wrote:

Hi, Everybody,

I have read that tomatoes should be placed in a different area
each year, due to the risk of diseases building up in one spot of
soil.

Apparantly, this also applies to potatoes. Are they
interchangeable (meaning that I shouldn't put tomatoes in the
spot where last years potatoes were)?

Absolutely. Don't put tomatoes where potatoes were grown last year and
vice versa.



So I am wondering how many different areas are needed? Meaning,
How many seasons/years does a previously used spot need, before
it is safe to put tomatoes there again?

If I rotated around three areas, would that be enough? Or four?


Four would be ideal. There are all kinds of websites and books out there
that describe the proper four crop rotation techniques.

You can start he http://www.thevegetablepatch.com/

Just click on the How To Guides and choose Crop Rotation. That'll give
you the basics. I agree with his advice on potatoes. Keep them separate
altogether. I do that by planting them in containers with new potting
soil every year. The used soil goes onto the lawn in the fall.
Apparently, old potato soil is welcomed in the lawn. (Don't try the tire
technique he mentioned - the spuds only rot in the tires. You can do the
same thing by building a raised bed from wood or cinder blocks).


Is there anything else that shouldn't go in last season's tomato
area?


Peppers definitely. There may be more.


..

Zone 5a in Canada's Far East.