|
|
Griffin Greenhouse and Nursery Supplies, Inc.
Rick Yates, Technical Support Manager
ryates@griffinmail.com |
| |
| Greenhouses that are empty for even a day or two provide the opportunity to "clean house". Vigorous sanitation can not only reduce pest problems but can save you time and money over the long haul. Weeds serve as a reservoir to re-infect your crops with insects and diseases. Algae provide a breeding ground for fungus gnats and shore flies that plague greenhouses everywhere. Years of assisting growers with crop problems has convinced me that an ounce of prevention is indeed worth a pound of cure! |
| Weed control is a never ending project for many growers, but it is worth every bit of the effort. Even a few weeds left to limp along in a greenhouse shut down for the season is enough to harbor a supply of insects, mites, and certain diseases. Manually pulling the weeds is effective but time consuming. There are a few nonselective post-emergent herbicides that can be used in empty greenhouses: Envoy (grasses only), Finale, Round-Up Pro, Sycthe, and Touchdown Pro. Only Envoy, Finale and Scythe are labeled while there are plants present in the greenhouse. Whether you spray or pull the weeds, some weed seed will be left behind. Unfortunately, there is not a single pre-emergent herbicide labeled for use in greenhouses. Many cases of severe crop loss have been documented due to the use of pre-emergent herbicides in greenhouses. It is not worth the risk! Covering floors with ground cover fabric from Griffin can help you get the upper hand on weed control. |
|
|
| Algae are unsightly, unsafe on walkways, and a food source for exploding populations of fungus gnats and shore flies. Greenshield, Triathlon and ZeroTol can be sprayed on algae for quick control. Before you spray one of those products rake up plant debris, or use a "Shop Vac" on concrete floors. A new product from the makers of ZeroTol, GreenClean, is a granular product that cleans up algae and provides some residual control as well. Only ZeroTol can be used over the top of plants for algae control. |
| When treating floors, don't forget benches, baseboards, or any other hard surface that is hosting algae. Reducing the food source for fungus gnats and shoreflies makes control measures more effective. Clean holding tanks and other irrigation equipment between crops with Greenshield, Triathlon or ZeroTol. ZeroTol can also be used as continuous or pulse treatments in irrigation water for control of algae and many pathogens. |
| Standing water and poor drainage pose sanitation problems in the greenhouse. Shut down periods can be used to improve drainage and inspect plumbing to insure leaking fittings are not contributing to water problems. While you are down on your hands and knees, check for gaps or holes in your structure that provide easy entry for rodents and other trouble makers. "Down time" between crops is a great time to evaluate your ventilation and irrigation equipment. Griffin's Construction Department can help you determine if there are cost effective ways you can make sanitation easier through improving the environment in your greenhouse. |
|
|
|
Back to Technical Bulletins Archive
