Rotating veggies in garden plot?

I've heard it's good idea to rotate your veggies each year within a garden plot. How long does one need to wait before replanting tomatoes and other cucurbits in the same spot--not to mention other veggies?
I had Early Blight in my tomatoes this year and ended up pulling them all up. Do I need to wait several more years before replanting those beds with tomatoes?
TIA

I've recently done a lot of reading on rotation and the miniumun is every other year, good is every 3-4 years, best is a 5+ year rotation. There is also a specific order of rotation. One of many links with good information http://www.yankeegardener.com/resource/croprotate.html The rotation helps with both diseases and pests.

Thank you, MSRobin, for this most informative website. I suspected that a good long rotation would be best. I appreciate your input.

My pleasure! I was having a difficult time trying to figure it all out when I first started reading about it, but finally got it. Might as well check out companian planting, too. That's the next step. LOL!

A bit more info hopefully without confusing you:
Vegies belong to " families" . Within the family they use the same nutrients and attract the same pest, so your plants will be less and less healthy if you don't move them around.
Also legumes ( peas/beans) actually adds nitrogen to the soil so if your clever you take advantage by putting a high nitrogen feeder in after legumes. That's the general idea anyway.
I just try not to put things that look the same in the same place year after year; the flower is a good indicator of which family it belongs to.
Potato family: potatoes, tomatoes, chilli, egg plant, capsicum (peppers)
Melons/ pumpkin/ squash ( corn being a heavy feeder goes here too)
Legumes; beans and peas ( put with ..... cabbages)
Cabbage family ( brassicas): cauliflower, broccoli,
Also treat root vegies: carrot, turnip, swede, radish as a vague family. i hope that helps get you started.
www.no-dig-vegetablegarden.com/crop-rotation.htmlc. This link may help too.

If I've confused you I'm sorry! ;)

Thanks, Marianne. You have helped a lot. I think I finally "get" the idea of the different families of veggies and why they need rotation, preferably every four to six years. For a beginner like me, it can hardly be too specific. Msrobin's link also gave some very specific recommendations of exactly which veggie to plant where.
So I've decided that my formerly large tomato patch is going to have several beds of different veggies next summer, but no potato-family ones for four years. (I'll try containers and grow-bags for these.) I'll just move the beds in a clockwise rotation year to year.
Thanks so much for the help. These "beginner forums" are terrific.

Hello CapeCod Gardener, when rotating crops, do take into consideration plants' mature height. Orient your plants in the beds to avoid tall plants blocking the sun from the shorter plants.

Good reminder, Luv2work. That's so true. Methinks that a garden plan drawn up with the orientation of the sun is called for.
I am such a novice. Experienced gardeners probably just know all this by instinct.
Thanks for the reminder.

no, we just have a few more years of mistakes behind us !!
I wouldn't give up on the tomatoes in the ground though, maybe just add some compost/ manure to refresh the soil and plan where you'll put them next year.

thanks everyone for the good info here. You are good teachers.