Seasonal Greenhouses Open Mid April till July 1 Since our first greenhouse in 1986, we have developed into a five large house operation. Pam’s Greenhouses offer a lovely selection of plants from delightful annuals, plentiful perennials, alluring trees, ideal shrubs, and breathtaking roses. Quality and service is very important to us also. We always want to offer our customers the very best in selection but also quality. We want our products to look good and maintain the quality that we are proud of.