ShareThisThe one thing I like most about gardening is its challenges. It can put the best horticulturists and other experts on a level playing field with even the newbies sometimes. Reflecting on years of challenges, Thomas Jefferson, a passionate gardener, said, "But though an old man, I am but a young gardener."
So with gardening, we don't have as much control as we'd like to think. If Mother Nature decides to throw us a curve, there's only so much we can do about it. Take the recent outbreak of late blight, a fungal disease that hit thousands of tomato seedlings across the Northeast recently. Late blight is characterized by dark spots or lesions on plant stems. And once a plant is infected, there's no way to save it.
Although some were quick to point an accusing finger at Bonnie Plants -- a large supplier of tomato plants -- as the source of the problem, it's hard to say where the disease originated. Airborne spores of late blight can travel several miles before landing on an appropriate host. Unseasonably cool temperatures and wet conditions can foster the spread of plant diseases such as late blight. With one of the wettest and coolest months on record for the Northeast, it's no surprise; conditions were prime for a potential outbreak. Even healthy plants from any source are sitting ducks to a disease that is quick to spread in open-air environments, such as garden centers.
But for any disease to exist and spread, three conditions need to be present: a virulent pathogen (one capable of causing a disease), a susceptible plant or "host" and the right environmental conditions for disease development.
What can you do?
Buying disease-resistant plants (not a guarantee against disease) and commercial fungicides or even homemade concoctions like milk or baking soda and water can help defend against disease. Although these products can be effective in reducing the chances of some infection, none can guarantee the total prevention of plant diseases when conditions are favorable.
1) Start with a healthy plant, free of any visible signs of spotting, yellowing, wilting or discolored roots.
2) Place your plant in the ideal environment for its preferred growing conditions. Vegetables and herbs prefer full sun. They also prefer adequate spacing to promote airflow. Less-than-ideal conditions result in stressed plants that are more susceptible to problems.
3) Spray plants with a multipurpose fungicide containing the active ingredient chlorothalonil, following the directions on the label. It's an effective control against most fungi, including late blight.
4) Avoid overhead watering when possible. Use soaker hoses, drip irrigation or a watering method that soaks the soil and roots, not the plant. Water on plants is a strong vector for disease pathogens.
5) Actively inspect plants. If you see any signs of disease, early detection is critical to prevent its spreading. At a minimum, remove the infected leaves. Do not add them to your compost where they can survive to spread again. Instead, place them in a plastic bag and throw them away or burn them.
For any plant disease, prevention, early detection and the removal and destruction of infected plants is the best overall approach to minimizing problems not only in your garden, but nearby gardens as well. These steps will help keep your garden growing strong even when Mother Nature throws you a curve.
(Joe Lamp'l, host of "GardenSMART" on PBS, is a Master Gardener and author. For more information, visit www.joegardener.com. For more stories, visit scrippsnews.com.)
THE GARDENER WITHIN
