Quality of Hybrid and Heirloom Tomatoes Grown for the Early Market Using Season Extension Structures

High tunnels allow for earlier crop harvests in temperate climates with the added benefit of increasing crop quality. In 2009 and 2010, 3 hybrid (‘BHN 589’, ‘Fletcher’ and ‘Primo Red’) and 3 heirloom (‘Arkansas Traveler’, ‘Cherokee Purple’ and ‘Valencia’) tomato varieties were grown in high tunnels and in outdoor plots across three planting dates (late March, mid-April and early May). All plots were managed organically in both years. On each plant, the third fruit cluster from the bottom was tagged and fruit were harvested when fully ripe. To assess quality, we measured skin color, firmness, soluble sugars, titratable acidity and phytonutrient content (β-Carotene, lycopene and lutein). Skin color was influenced by variety, but not planting date or production system.  All hybrid varieties were firmer than heirloom varieties, and all high tunnel tomatoes had higher levels of soluble sugars than those grown in the open field. Tomato acidity differed by variety, with ‘BHN 589’ being the most acidic. In 2009, phytonutrient differences were observed; ‘Valencia’, which produces orange fruit, had the highest amount of β-Carotene compared to other varieties and no lycopene. Lycopene content was greater in high tunnel plots compared to open field plots, and this was affected by variety. ‘Cherokee Purple’ had higher levels of lycopene than the other varieties. Additionally, fruit from the March planting date had higher levels of lycopene. Lutein content was also influenced by variety, with ‘Cherokee Purple’ having the highest levels. Inversely, fruit from the May planting date had higher levels of lutein. The use of high tunnels may not only result in earlier production, but increase flavor components and phytonutrients in tomato fruit as well.