Poinsettia Pest Management 



ALAN T. EATON 

 UNH Cooperative Extension 



UNH Cooperative Extension ran a pilot poinset- 

 tia IPM program in 1993. Since we were trying 

 it out (and 1 was learning myselfl, we did not offer 

 the program to all interested growers. Instead, we 

 looked for experienced growers who were close to 

 the university, kept good records, and were inter- 

 ested. We decided on two locations. Newton Green- 

 houses included roughly 8000 square feet for poin- 

 settias and produced cuttings on the site. Pleasant 

 View Gardens devoted roughly 26,000 square feet to 

 poinsettias and brought in cuttings. From the time 

 of cutting arrival until December 1, the two sites 

 were visited weekly. We used sticky cards, examined 

 plants, and kept records of pesticide applications. 

 Extension workers performed the scouting and dis- 

 cussed the results and recommendations every week 

 with the managers. By the end of the season, it was 

 clear that NH poinsettia producers could benefit 

 from such a program. 



As this issue of The Plantsman goes to press, it is 

 unclear what the funding picture will be for fiscal 

 year 1995 (Oct. 1, 1994 to Sept. 30. 1995). If suffi- 

 cient funding is available. Extension will offer a full 

 IPM program for the 1994 crop, patterned after the 

 pilot program. If funds are tight, some alternate 



method of program delivery will be used, possibly 

 involving grower meetings, scouting demonstrations, 

 identification clinics and/or regular visits to inter- 

 ested managers. Irrespective of the funding situa- 

 tion, some kind of poinsettia IPM program will be of- 

 fered this coming season. 



Wfiflt follows is an overview of the important points in 

 management of whitefly problems that we learned as a result 

 of the pilot program. By following these steps, you may 

 be able to improve the way you handle whitefly 

 problems, and possibly save money at the same 

 time. Following the program, the growers with whom 

 we worked were able to produce crops that were al- 

 most entirely free of whiteflies at the time of sale. 

 Visits to several other greenhouses convinced us 

 that many New Hampshire growers are far from 

 achieving this. Whiteflies are the most serious of the 

 pest problems poinsettia growers face. Time does 

 not allow for the coverage of all pest problems in 

 this article (and still meet press deadline!), so 1 will 

 concentrate on this one. 



■ CLEAN STARTUP/KEEP IT CLEAN. This is the best 

 approach in dealing with whiteflies. It is particularly 

 true with poinsettias because 1) late cleanup of 



APRIL /MAY 1994 



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