crop rotation

[Granny]

It says in this months KG that tomatoes and potatoes should be treated as a group for crop rotation. I thought you were supposed to keep them apart to try and stop blight transferring from one to the other. Any views on this?
------------
Granny

[Allan]

Magazines aren't infallible. I prefer your idea.

[alan refail]

When I grew in an area fairly free of blight (W Yorkshire)I didn't worry how close potatoes and tomatoes were. Now I grow in an area where blight is guaranteed (NW Wales) I don't grow tomatoes outside at all. In any case, if blight is pretty much guaranteed here, I don't think it transfers from one to the other, rather affects both at the same time. I try to do my best by planting and harvesting potatoes as early as weather permits.

[Alison]

I expect it is just that both toms and pots are solanums, so they take the same sort of nutrients out of the soil, plus are susceptible to the same types of pests and diseases (e.g. blight). If they are in the same rotation group, they will not follow on each other in the same patch. If tomatoes went in the patch of land where potatoes had been the previous year, not only might their essential nutrients be depleted, but there might be a build-up of their pests and diseases waiting in the soil.
Alison.

[mazmezroz]

I have always believed that toms and pots should be separated cosof the blight risk. I never grow them anywhere near eachother....