“What is the point of grafted tomatos? Great rootstock and tender tops with great tomatoes? I’m not seeing the point.”
The rootstocks used for grafting has strong resistance to most soil-borne diseases (fusarium and verticillium wilts, crown rot, etc.) and root-knot nematodes. Grafting allows you to grow varieties that are normally susceptible to those problems.
These rootstocks are hybrids of tomatoes and a wild tomato relative - if you grow out the rootstock it makes inedible or at least unpalatable fruit. These hybrids develop huge root systems which pump water and nutrients to the tops more efficiently than regular tomato roots. So they may cause extra-vigorous growth, better tolerance of heat and drought, and they *may* give better yields, mostly by making bigger fruits.
Grafting does not increase resistance to diseases that spread above ground (spread by wind or insects). Grafting doesn’t keep insects or critters from feeding on the plant, either. However, a big, healthy fast-growing plant may have a better chance of outgrowing foliage diseases and may recover better from damage.
If you’re pretty happy with your tomato crop already, grafted plants are probably not going to do much for you. But if you live in an area where soilborne diseases or nematodes make it tough to get a crop, they could help. Since nematodes are terrible where I live, I am experimenting with grafting my own (I bought rootstock seeds), and I will be planting others as controls. I am looking forward to the results of the experiment.
I know most of the pecan trees sold around here are papershells grafted onto native stock, and understand why. I was just unaware of grafted tomatoes.
I'll stick with my Romas for bulk production.
/johnny
If nothing else, it will be something to discuss over beers.
/johnny
I am looking forward to hearing how this all turns out. Keep us posted.