High Tunnel Tomatoes

Greenhouse tomato production is on the rise among New York's family farms. However, heating a greenhouse in upstate New York requires high-energy input and can be cost prohibitive. An alternative to a fully heated greenhouse is the hoop house or high tunnel. Unlike greenhouses, these structures have no supplemental heat or automated ventilation. High tunnels can be moved, which offers an advantage for rotating into fresh soil for tomato culture, to avoid pest and disease build-up, as well as nutrient depletion.

Little research had been done on growing tomatoes in high tunnels in New York, so a local produce grower, Howard Hoover and I agreed to conduct a variety trial at Howard's farm in Penn Yan. We submitted our proposal to Northeast Sustainable Agriculture Research and Education (SARE), and received approval. Our goals:

· Compare 4 tomato varieties in an unheated high tunnel by measuring yield in total weight, total number of fruit, and mean fruit weight.

· Observe disease and insect pest trends in the high tunnel, and manage them in a sustainable manner.

Our results were exciting. We found that indeterminate varieties that had previously only been grown in heated greenhouses would perform well in an unheated high tunnel. The indeterminate varieties yielded more consistently over time than the determinate variety in our trial. This may be an advantage or disadvantage depending on market windows. If a grower prefers a heavy flush of fruit prior to availability of field grown tomatoes, the determinate variety may be preferable. Alternatively if the grower desires a long, sustained harvest, the indeterminate types may be superior.

In our trial two indeterminate varieties, Big Beef and Boa, yielded significantly higher than the common determinant variety for high tunnels, Mtn. Spring, in both mean weight per plant and mean fruit per plant. Big Beef yielded significantly heavier fruit than the three other varieties. These results suggest that high tunnel tomato growers could realize higher yields by adopting indeterminate varieties and culture common to heated greenhouses.

Table 1. Mean yield per plant, mean fruit per plant and mean fruit weight of 4 tomato varieties in a grower's high tunnel.

     Variety            Mean yield per plant (pounds)           Mean fruit per plant           Mean weight per fruit (pounds)
     Big Beef              21.23 a*                                              37.38 a b                               0.57 a
     Boa                    19.41 a                                                 40.86 a                                   0.47 b
     Trust                   16.49 b                                                34.54 b c                                0.47 b
     Mtn. Spring         16.35 b                                                33.12 c                                   0.50 b
     LSD (P<0.05)     2.12                                                     4.24                                       0.03

*Means with different letters (grouping) differ significantly according to Fishers Protected LSD (P<0.05).

We endeavor to design a low-input, sustainable approach to off-season tomato production and the high tunnel may decrease pesticide inputs. For example, no pesticides were used in this trial. Minor levels of foliar diseases occurred in the high tunnel, but none approached an economic threshold. An interesting development was widespread late blight (Phytophthora infestans) in field grown tomatoes throughout the region. The disease was present in the farm's home garden 30 feet from the high tunnel, yet no late blight was observed within the tunnel. This can be credited to the warm, dry environment inside the tunnel.

That warm environment is also great for working together with family. When it is raining outside and fieldwork has to be put on hold, children and parents can get together in the hoop house to pull weeds, trellis, prune and harvest.

Our high tunnel tomato trial was a success, not only because our data showed clear differences between varieties, but also because we were able to share this information with other greenhouse tomato growers throughout the Finger Lakes. A high tunnel twilight meeting was convened in early August. Over 40 growers observed our treatments and yields. We even had tomato tastings! We hope to continue our efforts in the coming growing season. Thanks to NE SARE for supporting this project.