildren, includes the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island and Connecticut. It rolls off the tongue like A,B,C,D,E ... The problem is that the Atlantic Ocean bounds New England to the east and Canada lies to the north, but there isn't a clear boundary to the west or south. Portions of eastern New York along the Hudson River kind of blend into Vermont, Massachusetts and Connecticut, and Long Island can be suspiciously like Cape Cod or the south coast of Massachusetts, Rhode Island and Connecticut. Open-minded New Englanders are inclined to accept New York as adjunct New England territory for some purposes, so long as the New Yorkers don't get too uppity about it.
A SHOCKINGLY BRIEF AND SUPERFICIAL GEOLOGY SUMMARY
A very long time ago, long before Spike started Garden Web, there were continents drifting and colliding, and volcanoes spouting lava, followed by glaciers grinding up the rocks, sliding and melting, and depositing stuff all over the land. A turbulent time.
The most recent ice age, the Wisconinan, started about 80,000 years ago and finished up about 14,000 years ago. Coming here, it scraped material off mountains and bedrock and carried with it whatever rocks were too hard to grind up. The softer rock got ground into smaller and smaller particles, ending up as what we now call gravel, sand, silt and clay. When the glacial lobes started melting and retreating, these rocks and particles dropped out and either stayed put or were redistributed by the melt-water rivers. The outwash plains and deltas contain large amounts of sand and gravel. Just look at the beaches on Cape Cod and the south coast of Massachusetts, Rhode Island and Connecticut.
Huge glacial lakes formed, with sediment at the bottom, and these glacial lakes were later emptied when temporary dams burst. The sediments often contain veins of clay and silt. Clay and silt deposits are found along the northeast coast and around Lake Champlain.
Smaller kettle ponds were formed when a big chunk of ice melted in place and slowly seeped away until the level reached the water table. These kettle ponds soon filled with organic material and many became bogs.
The temperature differential near the retreating ice sheet caused fierce winds to blow and deposit sand and silt every which way, and many upland soils in New England consequently are heavy in sand and silt.
As if this wasn't enough, the land gave a sigh of relief as the weight of...