How would you like to be on the cutting edge in your garden this year? You will get your chance by going to the WSU/Spokane County Master Gardener Plant Sale and Garden Fair on Saturday, where they will be selling organic grafted tomato plants for the first time.
So what’s the big deal about grafted veggies?
You might recall that I grew two Black Pear tomato plants last summer. One was grafted, the other wasn’t. The grafted plant grew vigorously thanks to its huge root system. It produced nearly three times the tomatoes the non-grafted plant did and I became a believer.
A few of my Master Gardener colleagues also grew grafted tomatoes last year and they all agree these plants are incredibly productive.
Grafting vegetable plants is relatively new to the U.S. gardening scene, but the technique has been used in Asia since the 1920s. They’ve been grafting different varieties of veggies onto rootstock that has increased disease resistance and is more tolerant of cooler soil conditions. It is estimated that Asian countries produce nearly 1 trillion grafted tomato, pepper, eggplant, cucumber, melon and squash plants annually.
The grafting method is labor-intensive. Growers first plant seeds of a vegetable variety they’re interested in grafting and seeds for the rootstock. This must be carefully timed so both plants are at the same stage of development. Then it gets even more challenging.
Grafting a cutting, or scion, onto a rootstock involves a painstaking process in which growers must precisely match the cambium layers from the rootstock to those of the scion. This work is most commonly done by hand. Although grafting robots have been introduced recently, the growers I spoke with prefer the accuracy of their human workers.
In the case of grafted tomato plants, their roots’ ability to gather more moisture and nutrients in the soil, and their increased resistance to soil-borne pathogens and nematodes, is responsible for phenomenal growth. The result is larger yields of tomatoes.
Which brings us back to Saturday’s Plant Sale and Garden Fair. The Master Gardeners will be selling the following grafted tomato varieties for $10 each: Early Girl, Big Zac, Momotaro, Siberian Galina, Brandywine Yellow, Siberia [this variety is different from the Siberian Galina variety], Beefsteak Nepal and Russian Rose.
While $10 might seem pricey for a tomato plant, consider that one grafted plant has the potential to produce three or more times the tomatoes a non-grafted plant would while taking up much less space in your garden.
When it comes to growing grafted vegetable plants, there is one important rule to follow at planting time:
The graft must be planted above the soil surface or roots will develop from the scion, which overrides the benefits of the rootstock it has been grafted onto. If you look at the lower stem of the plant, the graft is a thicker area where a horizontal or diagonal line will be visible. That’s the area you need to keep above the soil at all times. Avoid pulling on the plant’s stem when transplanting it since that could damage the graft.
Once planted, the seedlings will take about two weeks to become established. Be sure to give them fertilizer that will provide more potassium than nitrogen, such as blood meal. Then stand back and watch the plant work its magic.