As the weather heats up in South Texas, the insect pests come alive in our gardens. This is the time of year when we gardeners go looking for the perfect pesticide to protect our plants.
Thomas Jefferson received a letter along these lines from his daughter, Martha. Martha Jefferson had grown up and gotten married, and she and her husband lived on a plantation not far from Jefferson’s farm at Monticello.
In her letter, Martha complained about the insect pests that were devastating her crops, and she hoped to get advice from her brilliant father. Jefferson’s reply is illuminating. He said, “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.”
Jefferson, one of the great farmers of American history, knew every trick in the book for fighting pests. But instead of prescribing an elixir for each insect attack, Jefferson advised her to apply a thick layer of fertilizer to her fields.
Jefferson’s advice is the cornerstone of organic agriculture. In fact, the working definition of organic gardening is to treat the soil, and allow the nutrients in the soil to take care of the plants. Healthy soil grows healthy plants, and strong plants resist disease and insect attacks. As Jefferson saw it, the best pesticide in the world is healthy, humus-rich, well-balanced soil.
On the other hand, unhealthy soil grows weak plants, and weak plants are bait for bad insects. Insect pests are designed by nature to seek out unhealthy plants and cull them from the gene pool. This is simply the law of natural selection at work in the garden.
All of nature conspires to destroy unhealthy plants, and disease and insects are the tools that nature uses to kill them. If the soil in your garden is weak, pest attacks are most likely just a symptom of the real problem.
Thomas Jefferson told us through his writings exactly how he grew such rich and vibrant soil. Next week, we will show how the animals on our farm in Rockport help us grow healthy soil for our crops–the same technique used by Thomas Jefferson in the gardens of Monticello.