The idea of grafting plants is not a new one. In fact, the only way to reliably propagate strains of apple trees is to graft them. The seed of an apple is 'divergent,' meaning that each seed will tend to stray from the qualities exhibited by the parent plants. So, saving a seed from an apple and planting it is actually more likely to give you a scrubby little tree with tiny, tart apples than it is to replicate the tree it came from.
Recently, there has been more talk about grafting tomato plants. Which got me to thinking...dangerous pastime.
First, grafting is, in a nutshell, the process of taking the rootstock of one plant and affixing the scion (stem to leaf) to the rootstock. Rootstock is typically of a plant cultivar that is not necessarily desirable for the tomato it might produce. Instead, it is desirable because of its size, disease resistance, environmental requirements and/or plant vigor. The scion is the part that is desirable for the type of fruit produced by that cultivar. The theory is that you cut the top off of the rootstock and the bottom off of the scion and 'graft' them together. If you want more detail, you may find some here.
In general, it seems that this process appeals more to hydroponic and greenhouse tomato growers. Field growers, such as ourselves, are not likely to consider this option. Nonetheless, work is being done to test out viability for this (and other) processes. While I won't argue that research in food growing shouldn't occur. I have a hard time supporting the idea of grafting tomatoes....but why? (remember, these are my opinions!)
1. It's just another symptom of how we have all forgotten how to eat IN SEASON. The biggest reason for hydroponic and greenhouse production is to produce out of season. Therefore, grafting is an extension. In fact, too many people have no clue when most vegetables ARE in season. Even worse, there are numerous people who have no clue that potato tubers grow under ground, better tasting watermelons DO have seeds and wouldn't know a tomato plant from a carrot plant if they saw them.
2. This one takes a logic progression. First, if I'm growing a diverse crop in my field (which we do), with a good rotation plan (which we do), maintain good soil health (ditto) and good companions (which we do). And, if we do a good job starting these plants and hardening them off - not babying them so much that they can't handle the transfer to the great-wide world. Then, we tend to have vigorous, productive and healthy plants. What is the appeal to grafting in that case? It's just another way to increase the inputs/costs without adding much on the output side.
3. This is another way to continue to support monoculture crop production. The amount of time and resources required for grafting alone makes it likely that there will be a focus on this one crop. Any time you build up a monoculture, you increase the natural resistance to that monoculture. This creates a not-so-nice cycle that tends to result in a grower who MUST always graft, always use certain chemicals, etc etc. The inputs required to maintain production just keep going up. And, even if harvest levels are a tad higher, the net return begins to shrink.
4. It's all in the input vs output. Think about it. Grafting requires two plants to make one. Twice as much seed cost. Twice as much cost for all of the seed starting materials. It requires time to graft the plants. It requires some sort of plastic grafting clip to hold the plants in place. It requires a good location (typically greenhouse or some such sheltered location) to get the grafts to heal over. A person could argue that the disease and other problems in a certain location is so advanced that this is necessary to allow for even a reasonable crop. But, if it has gone that far - they should consider a different crop for a while!
Ok - maybe I am getting too preachy here. But, in my opinion, we need more small farms growing a diverse set of food crops to help feed local populations. The more complex we make agricultural food production seem, the less likely it is that we'll get more people to try it. In fact, the truth is that someone with very little capital - but alot of motivation and some smarts, can start a small farm. If you want to keep working smarter and better, it will eventually require capital - but you can build it up as you go.
We need MORE people willing to extend their own seasons with their own gardens AND their own canning/freezing. We need this more than we need more greenhouse production of tomatoes for out of season eating.
I really shouldn't think so much!