2018 ASHS Annual Conference

Homeowners interested in the source of their food are continuing to drive the increased interest in home vegetable gardens. This is especially true in urban areas where small yards are the norm. Self-irrigated containers offer a successful gardening system for gardeners with limited space such as small yards, porches, or even balconies to grow vegetables. The goal of this project was to grow at three planting densities green and red romaine lettuce (Lactuca sativa var. longifolia) transplants commonly found by home gardeners at garden centers. The commercially available sub-irrigated EarthBox was used. Following the home owner instructions each EarthBox received pre-plant fertilizer (1 cup 10-10-10) and dolomitic lime (2 cups). Transplants grown in Jumbo 606 packs were planted on January 30, 2017 into peat-based container mix (Sunshine #8). Planting density treatments were 2, 4, or 8 transplants per sub-irrigated container. All plants were harvested on March 21, 2017. Data collected included weight of individual romaine lettuce heads and total weight per sub-irrigated container. Overall, the green romaine head weights were greater than the red. The total head weights for the green romaine produced greater weights per sub-irrigated container regardless of planting density. Planting density total head weights regardless of lettuce type were similar for the 4 and 8 transplant treatments and greater compared to the 2 transplant treatment. When comparing the green and red romaine lettuce there was no difference in the two head treatment, but individual green heads were greater than the red in the four and eight head density treatments. This information is valuable for the home gardener with limited growing to determine how much romaine lettuce to grow to meet family needs.