Dear Miss Floribunda,
My basement is full of maybe a gazillion tomato seedlings, doing well under fluorescent light. I guess I lost my head at your seed sale and overbought. I couldn’t wait to get them planted, and they sprouted almost immediately. Now I realize that I’d need an acre of land to include them all! My excuse is that there were just so many choices new to me that my curiosity got the best of me. The different varieties seem to have different assets, based on what I read on the seed packets. The new hybrids claim to resist diseases. The flavors of the old heirlooms are described almost poetically, but although the packets don’t say they are not resistant to disease, there’s usually nothing there to say that they are. I was wondering if I could try to graft the heirloom plants onto the disease-resistant ones, cutting down the number I have to find places for outside, and maybe combining the best traits of different types. Is this crazy? Do I sound like a mad scientist?
Future Frankenstein on Farragut Street
Dear Future Frankenstein,
You don’t sound like a mad scientist but an intelligent gardener following a time-honored agricultural practice. Grape-vine grafting is referred to on three-thousand-year-old Assyrian cuneiform tablets, and grafting of many kinds continues to be refined. However, like Dr. Frankenstein, you have to be sure you know what you’re doing. No, killer tomatoes won’t rise up and lay waste to Hyattsville, but your seedlings might not survive casual experimentation. Fortunately, on Saturday, March 10, Dr. Greengenes is going to give a workshop on grafting tomato seedlings and will demonstrate the best methods right before your eyes. You are encouraged to bring your seedlings and participate. Dr. Greengenes will have some throw-away seedlings for practice first. The workshop will take begin at 10:30 a.m. after a brief meeting of the Hyattsville Horticultural Society (HHS) at the home of Julie Wolf and Corey Twyman at 4008 Hamilton Street. Please call 301.461.6903 by Feb. 20 (at the very latest) to coordinate planting of seeds and to discuss any other concerns.
In the meantime, Dr. Greengenes has shared some general information with me. Our long summers and hot nights make tomatoes a favorite for the home garden in Hyattsville. However, after a few years, the lack of space in our gardens you have mentioned inevitably limits the number of times we can rotate our vegetables. After a while, such popular garden vegetables as cucumbers, melons, summer squashes and tomatoes become susceptible to soil-borne disease and pests. The varieties of vegetables that have the best disease resistance in their roots often yield very little or inedible produce. This is true with many tomato hybrids, and you will also find that some of the most charming heirlooms with the loveliest fruit and richest flavor are languorous at best. This is where grafting can make a big difference. It is routinely practiced commercially, where it is known to also greatly increase yield.
While already grafted tomato plants can be bought from suppliers, they are expensive, and you have already bought seeds and started seedlings. You don’t say which you selected, but of the hybrid varieties sold at the HHS seed sale, the most disease-resistant are Sweet 100s, Early Choice, Celebration and Best Boy. Although Dr. Greengenes will provide such tried-and-true rootstock as Estamino and DRO138TX onto which to graft your seedlings, you could experiment with what you have at home if you can’t attend the workshop. Your heirloom seedlings should have been planted at the same time and be at the same stage of development as your hybrids so that their stem diameters will match. Cut the stems of both at a 35-degree angle. Naturally, the rootstock stem should be slanted upward and the graftee stem downward. Secure the stems you have fit together with a silicone grafting clip. Grafting tape would be too cumbersome and might harm the delicate stems. You can remove a few leaves to reduce respiration. Place a small stick next to each newly combined plant for support, and cover each plant with a plastic bag to retain moisture. Put them in a warm, dark place for a week to heal. Dr. Greengenes will let you use her “healing ward” if you bring your seedlings to her workshop.
Although grafting is not considered difficult, you really would benefit from seeing it done by an expert, and using her reliable rootstock. Also, by coming to the workshop you will meet the organizers of Hyatt Park Community Garden. If you have more seedlings than you need, they would be happy to distribute them to other farmers, or perhaps arrange for you to obtain a plot. At any rate, you will meet other avid gardeners and be able to exchange information.