The proverb ‘great oaks from little acorns grow’ puts forward the idea that great enterprises may have modest beginnings.

It is intended to be an encouragement to persist with small efforts as they may build to grander ones in time – similar to the more modern ‘a journey of a thousand miles begins with a single step’.

‘Great oaks from little acorns grow’ was first used in that form around the start of the 19th century. Like many proverbs though the thought it contains had been expressed using different wording for many centuries before that.

The first use of the proverb in its precise present form that I know of is from Philadelphia newspaper The Examiner, September 1833:

‘Great oaks from little acorns grow,’ and I hope and trust that from your small beginning, this ancient and honorable Commonwealth will again renew her standing.