CONTENTS THE BUSINESS MAGAZINE FOR COMMERCIAL GROWERS DECEMBER 2019 | VOLUME 29, NUMBER 12 On the Cover Very few flowers inspire as much excitement and interest as dahlias. Turn to page 36 to learn about 30 FEATURES 20 Plant Health New Biopesticides for Greenhouse Crops Are you seeking biological controls to protect your plants? These four new products are worth trying out. By A. R. Chase 24 Management Tackling Transportation Efficiency Going into 2020, how can growers address logistical challenges affecting their businesses? By Lauren Snyder 28 Plant Health Using a PGR to Rescue Plants from a PGR How can a proven PGR kick start plants and save crops from overapplication? By Dudley Dabbs 30 Hot Tropics Let's Talk Tropical Foliage Vines From houseplant to the garden, alocasia and colocasia varieties bring a tropical touch to any application. By Andrew Britten 34 Culture Report Verbena Vanessa Series Big, bold, season-long color is made easier with this top-performing verbena. By Mike Fernandez 4 DECEMBER 2019 GPNMAG.COM 36 COLUMNS 14 Perspectives Is That for Fun or Is That Your Job? By Cheni Filios 16 Duets Managing Product Assortment Shrink: New Genetics vs. Time-Tested Varieties By Peter Konjoian and Will Healy 36 Vaughn's View Dazzling Dahlias By Vaughn Fletcher 42 Technically Speaking How Much Supplemental Lighting Do You Need? By Erik Runkle Miss our November issue? It's now available to view on gpnmag.com DEPARTMENTS 6 Editor's Report 8 Industry News 10 Calendar 12 Chat Room 32 New Products 40 Variety Spotlight 41 Classifieds/Ad Index 34 'Labella Maggiore Rose Bicolor' and other top trial performers. (Photo: Beekenkamp)http://www.gpnmag.com http://www.GPNMAG.COM