Question: What are grafted tomatoes? I've seen them at my local nursery, and they cost about $18 per plant! Why are they so expensive? Are they better than regular tomatoes?

Answer: Grafted tomatoes usually are grown by grafting normal varieties of tomatoes onto rootstock of a super-strong, disease-resistant rootstock. Most of the time, heirloom varieties are grafted onto specially bred grafting rootstock, as heirlooms are normally susceptible to diseases and typically have low yields.

The rootstock is so robust that the plant grafted on to it grows really fast and big and produces higher yields. Grafting them to disease-resistant rootstock imparts disease resistance to them, too.

But there's a down side. Some say that the flavor is not as good on grafted heirloom tomatoes. Since the root stock is so robust, the heirlooms grow bigger, as they have more water. Water dilutes flavor.

The practice of grafting tomatoes came from the Old World and started being picked up here in the Pacific Northwest in the past decade or so, mainly by professionals who grow heirloom varieties in green or hoop houses. It allows growers to grow tomatoes, year after year, in the same soil without disease. Normally, soil will harbor fungal diseases from tomatoes, including Verticillium, late blight and Fusarium.

This winter, I visited Gathering Together Farm in Philomath to learn about grafting tomatoes. The 50-acre organic farm grafts thousands of heirloom tomato plants that eventually are planted out in hoop houses.

"We can't rotate our tomato crops year to year as we only have so much area on our farm that is suitable for tomatoes," explained farm co- manager Joelene Jebbia. "So grafting heirloom varieties works well for us,"

Jebbia and her crew start seeds for tomato grafting stock and the top heirloom tomato varieties in February. After the tomatoes have two sets of true leaves, they graft, usually in early March. The tomatoes heal and are planted out in hoop houses a few weeks later.

A clean environment for grafting is crucial. They use sterile, single-edge razorblades to cut off the top of each rootstock plant below the seed leaves (cotyledons). The heirloom plant to be grafted on the rootstock is cut off just below the cotyledons as well. They cut each plant's main stem at a 45 degree angle, press them together and put on a special silicon clip.

The plants are misted and put into a warm, (95 degrees) humid and dark "healing chamber" for a week. Then, slowly, over that week, the plants are exposed to a little more light each day — a half hour on day three after grafting, then an hour on day four and so forth.

Grafted plants do not develop a vascular connection for about a week, so it is important to keep the humidity high.

A friend and I tried all this, on our own, a couple of weeks ago. Within three days after grafting the heirloom varieties onto the rootstock we planted at the same time, all plants were dead.

I now understand why these grafted tomato plants are so expensive. It takes a lot of care, preparation and perseverance to get a successful plant. Even the pros lose a lot.

Want to try grafting tomatoes? It is too late for this year, but Territorial and Johnny's Seed are two companies that sell seed for grafting tomato rootstock plants. Don't be shocked. The seeds are quite expensive.

There are several how-to videos online. And the best publications I've found on how to graft come from Washington State University Extension:

Polk County Master Gardener Sale

If you weren't one of the lucky ones to get a grafted tomato — or regular tomato — from last weekend's Marion County Master Gardener Sale, about 50 grafted tomatoes will be available at the Polk County sale this weekend at the Polk County Fairgrounds, 520 S Pacific Highway W (99W) in Rickreall.

The sale, which will run 9 a.m. to 5 p.m. today and Saturday in building C, also will feature rare plants, more than 41 varieties of tomatoes, a variety of culinary herbs, squash, peppers and annuals, perennials, hanging baskets, trees, shrubs and grasses. Demonstrations throughout the sale will include soil blocks, raised beds, planting tomatoes, how to make garden tools out of used plastic containers, how to create a glass flower stake and discover how cooking with fresh herbs can enhance flavor. Check the Polk County Master Gardener Facebook page for demonstration times. For more information, go to

Growing Grafted Tomatoes

What: A representative from Ezra Organics will discuss the benefits of growing grafted (versus seed grown) tomatoes. Cultural information also will be provided to promote maximum growth and harvest

When: 2 p.m. Saturday

Where: Egan Gardens, 9805 River Road NE.

Cost: Free; registration requested

Information: (503) 393-2131, Ext.2,

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