Grafting Vegetables - Is it worth the trouble? Many growers say yes.

Amy Garrett, Small Farms Program, Oregon State University
Publish Date: 
Summer 2011
VolNo: 
Vol. VI No. 3

Jolene at GTF in hoop houses with grafted tomatoes. Photo provided by Amy GarrettGrafting vegetables has largely been limited to hydroponic systems in the U.S. although in recent years has become more popular in the field. Vegetable grafting is similar to grafting of fruits trees in the way that the rootstock is selected for vigor and disease-resistance, and the scion is selected for fruit quality and taste. The history of grafted vegetable production is rooted in Asia in the 1920’s. Today in Japan more than 90% of the watermelons, oriental melons, greenhouse cucumbers, tomato, and eggplant crops are grafted before being transplanted to the field or greenhouse.

Increasingly, grafted vegetables have received more attention as growers and researchers spread the word about the positive impacts including significant yield increase, disease resistance, and increased plant vigor. These benefits have already had a significant impact in sustainable agriculture.

Locally, Gathering Together Farm (GTF) in Philomath, Oregon started grafting their tomatoes several years ago. Based upon favorable results GTF has transitioned to most of their tomatoes being grafted. They have also begun to graft peppers, eggplant, and melons onto more vigorous, disease-resistant root stocks. Log House Plants in Cottage Grove, and Territorial Seed Company quickly sold out the majority of their grafted tomatoes marketed to home gardeners this year.

The main benefit of grafted vegetables is avoidance of soil-borne disease, especially in intensive vegetable growing operations where rotations may be difficult to implement. Grafting promotes increased plant vigor, and many growers see yield increases to 50% or more.

Grafted tomato. Photo provided by Log House Plants

Growers find great economic benefit in using grafted plants for high-value, low yielding crops like heirloom tomatoes. According to Jolene at GTF, one of the reasons they started grafting was “to actually make money on heirlooms”. Despite the huge expense of the root stock seed (as much as fifty cents per seed for tomato rootstock) growers find that the investment pays off. GTF over seeds the rootstock by 20 percent to account for uneven germination and the average 90 percent success rate. In addition to the cost of seed, there is the initial investment of setup, the labor-intensive act of grafting itself and the fact that you are putting all this effort into an annual. Andrew Mefferd with Johnny’s Selected Seeds says, “What’s harder: grafting tomato plants or tilling up 50 percent more ground?” That is one of the questions each grower must answer for him or herself.

Grafted tomatoes are planted out into the field two to four weeks later, but growers have found that they bear fruit much longer. The most popular rootstocks thus far have been Maxifort and Beaufort, which are available through Johnny’s Selected Seeds. A new rootstock called ‘Emperador’ has been released through Johnny’s. It is similar to Maxifort and Beaufort, and offers an option to growers that don’t want to buy from Monsanto-owned De Ruiter. This season, you still may be able to purchase grafted tomatoes from one of the suppliers listed below. For more detailed information on grafting tomatoes and other vegetables refer to the resources and links below.

Resources

  •  Grafting Tomatoes for Organic Open Field and High Tunnel Production Webinar In this webinar, David Francis of Ohio State University shared research findings and experience from an integrated organic program (IOP) project that has been addressing the use of grafting for organic systems. Find out more: www.extension.org/grafting-tomatoes