A Novel, Laborsaving Trellising System for Grape Tomatoes

A Novel, Laborsaving Trellising System for Grape Tomatoes

Summary

According to USDA statistics, the market demand for grape tomatoes is increasing significantly from year to year. This is a direct reflection of the consumer’s need for fresh and healthy snacks that are easy to store and process in the kitchen. On the positive for farmers, grape tomatoes are less prone to pathogens compared to other types of tomatoes and produce large quantities of fruit that have a long shelf life. On the negative side, the indeterminate growth habit of most grape tomatoes require high labor inputs for trellising and harvesting. Through a 2009 NESARE partnership grant, we were able to demonstrate that shaker-based harvest system for grape tomatoes could be feasible given a trellising system that could accommodate the collection portion of the system. Unfortunately, the most commonly trellising systems used in the field, Florida-weave and Wire cages, do not allow for shake based system. Also, shake-based systems waste vast quantities of fruit in the harvest of unripe tomatoes and require extensive sorting post harvest. Moreover, these systems require high levels of labor input an d it is challenging for growers to sterilize trellis components in order to minimize the transfer of soil-borne diseases to other fields. This project will test a novel grape tomato trellising system which will reduce labor and materials and utilize components that are readily sterilizable.

Objectives/Performance Targets

Evaluate a four stem, wire supported growing system for grape tomato production in a grower greenhouse. Modify the system as necessary before installing into other cooperator high tunnels and greenhouses.
The goal of this project as well as its’ predecessor is to take advantage of grape tomato plants’ heavy, indeterminate growth and create a trellis / harvest system that reduces labor while maintaining fruit quality and profitability. We will compare new trellis and training system designs with vertical “Florida weave-type” systems.

Systems will be evaluated on the ease of training tomato vines as well as the simplicity and cost of various trellis types. Creating a system that does not require ladders or scaffolding and at the same time causes the fruiting clusters to be easier to examine and harvest is the objective.

Accomplishments/Milestones

The trellis system as described in the proposal was installed at the Franklin County Horticulture Center High Tunnel as a ‘proof of concept’ prior to any attempt to install on grower / cooperator farms. While the desired ‘candy cane’ effect was created, the labor required as well as the actual cost of materials made this system unworkable. In addition, shaker harvesting continues to be impractical due to uneven ripening of grape tomato fruit. A simpler trellis based on ‘Florida weave’, but adding a curved bar at the top of the trellis for vines to flow over has the potential to be economically practical, easy for growers to manage and labor saving as all of the vines over 6′ will just lay on the Tenax mesh supported by the curved bars.

Since the all commercial varieties of grape tomatoes are indeterminate, there is little to no chance of using a harvester that shakes the vines. Too many unripe fruit are harvested along with ripe fruit. This reduces marketable yields and requires extensive sorting post harvest. It seems that the most practical system is to design the trellis and training system to make the fruit easy to examine, pick and sort in the field.

With so many new varieties of grape tomatoes coming to market, there is the potential that one that more evenly ripens fruit is in the pipeline. Therefore, evaluating grape tomato varieties for growth habit is another avenue worth consideration.

Impacts and Contributions/Outcomes

The search for systems that take advantage of the long vines created by grape tomato plants while at the same time making harvest more efficient and profitable has moved one step closer. The design as originally envisioned by Alex Surcica, original PI on this project simply created too much vine handling to be practical on a busy, diverse farm. However, the concept of created a crook or candy cane top that allows fruit to hang down for easy harvest bears examination and will be tested in 2012 field trials.

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