Thomas Jefferson’s Soil

December 01, 2010 | 1:12 pm

We needed a vacation, time away from the hustle and bustle of our busy lives. This time it was to Virginia to visit family. Scheduled into every great McKenna vacation is a trip to a garden, park, greenhouse or arboretum. This time it was Thomas Jefferson’s Monticello.

I have read many of Jefferson’s garden quotes; it was my time to see firsthand the inspiration of those quotes. Approaching Monticello is gorgeous, trees full of color and life!  I was most interested in the garden, although his home is as equally interesting.

Jefferson’s vegetable garden is a 1,000 foot-long terrace carved into the mountain. You can imagine my delight in seeing such a historic garden. Jefferson grew 330 varieties of vegetables and herbs and 170 varieties of fruit in the eight-acre fruit garden. That is some serious gardening.

My first observation of the garden was the red clay-type soil.  Fascinating to know the third president and I have a common garden frustration, clay soil! Jefferson was an advocate for improving soil health. He regularly added compost, including manure and composted leaves, to his garden. He was a witness to how the organic matter increased drainage and promoted greater fertility.

The garden was his living laboratory. He wrote, “The failure of one thing is repaired by the success of another.” Reassuring to know that Jefferson and I both killed a few plants. He collected seeds and cuttings from all over the world. He is accredited for introducing a wide range of vegetables, herbs, fruits and perennials to America.

In Peter Hatch’s book, “The Gardens of Thomas Jefferson’s Monticello” he writes of Jefferson’s philosophy. Here is an excerpt.

Jefferson’s essential philosophy of gardening was perhaps best summarized in a letter to his daughter Martha after she complained of insect-riddled plants in the Monticello vegetable garden: “We will try this winter to cover our garden with a heavy coating of manure. When earth is rich it bids defiance to droughts, yields in abundance, and of the best quality. I suspect that the insects which have harassed you have been encouraged by the feebleness of your plants; and that has been produced by the lean state of the soil. We will attack them another year with joint efforts.”

Jefferson understood the success of his garden was a direct relation to the health of the soil. I continued to be fascinated with Jefferson’s garden enthusiasm. I read a portion of “Thomas Jefferson’s Farm Book.” In it, I discovered that in 1816, Jefferson began adding plaister to the soil. Plaister is calcined gypsum, also known as plaster of Paris. It provides two macro-nutrients to the soil, sulfur and calcium. Jefferson wrote to Richard Peters in June of 1816, “We are indebted to you for much of our knowledge as to the use of the plaister, which has become a principal article of our improvements, no soil profiting more from it than that of the country around this place.”

Today, gypsum is still utilized by gardeners and farmers to improve soil fertility and drainage.

Reflecting back on our tour of Monticello, I walked away with a new appreciation for Jefferson’s wisdom, work ethic and patriotism. I had known Thomas Jefferson as the third President of the United States and the principal author of the Declaration of Independence and now I know him as a fellow gardener.

To learn more about Monticello, visit the web site at