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Cultivating high quality plants without aesthetic injury is no easy feat for ornamental nursery growers. Ultimately, being well prepared and making informed decisions pays off for pest and disease management.
Apply the Integrated Pest Management (IPM) Concept.Integrated means combining a variety of pest management techniques and concepts that can either prevent pest introduction, eradicate pests, or reduce pest populations to lessen economic impact while maintaining plant quality. Some key preventative practices that should be put in place include sanitation. Properly cleaning up the production area of crop debris and unsaleable plants, along with adequate control of weeds is critical. Unsightly (equals unhealthy) plants and weeds are often sources for pests and pathogens. Use new or properly disinfected tools and materials to reduce contamination and spread of pests and diseases. Cultural practices such as maintaining plant health through adequate nutrition and providing quality fertilizer in a timely manner can reduce plant stress and minimize potential for disease. Practices such as the use of microjet or drip irrigation to keep water below the plant canopy can significantly reduce spread and infection by foliar pathogens that cause leaf spots and blights. When using overhead irrigation, try to time watering events to minimize periods of leaf wetness. For example, water in the morning to allow the plant canopy to dry out in the sun during the day. Scouting or monitoring is one of the most important principles of IPM and is critical for success. The timely detection of pests and accurate assessment of population densities are important for IPM decision making. Early detection of pests enables the nursery to reduce plant damage, improve plant quality, reduce production costs, avoid production delays, and increase profits.
Use readily available resources to choose the best solutions. Identify resources before questions arise. There are important contacts such as university extension faculty, county extension agents, horticulture consultants, company technical representatives and diagnostic labs available for consultation. Pesticides are an essential tool for pest and disease management but need to be used appropriately to perform at their best. First and foremost, always refer to and follow the manufacturer’s label before applying. Consider the application method. Regardless of the application method, it is critical that the product is applied where needed, which is dependent on the formulation and behavior of the active ingredient. Understanding how a product works, will help determine the most appropriate application method. Systemic vs Non-systemic products. Non-systemic products need to contact the intended plant tissue (i.e., the underside of leaves) to be effective and provide protection. Some products provide translaminar protection, which means the treatment moves throughout the leaf to protect both the upper and lower leaf surface where many pests and pathogens are hiding. Systemic products are most often applied as drench or sprench applications, contacting the roots for uptake and subsequent movement upward in the xylem into above ground portions of the plant. Growers who account for how these products work will have greater success on managing plants pests and diseases. At the end of the day, it’s best to apply pesticides preventatively to adequately control plant pests, diseases and weeds before they occur. Be sure to account for the time of sale, so that the plants have lasting protection during transportation or while sitting on shelves at the retail store. Growers will be able to rest easy knowing consumers will bring home beautiful and healthy plants.

2 The REI for Altus in California is 12 hours.
3 Hachi-Hachi SC is also a fungicide and will add in the control of powdery and downy mildew. Other products to consider as a tank mix or rotation include Sevin® SL (1A), TriStar® 8.5 SL (4A), Xxpire® (4c+5) Distance® (7C), Rycar® (9B), Ventigra ® (9D), Akari® (21A), Mainspring® (28) Pradia™ (28 + 29) and Aria® (29)

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