This is the first blog installment from Sean Brady, Supervisor of Sustainable Agriculture at Nourish the Planet. Today’s topic is disease control in a greenhouse environment.  As the weather here in Colorado has shifted from intense heat to wetter and cooler days we are seeing resurgence in some disease populations. The long heat wave we are experiencing has caused our plants to become stressed, in turn making them vulnerable to pests and disease that they would normally fight off on their own.

Our newest nuisance, powdery mildew, comes as a result of heavy afternoon rains causing increased humidity around the greenhouses.  Powdery Mildew is a fungus that attacks the succulent tissue of many plant species. Infected plants display white powdery spots on the leaves and stems with the characteristic powdery appearance.

When treating this problem in an aquaponics system, we need to be careful to choose a solution that will eliminate the problem without causing harm to our fish population. In this case we are using two different methods. First is our diluted milk spray, consisting of 1 part water to 9 parts milk. Our second is just a simple spray of hydrogen peroxide. Both of these solutions are applied by spray applicator to our crops with more focus on affected leaves and stems.

When spraying anything over your crops be sure to get it done before the sun is too high, water on the leaves can cause burning or worsen the mildew problem if it does not dry before the evening. Results should be seen with 1 – 2 weeks. We are already seeing improvement after just 4 days of application. Follow us on our website for more updates on pest and disease management!

Written by: Sean Brady, Co-Supervisor of Sustainable Agriculture Facilities