Posts Tagged grafted vegetables

Seedling vs. Grafted Tomato: No Contest

Status of same varieties of seedling and grafted plants on the day the grafted ones arrived  on 4-25-13.

Status of same varieties of seedling and grafted plants on the day the grafted ones arrived on 4-25-13.

Talk about a one-sided fight, my plan to test the same varieties of grafted tomatoes against their seedling equivalents was a total bust. Why, you ask? Because when the grafted plants I ordered arrived last Thursday, this is what they looked like when I opened the box:

I've never had newly delivered plants look this bad -- including the ones I once ordered from Canada.

I’ve never had newly delivered plants look this bad — including the ones I once ordered from Canada.

If you click on the above photo to enlarge it, you’ll see that the plant on the right was broken when I opened the box. The leaves of the plant on the left — although they look a bit greener — are also wilted beyond recovery. Why? The soil in their little pots was Dust Bowl dry. No moisture at all.

This is one of those times when I let my enthusiasm for cutting-edge plants push me past careful reasoning. As I mentioned in my first post about this back in January, gardening magazines and catalogs have been full of buzz about the benefits of growing grafted vegetables. I didn’t really buy the hype, but I was curious, which is why I decided to try growing the same varieties of grafted and seedling tomatoes to see for myself.

But I didn’t research carefully. I impulsively ordered my grafted plants from the same company where I order my tomato and pepper seeds. Seeds from this company always give me near-100% germination and yield consistently healthy, productive plants, so I assumed they’d deliver similar quality in their grafted plants. What I didn’t know — because I didn’t ask — is that my tomato seed company does not produce the grafted tomatoes themselves. They buy them from a wholesale nursery that, I gather, has patented a line of grafted vegetables, which they produce and sell to retailers.

There’s nothing intrinsically wrong with this model, if all parties plan carefully to compensate for the travails of shipping tender summer vegetables across North America. However, if the plants I received are any indication, careful shipping was not part of the plan.

The company I order my tomato seeds from is in Wisconsin — an area where winter cold remains abundant. And from the insert with my grafted plants, I learned that the wholesale nursery that provided the grafted plants is in Oregon. Neither of these locations is, of course, near my location in North Carolina. And our growing seasons are not the same by a long shot. If I had thought about this more carefully, I would have realized that it was not likely that a company in Wisconsin could ship me healthy tomato plants in time for me to plant them out with the rest of my summer garden. In my defense, I did realize that the plants I received would probably be smaller than my seedlings, and I planned to account for that in my field trial. But I needed live plants to make that work.

As soon as I received my dying grafted tomato plants, I called the company that sold them to me. A very nice lady there asked me if the grafts were intact and the stems were still green. They were. She then instructed me to cut off all the dead/dying leaves, water and feed the plants in their pots, and put them in the sun. I confess I laughed out loud at these instructions.

“I’m sorry,” I said. “But I’ve been growing tomatoes for almost 50 years, and I’ve never seen a leafless tomato stem re-grow leaves, especially when its roots have been traveling long distances in bone-dry soil.”

“This is what we’ve been told to tell customers, ma’am,” she replied. “The grafted plants are so vigorous that they are supposed to recover very quickly.”

So I followed her instructions. I cut off all the dead/dying leaves, transplanted the sad little stubs to slightly larger pots, and drenched them thoroughly with the fish emulsion/seaweed mix that I administer to all my seedlings. The company had provided a packet of commercial, non-organic, very potent fertilizer (20-20-20) that I was supposed to mix with water and use, but this would have ruined my little test by not using the same fertilizer, and I’m an organic gardener. Also, I think throwing that potent a chemical fertilizer onto deeply stressed plants is more torture than first aid.

Here’s what the plants looked like when I removed them from their shipping box and placed them in my greenhouse:

The soil was completely dry.

The soil was completely dry.

Here’s what the plants looked like immediately after their surgery:

Post-surgery, before transplanting.

Post-surgery, before transplanting.

Here they are transplanted, watered, and fed after a few days in the greenhouse:

This is what they looked like four days later.

This is what they looked like four days later.

And this is what they looked like about two hours ago:

Increasingly brown and pitiful.

Increasingly brown and pitiful.

I think it highly unlikely that these sad brown stubs will sprout new leaves, but I’ll leave them in the greenhouse another week before I give them a decent burial in the compost pile.

I imagine the folks from whom I ordered my plants would offer to send me new plants if I asked, but there’s really no point now. My seed-grown plants are ready for transplanting as soon as our uncharacteristically chilly weather pattern finally breaks down next week.

If folks from the wholesale nursery or the tomato seed company want to respond to this post, I’ll be happy to publish their responses. I’ve made every effort to represent their processes accurately, but if I’ve erred in a supposition somewhere, I’ll be happy to correct it.

Bottom line: I let my enthusiasm for a new plant fad overpower my years of gardening experience. It would have been interesting to see how grafted plants perform, but my seed-grown plants provide all the produce I need every year anyway.

If I discover a local source for healthy grafted vegetables, I might try one some time just to satisfy my curiosity. But I am blessed with rich garden loam, a long growing season, and healthy seed-grown transplants. New-fangled grafted veggies can’t possibly compete with all that.

Seed-grown tomatoes are ready for transplanting as soon as our weather moderates.

Seed-grown tomatoes are ready for transplanting as soon as our weather moderates.






To graft or not to graft?

Do the advantages compensate for the extra cost?

Do the advantages compensate for the extra cost?

Actually, I’m not planning on grafting my vegetables myself. Spending time grafting annuals for a small home garden is not efficient for my situation. However, everywhere I turn — in catalogs and gardening magazines — the big buzz is about the advantages of planting grafted vegetables.  All the catalogs want to sell me these higher priced darlings.

If you use your favorite search engine to learn about the advantages of grafted veggies, you will get many, many results. A quick perusal on my part this morning was instructive. Apparently, the Japanese, especially greenhouse operations, have been grafting melons, squash, tomatoes, eggplants, and peppers for quite some time. Fruit production is supposed to be higher, as is the length of productivity — more fruits over a longer period.

For those unfamiliar with this ancient horticultural technique, grafting usually involves putting together two different cultivars of the same species. Fruit growers have been doing this for centuries. They look for a tree with a vigorous root system and less-than-spectacular fruits and a tree with great fruit quality but perhaps weaker roots. They take a cutting from the top of the tasty plant (called a scion) and plug it into the lopped-off top of the plant with vigorous roots (called the rootstock). When done correctly, the two pieces grow together nicely, leaving just a bit of a scar line where they join. The grafted fruit tree scion generally becomes able to produce more, healthier fruit, because it is growing on the vigorous rootstock.

Often, rootstock plants are more resistant to diseases than the tasty fruit plants, so when the rootstock is able to impart this advantage to its grafted top, fruit production improves. This propagation process makes perfect sense to me for long-lived perennials and trees. But for annuals in a home garden? I’m just not sure, which is why my 2013 garden will feature an experiment.

Tomato growers are hyping grafted heirloom plants as the solution to heirloom tomatoes’ notorious susceptibility to diseases, most of which linger in the soil for years. They claim that an heirloom tomato growing on disease-resistant rootstock will give growers much more vigorous plants, and prolonged crops of tasty Brandywines, Cherokee Purples, etc.

For some situations, this may be true. For example, if your garden space is so small that you can’t manage to rotate your crops each year, grafted veggies may help you. When you rotate crops, you avoid growing members of the same plant family in the same spot every year. I am blessed with a large garden area. I only grow the same plant family in the same spot after growing other plants there for the previous two years. This may not eliminate every vestige of lingering disease spores, but I think it helps a lot.

Squashes are members of the cucurbit family.

Squashes are members of the cucurbit family.

For those who may have forgotten, squash, melons, and cucumbers are all members of the cucurbit family. Tomatoes, peppers, eggplants, and potatoes are all members of the Solanaceae family, and peas and beans are legumes. Rotating where you grow these family groups makes it harder for their diseases and predators to lay in wait for them.

I have also read research that suggests that stressed plants produce more chemicals that make them less appealing to bad bugs and diseases. Grafting does stress plants, in that it requires them to allocate resources to heal the graft wound. Maybe this revs up the plant’s vigor?

The only way to learn more is to try some of these new-fangled plants, so I have ordered two grafted plants: a Brandywine and a Goliath. I have never had much success with seed-grown Brandywines in my garden. I usually get a few nice fruits, then the plant is overwhelmed by disease. I usually pull them out of the garden before the hybridized, disease-resistant tomatoes are halfway done. If the grafted Brandywine I plant this year really performs better, I will be a believer in the concept, although I’m still not sure it is enough of a return on investment to justify the cost.

The other grafted variety I’m trying is Goliath. This hybrid, disease-resistant tomato has always produced magnificently for me from seed-grown plants. I cannot imagine that grafting will improve its productivity in my garden, but it will be interesting to see.

Of course, I must have control plants to measure against the grafted ones, so I’ll also grow Brandywine and Goliath tomato plants from seed as usual. I’ll plant them at opposite ends of the trellises to minimize any cross contamination. May the best tomato win.

Fans of grafted tomatoes wax positively poetic about how disease-resistant rootstocks will prevent diseases from overwhelming tasty, disease-susceptible heirlooms. I am a doubter for my garden, because the root systems of all my tomatoes are always vigorous, and <knock on wood> I don’t have a nematode problem in my garden soil.

Most of the diseases that hit my tomatoes correlate with weather — hot humid summers breed fungal plagues — and insect infestations — spotted cucumber beetles, stink bugs, and other sucking insect predators insert diseases into plants when they suck out their juices. Unless the act of grafting in itself is the key to such improved vigor that even insect-introduced diseases are repelled, I doubt I’ll see much, if any, difference between my seed-grown controls and grafted test subjects.

Similarly, many of the soil-born wilts reach leaves when they are splashed up off the ground by watering or heavy rain. If you use organic mulch around your tomatoes, as I do, eventually soil-based fungi will find their way onto lower leaves, then work their way up from there. I don’t see how a disease-resistant rootstock will save a grafted heirloom in that scenario.

One more point for those who may have read about my tomato-planting technique in previous posts. I always dig a deep hole, maybe 8 inches below ground level, so that I can plant tomato seedlings deeply. The newly buried length of stem almost instantly begins to sprout roots, which may explain why my tomato plants always have vigorous, plentiful root systems.  However, for the grafted plants, I won’t be able to do this.

If I buried the grafted plants so that the graft line was below soil level, the buried stem of the scion (top part) would sprout roots. Because those roots would be from a plant that is less disease-resistant, any advantage conferred by the graft would be negated. This is another reason I’ll be surprised if the grafts win the productivity race. Their root systems will almost certainly remain smaller than their seed-grown competitors. If roots are the key piece of this puzzle, my money is on the seed-grown, deeply buried plants.

I’ll keep you posted as the season progresses. I’ve ordered all my seeds and plants, and I’ll be prepping my greenhouse soon for seed production mode. It will be most interesting to see the results of this experiment.

Have you ordered your seeds yet? If not, get busy. Seed sales are up as more folks are trying to grow some of their own food. To get the best selection, ordering soon is your best option.

Don't forget the herbs and flowers when you order your veggie seeds. A diverse garden is always healthier.

Don’t forget the herbs and flowers when you order your veggie seeds. A diverse garden is always healthier.

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